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Zhang, Yan. "The impact of midbrain cauterize size on auditory and visual responses' distribution." unrestricted, 2009. http://etd.gsu.edu/theses/available/etd-04202009-145923/.
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Thesis (M.S.)--Georgia State University, 2009.<br>Title from file title page. Yu-Sheng Hsu, committee chair; Xu Zhang, Sarah. L. Pallas, committee members. Description based on contents viewed June 12, 2009. Includes bibliographical references (p. 37). Appendix A: SAS code: p. 38-53.
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Horttana, Jonas. "Real Estate Forecasting – An evaluation of forecasts." Thesis, KTH, Fastigheter och byggande, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-124002.
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This degree project aims to explore the subject of forecasting, which is an ongoing and much alive debate within economics and finance. Within the forecasting field the available research is vast and even if restricted to real estate, which is the main focus of this paper, the available material is comprehensive. A large fraction of published research concerning the subject of real estate forecasting consists of post mortem studies, with econometric models trying to replicate historical trends with the help of available micro and macro data. This branch within the field of forecasting seems to advance and progress with help of refined econometric models. This paper, on the other hand, rather examines the fundamentals behind forecasting and why forecasting can be a difficult task in general. This is shown with an examination of the accuracy of 160 unique forecasts within the field of real estate. To evaluate the accuracy and predictability from different perspectives we state three main null hypotheses: 1. Correct forecasts and the direction of the predictions are independent variables. 2. Correct forecasts and the examined consultants are independent variables. 3. Correct forecasts and the examined cities are independent variables. 4 The observed frequencies for Hypothesis 1 indicate that upward predictions seem to be easier to predict than downward predictions. This is however not supported by the statistical tests. The observed frequencies for Hypothesis 2 clearly indicate that one consultant is a superior forecaster than compared to the other consultants. The statistical tests confirm this. The observed frequencies for Hypothesis 3 indicate no signs of dependence for the variables. The statistical tests confirm this.<br>Detta examensarbete ämnar att utforska ämnesområdet kring prognoser och prognosmakande, vilket är en högst levande debatt inom ekonomi och finans. Inom detta område är tillgänglig forskning mycket omfattande och även om materialet begränsas till fastighetsmarknaden, som är huvudspåret i denna uppsats, är mängden information ansenlig. En stor andel av publicerad forskning som berör prognoser av fastighetsmarkanden består ofta av studier av typen "post mortem", där man med ekonometriska modeller försöker efterlikna tidigare historiska trender med hjälp av tillgänglig mikro- eller makrodata. Denna gren av forskningen tycks vinna mark och fortsätter att utvecklas med hjälp av allt mer avancerade ekonometriska modeller. Denna studie fokuserar däremot snarare på de fundamentala elementen av prognosmakande och varför detta ibland kan vara en problematisk uppgift. Detta visas med hjälp av en undersökning gällande utfallet och träffsäkerheten av 160 unika prognoser på fastighetsmarknaden. 7 För att utvärdera träffsäkerheten hos prognoserna sätts tre olika nollhypoteser upp: 1. Korrekt prognos och riktning av prognos är oberoende variabler. 2. Korrekt prognos och konsult är oberoende variabler. 3. Korrekt prognos och undersökta städer är oberoende variabler. De observerade frekvenserna för Hypotes 1 indikerar att uppåtgående prognoser är enklare att förutspå än övriga prognoser. Detta kan dock inte stödjas av de statistiska testerna. De observerade frekvenserna för Hypotes 2 indikerar tydligt att en konsult är en överlägsen prognosmakare än övriga konsulter. Detta stöds av de statistiska testerna. De observerade frekvenserna för Hypotes 3 indikerar inget samband av beroende mellan variablerna. Detta kan dock inte stödjas av de statistiska testerna.
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De, Champlain André F. "Assessing test dimensionality using two approximate chi-square statistics." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7848.
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Roberts, Georgia Ruth Carleton University Dissertation Psychology. "Contributions to chi-squared tests with survey data." Ottawa, 1985.
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Alves, Ricardo Cavalcanti. "Análise empírica sobre a gestão e a avaliação de marcas em empresas brasileiras." Universidade Presbiteriana Mackenzie, 2012. http://tede.mackenzie.br/jspui/handle/tede/894.
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Previous issue date: 2012-03-26<br>Fundo Mackenzie de Pesquisa<br>In the last decades the world has seen great dissemination of powerful brands, local and world-known, not infrequently assessed in billions of dollars, leading to massive sales of
products and services associated with them. And in that context it is clear the impact of the intrinsic value of the intangible assets brand of companies in mergers and acquisitions.Nowadays, it has been clear that a Company valuation has a relevant amount related to intangible assets and, among these, brands have significant importance. This study aimed to investigate what is the general perception, the control method and the valuation of brands on companies operating in Brazil, by gathering information about the companies where students and recent graduates of post-graduate in business administration related courses used to work.Thus, from the sample group of 134 companies operating in Brazil, were extracted details of five dimensions of brand: awareness about its importance, financial valuation of the brand,accounting recognition of brand value, management of this intangible asset and its use as a tactical and strategic performance ratio. The methodology used was a survey that, from statistical tests Chi-square Pearson test led to the conclusion that there is no significant relationship between the fact that companies sell products and services and aspects relating to each of the five dimensions studied. Other variables statistically compared by using the chisquare
test meant for the sample companies, among other findings, the significant correlation between large companies and the fact that companies evaluate brands or negotiate them. Also,
the study took into account the criteria of attitude scores of respondents based on the Likert scale. The resulting data reveal that the brands are still in need of greater attention from companies. It is a minority in the sample studied the incidence of financial valuation of the brand, as well as the proper focus on accounting and management reports. Internal control over brand management and variable compensation system based on ratios of the brand,though present, such items were observed in low intensity in the sample companies.<br>Nas últimas décadas o mundo tem assistido à grande proliferação de marcas poderosas, local e mundialmente conhecidas, avaliadas não raramente em bilhões de dólares, levando a vendas em massa de produtos e serviços a elas associadas. E nesse contexto é notório o impacto do
valor intrínseco do ativo intangível marca no valor das empresas em movimentos de fusões e aquisições. Hoje sabe-se que um valuation conta com parte relevante de seu montante relacionado a ativos intangíveis e, entre tais, as marcas possuem significativo destaque. Este trabalho objetivou investigar qual é a percepção geral, o método de controle e a avaliação das marcas em companhias em operação no Brasil, a partir de levantamento de informações sobre as empresas em que trabalhavam estudantes e recém egressos de cursos de pós-graduação profissional em áreas ligadas à administração de negócios. Assim, da amostra pesquisada de 134 companhias atuantes no país, foram extraídos detalhes de cinco dimensões da marca:percepção sobre sua importância, avaliação financeira, reconhecimento contábil de seu valor,gestão desse ativo intangível e de seu uso como indicador de performance tática e estratégica.
A metodologia utilizada foi um levantamento (ou survey) que, a partir de testes estatísticos qui-quadrado de Pearson , permitiu a constatação de que não há relacionamento significativo entre o fato das empresas comercializarem produtos e serviços e aspectos ligados a cada uma
das cinco dimensões estudadas. Outras variáveis comparadas estatisticamente pelo teste de qui-quadrado resultaram para as companhias da amostra, entre outras constatações, a
significativa correlação entre as empresas de grande porte e o fato das empresas avaliarem marcas ou as negociarem. O estudo também levou em conta o critério de escores de atitudes dos respondentes baseado na escala Likert. Os dados resultantes revelam que as marcas carecem ainda de maior atenção por parte das empresas. É minoritária na amostra estudada a incidência de avaliação financeira da marca, assim como o devido enfoque em relatórios
contábeis e gerenciais. Os controles internos de gestão da marca e o sistema de remuneração variável baseado em indicadores da marca, embora existam, mostraram-se itens pouco observados nas companhias da amostra.
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Cheng, Kai-ho. "The Chi-square test when the expected frequencies are less than 5." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39558708.
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鄭啟豪 and Kai-ho Cheng. "The Chi-square test when the expected frequencies are less than 5." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39558708.
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Saaidia, Noureddine. "Sur les familles des lois de fonction de hasard unimodale : applications en fiabilité et analyse de survie." Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR14794/document.
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En fiabilité et en analyse de survie, les distributions qui ont une fonction de hasard unimodale ne sont pas nombreuses, qu'on peut citer: Gaussienne inverse ,log-normale, log-logistique, de Birnbaum-Saunders, de Weibull exponentielle et de Weibullgénéralisée. Dans cette thèse, nous développons les tests modifiés du Chi-deux pour ces distributions tout en comparant la distribution Gaussienne inverse avec les autres. Ensuite nousconstruisons le modèle AFT basé sur la distribution Gaussienne inverse et les systèmes redondants basés sur les distributions de fonction de hasard unimodale<br>In reliability and survival analysis, distributions that have a unimodalor $\cap-$shape hazard rate function are not too many, they include: the inverse Gaussian,log-normal, log-logistic, Birnbaum-Saunders, exponential Weibull and power generalized Weibulldistributions. In this thesis, we develop the modified Chi-squared tests for these distributions,and we give a comparative study between the inverse Gaussian distribution and the otherdistributions, then we realize simulations. We also construct the AFT model based on the inverseGaussian distribution and redundant systems based on distributions having a unimodal hazard ratefunction
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Pang, Xiao L. "Assessing the performance of the approximate chi-square and Stout's T statistics with different test structures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0010/NQ52277.pdf.
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Mullen, Jerry D. (Jerry Davis). "A Comparison of Some Continuity Corrections for the Chi-Squared Test in 3 x 3, 3 x 4, and 3 x 5 Tables." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc331001/.
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This study was designed to determine whether chis-quared based tests for independence give reliable estimates (as compared to the exact values provided by Fisher's exact probabilities test) of the probability of a relationship between the variables in 3 X 3, 3 X 4 , and 3 X 5 contingency tables when the sample size is 10, 20, or 30. In addition to the classical (uncorrected) chi-squared test, four methods for continuity correction were compared to Fisher's exact probabilities test. The four methods were Yates' correction, two corrections attributed to Cochran, and Mantel's correction. The study was modeled after a similar comparison conducted on 2 X 2 contingency tables and published by Michael Haber.
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Stasiukaitytė, Irma. "Infarkto gydymo įvairiais vaistais statistiniai tyrimo metodai." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2004. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2004~D_20040610_174400-77084.
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The goal of the present thesis is to ascertain the impact of different drugs, intended for the infarction treatment; investigation of the other factors, which may stipulate bleeding in the course of the operation and within the post-operation period. The investigation was carried out in two stages. During the first stage the data was accumulated for processing (investigation of the sample homogeneity and normality); the second stage implied solution of the statistical tasks (solution of the tasks, which correspond to the goals of the thesis). The methods of data analysis and the models of binary logistic and linear logistic regression were applied. 89 patients, who survived the myocarditis infarction, were investigated and it was ascertained that there is no huge difference in between the tranexamic acid and aprotinin. The bleeding complications may be caused by aspirin, which has been used before the operation. One of the complications, i.e. the drainage, may be predicted, judging from the amount of haemoglobin, haematocrit in the blood as well as creatinin. The model of the binary logistic regression assisted us in drawing the conclusion that smoking, hypothermia, euroscore and other factors produce an impact upon the bleeding complications.
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Steele, Michael C., and n/a. "The Power of Categorical Goodness-Of-Fit Statistics." Griffith University. Australian School of Environmental Studies, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20031006.143823.
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The relative power of goodness-of-fit test statistics has long been debated in the literature. Chi-Square type test statistics to determine 'fit' for categorical data are still dominant in the goodness-of-fit arena. Empirical Distribution Function type goodness-of-fit test statistics are known to be relatively more powerful than Chi-Square type test statistics for restricted types of null and alternative distributions. In many practical applications researchers who use a standard Chi-Square type goodness-of-fit test statistic ignore the rank of ordinal classes. This thesis reviews literature in the goodness-of-fit field, with major emphasis on categorical goodness-of-fit tests. The continued use of an asymptotic distribution to approximate the exact distribution of categorical goodness-of-fit test statistics is discouraged. It is unlikely that an asymptotic distribution will produce a more accurate estimation of the exact distribution of a goodness-of-fit test statistic than a Monte Carlo approximation with a large number of simulations. Due to their relatively higher powers for restricted types of null and alternative distributions, several authors recommend the use of Empirical Distribution Function test statistics over nominal goodness-of-fit test statistics such as Pearson's Chi-Square. In-depth power studies confirm the views of other authors that categorical Empirical Distribution Function type test statistics do not have higher power for some common null and alternative distributions. Because of this, it is not sensible to make a conclusive recommendation to always use an Empirical Distribution Function type test statistic instead of a nominal goodness-of-fit test statistic. Traditionally the recommendation to determine 'fit' for multivariate categorical data is to treat categories as nominal, an approach which precludes any gain in power which may accrue from a ranking, should one or more variables be ordinal. The presence of multiple criteria through multivariate data may result in partially ordered categories, some of which have equal ranking. This thesis proposes a modification to the currently available Kolmogorov-Smirnov test statistics for ordinal and nominal categorical data to account for situations of partially ordered categories. The new test statistic, called the Combined Kolmogorov-Smirnov, is relatively more powerful than Pearson's Chi-Square and the nominal Kolmogorov-Smirnov test statistic for some null and alternative distributions. A recommendation is made to use the new test statistic with higher power in situations where some benefit can be achieved by incorporating an Empirical Distribution Function approach, but the data lack a complete natural ordering of categories. The new and established categorical goodness-of-fit test statistics are demonstrated in the analysis of categorical data with brief applications as diverse as familiarity of defence programs, the number of recruits produced by the Merlin bird, a demographic problem, and DNA profiling of genotypes. The results from these applications confirm the recommendations associated with specific goodness-of-fit test statistics throughout this thesis.
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Caprio, Joseph M., Harold C. Fritts, Richard L. Holmes, David M. Meko, and Deborah L. Hemming. "A Chi-Square Test for the Association and Timing of Tree Ring-Daily Weather Relationships: A New Technique for Dendroclimatology." Tree-Ring Society, 2003. http://hdl.handle.net/10150/262549.
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This study introduces a new analytical procedure based on the chi-square (x²) statistic to evaluate tree- ring weather relationships. An iterative x² method, developed previously for relating annual crop production to daily values of meteorological measurements, is applied to tree-ring data and compared to results obtained from correlation and bootstrapped response function analyses. All three analytical procedures use a southern Arizona chronology (Pinus arizonica Engelm.) and the latter two use monthly average meteorological data. The x² analysis revealed most of the relationships exhibited by the correlation and response function analyses as well as new linear and nonlinear associations. In addition, cardinal values were obtained that define daily thresholds of the meteorological variables at which the limitation to growth becomes significant. Some of the associations are plausible from the physical system but require more study to confirm or refute a real cause and effect. A few associations appear to be too late in the season or too early in the previous year to affect ring width. We recommend that this x² technique be added to the existing dendroclimatic procedures because it reveals many more possible cause and effect relationships.
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Wu, Baohua. "Data Driven Approaches to Testing Homogeneity of Intraclass Correlation Coefficients." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/math_theses/92.
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The test of homogeneity for intraclass correlation coefficients has been one of the active topics in statistical research. Several chi-square tests have been proposed to test the homogeneity of intraclass correlations in the past few decades. The big concern for them is that these methods are seriously biased when sample sizes are not large. In this thesis, data driven approaches are proposed to testing the homogeneity of intraclass correlation coefficients of several populations. Through simulation study, data driven methods have been proved to be less biased and accurate than some commonly used chi-square tests.
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Gayle, Suelen S. "A simulation study of the size and power of Cochran’s Q versus the standard Chi-square test for testing the equality of correlated proportions." Kansas State University, 2010. http://hdl.handle.net/2097/3881.
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Master of Science<br>Department of Statistics<br>Paul I. Nelson<br>The standard Chi-square test for the equality of proportions of positive responses to c
specified binary questions is valid when the observed responses arise from independent random
samples of units. When the responses to all c questions are recorded on the same unit, a situation
called correlated proportions, the assumptions under which this test is derived are no longer
valid. Under the additional assumption of compound symmetry, the Cochran-Q test is a valid
test for the equality of proportions of positive responses. The purpose of this report is to use
simulation to examine and compare the performance of the Cochran-Q test and the standard Chisquare
test when testing for the equality of correlated proportions. It is found that the Cochran-Q
test is superior to the Chi-square test in terms of size and power, especially when the common
correlation among the binary responses is large.
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Li, Rong. "A Tree-based Framework for Difference Summarization." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1334277940.
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ERIC, AIDOO, and ZHENG SAIJING. "HAPPINESS INDEXTHE CONSTRUCTION AND ANALYSIS." Thesis, Högskolan Dalarna, Statistik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:du-4853.
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This study aims to investigate the important indicators that contribute to happiness among Beijing residence. The residents of Beijing were taken as the target population for the survey. A questionnaire was used as the main statistical instrument to collect the data from the residents in Beijing. In so doing the investigation employs Factor analyses and chi-square analyses as the main statistical tools used for the analyses in this research. The study found that Beijing residents gained greater happiness in the family, interpersonal relationships, and health status. The analysis also shows that generally, the residence of Beijing feels happier and also in terms of gender basis, females in Beijing feel happier as compare to their male counterpart. It will find that gender, age and education are statistically significant when dealing with happiness.
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Tran, Vuong, and Sebastian Öhgren. "Analys av kvalitet i en webbpanel : Studie av webbpanelsmedlemmarna och deras svarsmönster." Thesis, Linköpings universitet, Statistik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-95456.
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During 2012, the employer of this essay carried out a telephone survey with 18000 participants and a web panel survey with 708 participants. Those who partook in the telephone survey were given a choice to join the web panel. The purpose of this work is to study the participants of the telephone survey and see if they reflect the Swedish population with regards to several socio-demographic factors. Also, we intend to investigate if the propensity to join the web panel differs for participants of the telephone survey with regards to various socio-demographic affiliations. It is also of interest to study if the response pattern is different for participants of the telephone survey that would like to join the web panel and those who reject. A comparison of response pattern between the telephone survey and web panel survey has also been done, to see if there exist any differences for these two groups of surveys. The statistical methods used in this essay are descriptive statistics, multiple logistic regression and decision trees. Conclusions to be drawn with result from these methods are that the participants from the telephone survey do reflect the Swedish population regarding certain socio-demographic factors and that there is a slight difference in propensity to join the web panel for people which have dissimilar socio-demographic affiliation. It has also been found that there is a slight difference in response pattern for participants who would or would not like to join the web panel, as well as differences in response pattern also exist between the telephone survey and the web panel survey.
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Huang, Hesha, Mengwei Jiang, and Fan Liu. "Water Pollution in China : study on the relationship between economic development and water pollution." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-10861.
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Purpose/aim The purpose of the research is to analyze the relationship between water pollution (WP) and the economic development in China. We found a vicious cycle that at the same time as China’s economy has developed; the WP has become the focus of attention, and has also caused huge economic losses. Faced with this situation, this topic is really worth to study. Design/methodology/approach The research adopted a quantitative methodology for the exploration, and conducted a survey through questionnaires which were answered by different people. These respondents come from four areas in China. After having conducted the survey, we selected three typical provinces as representative for each area, and surveyed the basic information about these places. The sample information was calculated by the Chi-square test. The results will be analyzed together with the findings below. Findings The findings indicated that through an analysis of GDP, population, the economic development level and the degree of WP, there is relationship between economic development and WP. When people ignore the problem of WP, and just focus on the economy, the relationship shows that the more developing of economy, the more serious the WP becomes. Originality/value The original idea in our dissertation is to discuss the relationship between economic development and WP in China. The water problem and economic development form a vicious circle. And it seriously affects the whole China. The study has a value for the improvement of the environmental awareness of all the people in China, and advocates the government to develop the economy, and at the same time protect the water sources.
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Tao, Jinxin. "Comparison Between Confidence Intervals of Multiple Linear Regression Model with or without Constraints." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-theses/404.
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Regression analysis is one of the most applied statistical techniques. The sta- tistical inference of a linear regression model with a monotone constraint had been discussed in early analysis. A natural question arises when it comes to the difference between the cases of with and without the constraint. Although the comparison be- tween confidence intervals of linear regression models with and without restriction for one predictor variable had been considered, this discussion for multiple regres- sion is required. In this thesis, I discuss the comparison of the confidence intervals between a multiple linear regression model with and without constraints.
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Monaco, Linda Gokey. "A Comparison of Three Methods of Detecting Test Item Bias." Thesis, North Texas State University, 1985. https://digital.library.unt.edu/ark:/67531/metadc331416/.
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This study compared three methods of detecting test item bias, the chi-square approach, the transformed item difficulties approach, and the Linn-Harnish three-parameter item response approach which is the only Item Response Theory (IRT) method that can be utilized with minority samples relatively small in size. The items on two tests which measured writing and reading skills were examined for evidence of sex and ethnic bias. Eight sets of samples, four from each test, were randomly selected from the population (N=7287) of sixth, seventh, and eighth grade students enrolled in a large, urban school district in the southwestern United States. Each set of samples, male/female, White/Hispanic, White/Black, and White/White, contained 800 examinees in the majority group and 200 in the minority group. In an attempt to control differences in ability that may have existed between the various population groups, examinees with scores greater or less than two standard deviations from their group's mean were eliminated. Ethnic samples contained equal numbers of each sex. The White/White sets of samples were utilized to provide baseline bias estimates because the tests could not logically be biased against these groups. Bias indices were then calculated for each set of samples with each of the three methods. Findings of this study indicate that the percent agreement between the Linn-Harnish IRT method and the chisquare and transformed difficulties methods is similar to that found in previous studies comparing the latter approaches with other IRT methods requiring large minority samples. Therefore, it appears that the Linn-Harnish IRT approach can be used in lieu of other more restrictive IRT methods. Ethnic bias appears to exist in the two tests as measured by the large mean bias indices for the White/Hispanic and White/Black samples. Little sex bias was found as evidenced by the low mean bias indices of the male/ female samples and the fact that the male/female mean bias indices were lower than those of the White/White in 33% of the samples.
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Gayle, Suelen S. "A simulation study of the size and power of Cochran's Q versus the standard Chi-square test for testing the equality of correlated proportions." Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3881.
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Chen, Xinyu. "Inference in Constrained Linear Regression." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-theses/405.
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Regression analyses constitutes an important part of the statistical inference and has great applications in many areas. In some applications, we strongly believe that the regression function changes monotonically with some or all of the predictor variables in a region of interest. Deriving analyses under such constraints will be an enormous task. In this work, the restricted prediction interval for the mean of the regression function is constructed when two predictors are present. I use a modified likelihood ratio test (LRT) to construct prediction intervals.
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Beirowski, Karin. "Cultural influences on attitudes toward aggression : a comparison between Spanish, Japanese and South African students." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53341.
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Thesis (MA)--University of Stellenbosch, 2003.<br>ENGLISH ABSTRACT: The primary aim of the present study was to examine whether the culture of a society influences
the way in which people justify certain aggressive behaviours in certain situations. A total of 756
students from Spain, Japan and South Africa participated in completing the CAMA, a measure of
justification of aggression. The results showed that there were significant differences within the
countries. There were differences in the levels of acceptance of certain acts between these
countries. Further fmdings also indicated that there was a difference between the males of the
countries and between the females of these countries. It was found that cultural influences and
the norms within these countries bring about differences in justification of aggression in different
situations. There were also some general trends of acceptance, with direct and indirect verbal
acts e.g. sarcasm, hindering and shouting being more acceptable than physical acts such as
hitting, killing and torture. It is hoped that the present findings of this research will make
members of society more aware of their responsibility to help reduce aggressive acts by teaching
and reinforcing norms against it. It is also hoped that the international community will gain better
insight into the fact that South-Africa faces unique challenges because of the political and social
changes in the country.<br>AFRIKAANSE OPSOMMING: Die primêre doel van die huidige studie was om vas te stelof 'n samelewing se kultuur 'n rol
speel by die regverdiging van sekere aggressiewe gedrag in bepaalde omstandighede. 'n Totaal
van 756 studente van Spanje, Japan en Suid Afrika het die CAMA vraelys voltooi. Die vraelys
meet die regverdiging van aggressie in sekere omstandighede. Betekenisvolle verskille is tussen
die lande gevind. Daar is ook betekenisvolle verskille tussen die mans van die drie lande asook
tussen die vrouens van die drie lande gevind. Daar is gevind dat kulturele verskille en die norme
binne 'n samelewing meebring dat daar verskille is in die mate waarin samelewings sekere
aggressiewe gedrag aanvaarbaar vind in sekere situasies. Daar was ook 'n groter algemene
aanvaarbaarheid van verbale aggressie bv. sarkasme, verhindering en skreeu as fisiese aggressie
soos slaan, om dood te maak en marteling. Hopelik maak hierdie navorsing mense meer bewus
van elkeen in die samelewing se verantwoordelikheid om die norme teen geweld te versterk
asook om die norme aan hulle nageslagte oor te dra. Verder sal die internasionale gemeenskap
hopelik beter insig kry oor die unieke uitdagings wat Suid-Afrika bied as gevolg van die
politieke en sosiale veranderinge in die land.
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Yan, Lu. "Risk Management Project." Digital WPI, 2012. https://digitalcommons.wpi.edu/etd-theses/648.
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In order to evaluate and manage portfolio risk, we separated this project into three sections. In the first section we constructed a portfolio with 15 different stocks and six options with different strategies. The portfolio was implemented in Interactive Brokers and rebalanced weekly through five holding periods. In the second section we modeled the loss distribution of the whole portfolio with normal and student-t distributions, we computed the Value-at-Risk and expected shortfall in detail for the portfolio loss in each holding week, and then we evaluated differences between the normal and student-t distributions. In the third section we applied the ARMA(1,1)-GARCH(1,1) model to simulate our assets and compared the polynomial tails with Gaussian and t-distribution innovations.
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Shen, Chen. "Risk Management Project." Digital WPI, 2012. https://digitalcommons.wpi.edu/etd-theses/650.
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In order to evaluate and manage portfolio risk, we separated this project into three sections. In the first section we constructed a portfolio with 15 different stocks and six options with different strategies. The portfolio was implemented in Interactive Brokers and rebalanced weekly through five holding periods. In the second section we modeled the loss distribution of the whole portfolio with normal and student-t distributions, we computed the Value-at-Risk and expected shortfall in detail for the portfolio loss in each holding week, and then we evaluated differences between the normal and student-t distributions. In the third section we applied the ARMA(1,1)-GARCH(1,1) model to simulate our assets and compared the polynomial tails with Gaussian and t-distribution innovations.
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Sacks, William Andrew. "Healthcare providers' experience of chronic grief in a pediatric subacute facility." CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/2034.
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The purpose of this study was: (1) to evaluate the level of grief experienced by healthcare providers in a pediatric subacute facility, (2) to compare the levels of grief between different groups of healthcare providers (Certified Nurses' Aides, Licensed Nurses, and Respiratory Care Practitioners), and (3) to describe the personality/demographic factors that influence a healthcare provider's ability to cope effectively with compound grief.
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Boulet, John R. "A Monte Carlo comparison of the Type I error rates of the likelihood ratio chi-square test statistic and Hotelling's two-sample T2 on testing the differences between group means." Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5708.
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The present paper demonstrates how Structural Equation Modelling (SEM) can be used to formulate a test of the difference in means between groups on a number of dependent variables. A Monte Carlo study compared the Type I error rates of the Likelihood Ratio (LR) Chi-square ($\chi\sp2$) statistic (SEM test criterion) and Hotelling's two-sample T$\sp2$ statistic (MANOVA test criterion) in detecting differences in means between two independent samples. Seventy-two conditions pertaining to average sample size ((n$\sb1$ + n$\sb2$)/2), extent of inequality of sample sizes (n$\sb1$:n$\sb2$), number of variables (p), and degree of inequality of variance-covariance matrices ($\Sigma\sb1$:$\Sigma\sb2$) were modelled. Empirical sampling distributions of the LR $\chi\sp2$ statistic and Hotelling's T$\sp2$ statistic consisted fo 2000 samples drawn from multivariate normal parent populations. The actual proportion of values that exceeded the nominal levels are presented. The results indicated that, in terms of maintaining Type I error rates that were close to the nominal levels, the LR $\chi\sp2$ statistic and Hotelling's T$\sp2$ statistic were comparable when $\Sigma\sb1$ = $\Sigma\sb2$ and (n$\sb1$ + n$\sb2$)/2:p was relatively large (i.e., 30:1). However, when $\Sigma\sb1$ = $\Sigma\sb2$ and (n$\sb1$ + n$\sb2$)/2:p was small (i.e., 10:1) Hotelling's T$\sp2$ statistic was preferred. When $\Sigma\sb{1} \not=\Sigma\sb2$ the LR $\chi\sp2$ statistic provided more appropriate Type I error rates under all of the simulated conditions. The results are related to earlier findings, and implications for the appropriate use of the SEM method of testing for group mean differences are noted.
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Lynch, O'Neil. "Mixture distributions with application to microarray data analysis." Scholar Commons, 2009. http://scholarcommons.usf.edu/etd/2075.
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The main goal in analyzing microarray data is to determine the genes that are differentially expressed across two types of tissue samples or samples obtained under two experimental conditions. In this dissertation we proposed two methods to determine differentially expressed genes. For the penalized normal mixture model (PMMM) to determine genes that are differentially expressed, we penalized both the variance and the mixing proportion parameters simultaneously. The variance parameter was penalized so that the log-likelihood will be bounded, while the mixing proportion parameter was penalized so that its estimates are not on the boundary of its parametric space. The null distribution of the likelihood ratio test statistic (LRTS) was simulated so that we could perform a hypothesis test for the number of components of the penalized normal mixture model. In addition to simulating the null distribution of the LRTS for the penalized normal mixture model, we showed that the maximum likelihood estimates were asymptotically normal, which is a first step that is necessary to prove the asymptotic null distribution of the LRTS. This result is a significant contribution to field of normal mixture model.
The modified p-value approach for detecting differentially expressed genes was also discussed in this dissertation. The modified p-value approach was implemented so that a hypothesis test for the number of components can be conducted by using the modified likelihood ratio test. In the modified p-value approach we penalized the mixing proportion so that the estimates of the mixing proportion are not on the boundary of its parametric space. The null distribution of the (LRTS) was simulated so that the number of components of the uniform beta mixture model can be determined. Finally, for both modified methods, the penalized normal mixture model and the modified p-value approach were applied to simulated and real data.
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Röjdén, Thyberg Sandra, and Mélica Gabrielsson. "ASI-Intervjun : en explorativ studie av samband och grupperingar." Thesis, Linköpings universitet, Statistik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69740.
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Med en explorativ ansats syftar denna studie till att kartlägga samband och jämföra grupperingar bland klienter som fått genomföra en ASI-intervju hos Kriminalvården. Studien bygger på 2 317 intervjuer med fokus på missbruksproblematik, gjorda under perioden 2008-2010. Vi illustrerar grafiskt intressanta samband och tittar även på hur klienternas hjälpbehov varierar inom olika livsområden. Ytterligare en aspekt av studien är att utvärdera datamaterialets kvalitet samt att studera eventuellt bortfall för de olika variablerna. Materialet är av relativt god kvalitet och förekomst av respondenters vägran är inte tillräckligt omfattande för att påverka analyser och slutsatser. De felaktigheter som kunde konstateras härhör nästan uteslutande från tillvägagångssätt vid inmatning av data i systemet. Eftersom flertalet av variablerna är kvalitativa visade sig lämpliga analysmetoder vara chi-två-test, korrespondensanalys samt associationsanalys. Den stora majoriteten av våra resultat bekräftar den bild flera tidigare studier ger av gruppen missbrukare och få oväntade samband kunde konstateras. En majoritet av klienterna är män (85%) och den genomsnittliga åldern är 34 år. Intervjuarskattningar av klienternas hjälpbehov visar att narkotika och kriminalitet utgör de absolut största problemen. Dominerande drog är amfetamin (18%), följd av alkohol (15%) och cannabis (10%). Vi kan konstatera att ett flertal signifikanta skillnader föreligger mellan män och kvinnor samt mellan olika åldersgrupper. Unga klienter uppvisar överlag större problem med kriminalitet, narkotika, arbete/försörjning och psykisk hälsa. Med ökande ålder följer istället svårigheter med fysisk hälsa och alkohol. Män uppger vanligen att de har större problem med kriminalitet och narkotika, medan kvinnor ofta redovisar ett större hjälpbehov inom områdena familj/umgänge, fysisk hälsa och psykisk hälsa.<br>With an explorative approach, this master thesis attempts to map associations and compare groupings of clients who have undergone an ASI Interview by The Swedish Prison and Probation Service, Kriminalvården. The study is based on 2 317 interviews carried out during the period 2008-2010, focusing on abuse of alcohol and narcotic substances. We will graphically illustrate interesting associations and study how the need for help varies throughout different areas of the respondents’ lives. Another aspect of this study is to evaluate the quality of the data material and to investigate non-response in the different variables. The quality of the material is fairly high and non-response is not extensive enough to affect analysis and inference. The errors found are almost exclusively due to how data is fed into the system. Since the majority of variables are qualitative, appropriate methods of analysis proved to be chi-square tests, correspondence analysis and association analysis. Most results confirm the existing image of an abusive personality, which has been presented in several studies before this one. A majority of the clients are men (85%) and the average age is 34 years. Interviewer estimates of the respondents’ need for help show that narcotic substances and criminal behavior are by far the greatest problem areas. The predominant drug is amphetamine (18%), followed by alcohol (15%) and cannabis (10%). We have established several significant differences between men and women, and between clients of different age groups. Young respondents show greater problems concerning criminal behavior, narcotic substances, work/providing and psychological health. With increased age we see enhanced difficulties regarding physical health and alcohol. Men more often exhibit problems concerning criminal behavior and narcotic substances, while women need increased help in areas of family/social life, physical health and psychological health.
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Belen, Rahime. "Detecting Disguised Missing Data." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610411/index.pdf.
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In some applications, explicit codes are provided for missing data such as NA (not available) however many applications do not provide such explicit codes and valid or invalid data codes are recorded as legitimate data values. Such missing values are known as disguised missing data. Disguised missing data may affect the quality of data analysis negatively, for example the results of discovered association rules in KDD-Cup-98 data sets have clearly shown the need of applying data quality management prior to analysis. In this thesis, to tackle the problem of disguised missing data, we analyzed embedded unbiased sample heuristic (EUSH), demonstrated the methods drawbacks and proposed a new methodology based on Chi Square Two Sample Test. The proposed method does not require any domain background knowledge and compares favorably with EUSH.
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Price, Emily A. "Item Discrimination, Model-Data Fit, and Type I Error Rates in DIF Detection using Lord's χ2, the Likelihood Ratio Test, and the Mantel-Haenszel Procedure". Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1395842816.
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Bolesworth, Karen, and Susan Tufts. "Social welfare policy and the crisis of hunger." CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/1891.
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The Personal Responsibility and Work Opportunity Reconciliation Act of 1996 has lead to reduced welfare assistance to the needy. This thesis analyzes how families have become increasingly homeless and hungry during the welfare reform years.
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Sheen, Peter Bernard. "Managing Intellectual Property and Licensing: A Study on Cooperative Research Centres." Queensland University of Technology, 2005. http://eprints.qut.edu.au/16010/.
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This thesis examines the perceived importance by two-tiered management of Cooperative Research Centres (CRCs) for managing a range of intellectual property issues. Fifty survey items are presented to the executive directors and commercialization managers of 62 CRCs. The survey items are categorized under four themes: relationships with collaborators, project management; design and implementation of agreements; and specific licensing issues. An analysis of the data, using a series of independent samples t-tests, repeated measures t-tests, chi-square tests for independence or relatedness and goodness of fit, shows a range of results. There are significant differences between executive directors and commercialization managers on a number of issues. There are particular emphases or trends about certain issues for the whole sample of managers. These findings are compared with text analyses of 23 CRC strategic planning documents. This is done in order to explore any similarity, difference or nuance between what the managers say in response to the survey items, compared with what is stated in the codified policies of the CRCs. While there is a high degree of consistency among certain themes between the two sets of findings, the overall analysis points to the need for the CRCs to have a better understanding and practice of commercialization opportunities, especially through the involvement of third party commercial interests. It is argued that accommodating third party commercialization interests involves the application of an important knowledge economy principle that has an important bearing on the future economic viability and competitiveness of the CRCs.
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'Malebese, Mot'selisi Lilian. "The relationship between parental support and self-regulated learning behavior of Grade 12 learners in Lejweleputswa." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2013. http://hdl.handle.net/11462/183.
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Thesis (M. Education) -- Central University of Technology, Free State, 2013<br>The purpose of the study was to investigate the relationship between parental support and self-regulated learning behaviour of grade 12 learners. The study investigated support given to self-regulated learning of grade 12 learners. It gathered both quantitative and qualitative data. The researcher adopted the QUAN-qual model, which is also known as explanatory design. In this model quantitative data are collected first and are more heavily weighted than qualitative data.
The quantitative method investigated the relationship between parental support and grade 12 learners’ self-regulated learning behaviour. It also investigated how parental support contributed to learner self-regulated learning behaviour. Qualitative research design explained strategies schools used to encourage positive parental support in their children’s self-regulated learning. It also explained why parents did not offer their support to their children’s education despite the fact that the South African School Act of 1996 encouraged them to do so.
The population included grade 12 teachers and learners, as well as learners’ parents from different secondary schools in the Lejweleputswa district. The researcher administered questionnaires to 118 teachers and 218 learners, while 6 parents were interviewed. Teachers and learners were handed relevant questionnaires aimed at their level of participation in the survey. For quantitative data analysis the chi-square test was employed to test whether there were relationships between the variables. The study revealed that there was statistical significant relationship between parental support and learners’ self-regulated learning behaviour. Qualitative data was analysed making use of different analytical concepts used to guide researchers in qualitative data analysis. Although learners may acquire effective self-regulated learning strategies on their own, proper guidance from parents and teachers is very crucial, especially in the early stages of learning. The study established that regular general parent’s meetings, each term, help to facilitate improved learner performance. Amongst others, the researcher recommended that schools should introduce incentive for parental involvement in school matters.
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Ščerbakov, Jaroslav. "Statistinių hipotezių taikymas mokomųjų kompiuterių priemonių naudojimo matematikos pamokose analizei." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050622_131057-36373.
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The research is dealing with the problem of choosing right statistical criteria in order to analyze the concrete educological research information and to interpret the received results. The practical value of the research’s results could be described as: 1- the exact evaluation of the real situation, by researching the effectiveness of use of educational computer means at the lessons of mathematics, with the help of hypothesises; 2- the statistical criteria received at the time of the research can be used at the concrete future researches.
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Joly, Jean-Luc. "Contributions à la génération aléatoire pour des classes d'automates finis." Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2012/document.
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Le concept d’automate, central en théorie des langages, est l’outil d’appréhension naturel et efficace de nombreux problèmes concrets. L’usage intensif des automates finis dans un cadre algorithmique s ’illustre par de nombreux travaux de recherche. La correction et l’ évaluation sont les deux questions fondamentales de l’algorithmique. Une méthode classique d’ évaluation s’appuie sur la génération aléatoire contrôlée d’instances d’entrée. Les travaux d´écrits dans cette thèse s’inscrivent dans ce cadre et plus particulièrement dans le domaine de la génération aléatoire uniforme d’automates finis.L’exposé qui suit propose d’abord la construction d’un générateur aléatoire d’automates à pile déterministes, real time. Cette construction s’appuie sur la méthode symbolique. Des résultats théoriques et une étude expérimentale sont exposés.Un générateur aléatoire d’automates non-déterministes illustre ensuite la souplesse d’utilisation de la méthode de Monte-Carlo par Chaînes de Markov (MCMC) ainsi que la mise en œuvre de l’algorithme de Metropolis - Hastings pour l’ échantillonnage à isomorphisme près. Un résultat sur le temps de mélange est donné dans le cadre général .L’ échantillonnage par méthode MCMC pose le problème de l’évaluation du temps de mélange dans la chaîne. En s’inspirant de travaux antérieurs pour construire un générateur d’automates partiellement ordonnés, on montre comment différents outils statistiques permettent de s’attaquer à ce problème<br>The concept of automata, central to language theory, is the natural and efficient tool to apprehendvarious practical problems.The intensive use of finite automata in an algorithmic framework is illustrated by numerous researchworks.The correctness and the evaluation of performance are the two fundamental issues of algorithmics.A classic method to evaluate an algorithm is based on the controlled random generation of inputs.The work described in this thesis lies within this context and more specifically in the field of theuniform random generation of finite automata.The following presentation first proposes to design a deterministic, real time, pushdown automatagenerator. This design builds on the symbolic method. Theoretical results and an experimental studyare given.This design builds on the symbolic method. Theoretical results and an experimental study are given.A random generator of non deterministic automata then illustrates the flexibility of the Markov ChainMonte Carlo methods (MCMC) as well as the implementation of the Metropolis-Hastings algorithm tosample up to isomorphism. A result about the mixing time in the general framework is given.The MCMC sampling methods raise the problem of the mixing time in the chain. By drawing on worksalready completed to design a random generator of partially ordered automata, this work shows howvarious statistical tools can form a basis to address this issue
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Kegel, Anja. "Venture Performance and Motivation of Business Foundation - An empirical Study in the Free-state Saxony." Master's thesis, Hochschule für Technik und Wirtschaft Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:520-qucosa-159826.
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Die Zielstellung der Arbeit besteht darin zu untersuchen, in welchem Umfang Motivation und Opferbereitschaft eines Unternehmers auf die Leistungskraft des Unternehmens wirken, und inwieweit demographische Faktoren wie Geschlecht und Alter die persönlichen Ansichten des Unternehmers, dessen Motivation, dessen Opferbereitschaft und die Start-up-Hürden beeinflussen. Im Weiteren geht es darum, die Bedeutung des Unternehmertums für die Wirtschaft zu analysieren, vor allem in den fünf neuen Bundesländern und insbesondere in Sachsen. Untersuchungsergebnisse in Bezug auf Persönlichkeitsmerkmale des Unternehmers im Zusammenhang mit dem Erfolg des eigenen Unternehmens werden vorgestellt. Es werden Hypothesen über den Zusammenhang zwischen Motivation, Opferbereitschaft und den Unternehmenserfolg aufgestellt und mit Methoden der mathematischen Statistik beurteilt. Schließlich werden die wesentlichen Merkmale eines Unternehmers beschrieben. Um statistische Analysen durchzuführen und tragfähige Aussagen zu gewinnen, wurden zuerst Fragebögen am mehr als 100 neugegründete Unternehmen verschickt. Im Rücklauf kamen 102 Fragebögen in die engere Auswertung. Es wurden zwei Faktorenanalysen mit SPSS durchgeführt, wobei hier insgesamt 35 erfasste Merkmale (mit jeweils 5 Merkmalsausprägungen) zur Unternehmensgründung eingegangen sind und 7 Faktoren für die weitere Betrachtung ausgewählt wurden: - Grad der Unabhängigkeit - Priorität der Familie - Grad der Selbständigkeit - Politische Entscheidungsmotive - Priorität des Unternehmens - Konfliktpotential - Risiken im Lebensunterhalt Mithilfe des Chi-Quadrat-Unabhängigkeitstests wurde abschließend der paarweise Zusammenhang jeweils zwischen einem der genannten 7 Faktoren und den zwei für die Zielgröße „Erfolg des Unternehmen“ ausgewählten Merkmale „Umsatzwachstum“ und „Kapitalrückfluss – Investition“ untersucht, um hier wesentliche Abhängigkeiten aufzudecken<br>The purpose of this paper is to analyse the factors of successful entrepreneurship, whether or not age, sex or personal traits such as motivation and level of risk / sacrifice determine the outcome of business or if more external factors are the key drivers. Furthermore the research focusses on entrepreneurship in the New Laender, particularly Saxony, after the reunification and the importance for the economy in general. The research was done through interviews and mail-outs of questionnaires to more than 100 recently founded enterprises of which 102 replies were utilized in the final analyses. Hypotheses of potential correlation between personal traits and characteristics and success of business were analysed and tested using SPSS factor analyses. The SPSS analysis concentrated on 35 characteristics with 5 different values and an additional 7 factors: - Level of independence - Priority of family - Level of self-reliance - Political motivation in decision making - Priority of the business itself - Conflict potential - Level of risk taking Utilizing the ‚Chi-Square-Independence‘ - test further correlation analyses was performed to investigate the 7 factors and their individual relation / dependency with the two main characteristics Growth of Turnover and Return on Investment
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Lemonte, Artur Jose. "Estatística gradiente e refinamento de métodos assintóticos no modelo de regressão Birnbaum-Saunders." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/45/45133/tde-26102010-123617/.
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Rieck & Nedelman (1991) propuseram um modelo de regressão log-linear tendo como base a distribuição Birnbaum-Saunders (Birnbaum & Saunders, 1969a). O modelo proposto pelos autores vem sendo bastante explorado e tem se mostrado uma ótima alternativa a outros modelos propostos na literatura, como por exemplo, os modelos de regressão Weibull, gama e lognormal. No entanto, até o presente momento, não existe nenhum estudo tratando de refinamentos para as estatísticas da razão de verossimilhanças e escore nesta classe de modelos de regressão. Assim, um dos objetivos desta tese é obter um fator de correção de Bartlett para a estatística da razão de verossimilhanças e um fator de correção tipo-Bartlett para a estatística escore nesse modelo. Estes ajustes melhoram a aproximação da distribuição nula destas estatísticas pela distribuição qui-quadrado de referência. Adicionalmente, objetiva-se obter ajustes para a estatística da razão de verossimilhanças sinalizada. Tais ajustes melhoram a aproximação desta estatística pela distribuição normal padrão. Recentemente, uma nova estatística de teste foi proposta por Terrell (2002), a qual o autor denomina estatística gradiente. Esta estatística foi derivada a partir da estatística escore e da estatística de Wald modificada (Hayakawa & Puri, 1985). A combinação daquelas duas estatísticas resulta em uma estatística muito simples de ser calculada, não envolvendo, por exemplo, nenhum cálculo matricial como produto e inversa de matrizes. Esta estatística foi recentemente citada por Rao (2005): \"The suggestion by Terrell is attractive as it is simple to compute. It would be of interest to investigate the performance of the [gradient] statistic.\" Caminhando na direção da sugestão de Rao, outro objetivo da tese é obter uma expansão assintótica para a distribuição da estatística gradiente sob uma sequência de alternativas de Pitman convergindo para a hipótese nula a uma taxa de convergência de n^{-1/2} utilizando a metodologia desenvolvida por Peers (1971) e Hayakawa (1975). Em particular, mostramos que, até ordem n^{-1/2}, a estatística gradiente segue distribuição qui-quadrado central sob a hipótese nula e distribuição qui-quadrado não central sob a hipótese alternativa. Também temos como objetivo comparar o poder local deste teste com o poder local dos testes da razão de verossimilhanças, de Wald e escore. Finalmente, aplicaremos a expansão assintótica derivada na tese em algumas classes particulares de modelos.<br>The Birnbaum-Saunders regression model is commonly used in reliability studies.We address the issue of performing inference in this class of models when the number of observations is small. Our simulation results suggest that the likelihood ratio and score tests tend to be liberal when the sample size is small. We derive Bartlett and Bartlett-type correction factors which reduce the size distortion of the tests. Additionally, we also consider modified signed log-likelihood ratio statistics in this class of models. Finally, the asymptotic expansion of the distribution of the gradient test statistic is derived for a composite hypothesis under a sequence of Pitman alternative hypotheses converging to the null hypothesis at rate n^{-1/2}, n being the sample size. Comparisons of the local powers of the gradient, likelihood ratio, Wald and score tests reveal no uniform superiority property.
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Pulido, Herrera Edith. "Improving Data Fusion in User Positioning Systems." Doctoral thesis, Universitat Jaume I, 2009. http://hdl.handle.net/10803/10485.
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A fault detection and correction methodology for user positioning systems based on Kalman filtering is presented in this thesis. To develop this methodology, various aspects of the design of positioning systems are taken into account, such as the dynamic models of the systems, the definition of the estimation technique, the available technology and the environment (to identify disturbances that can affect the systems).<br/>In the first phase, the available technologies were identified, and the algorithms and the physical-mathematical models were defined for the positioning systems for both indoor and outdoor environments. The Dead Reckoning (DR) algorithm was included for this reason, because it can be applied in both environments. This algorithm allows the pedestrian's position to be obtained while s/he is walking. Given that one of the main parameters of DR is the pedestrian's step length, a careful analysis was carried out to determine it. Algorithms that allow, first, detection of a step and, second, calculation of its length are therefore presented here.<br/>An integrated system based on UWB and inertial technologies (IMU) is proposed for indoor environments. This system uses the information about the step length to improve the information provided by the UWB system. The system that was defined for outdoor environments is a GPSIMU system based on the DR algorithm. Data fusion is carried out by means of Kalman filtering for both systems. In the GPSIMUDR system, the errors of the azimuth bias and the step length are obtained by means of Kalman filtering, which allows the DR parameters to be corrected and, consequently, the pedestrian's position can be obtained with greater accuracy.<br/>In the next phase, the fault detection and correction methodology is developed. This is based on the principles of causal diagnosis using the theory of possibility. This methodology is proposed in order to prevent the introduction of erroneous information into the Kalman filter. In order to carry this out, failure states of the sensor systems are defined and corrective measures are applied when one or more of those states are present. These states are defined taking into account the empirical knowledge of the behaviour of the system. The performance of the filters was also monitored. This consists in the continuous evaluation of their innovations and, in case of inconsistency, corrective measures are applied to the parameters of the filters.<br/>The experiments, for the proposed systems, presented results that improved their initial response to a considerable degree. For the UWBIMU system, an analysis that involves the detection of inconsistencies of the filter is presented, while for the GPSIMUDR system the fault detection and correction methodology is applied. In the UWBIMU system, the corrective measures introduced into to the Kalman filter allowed both consistent filtering and a soft signal to be obtained, i.e. most of the reflections of the signal provided by the UWB system were eliminated. The results of the GPSIMUDR system indicated that by implementing the methodology developed here, consistent filtering was obtained and the values of the azimuth and the step length were corrected properly. As a result more exact pedestrian trajectories were obtained.
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Serrano, Sara Coelho. "Analysis of the reinsurance treaty for a workers? Compensation portfolio." Master's thesis, Instituto Superior de Economia e Gestão, 2015. http://hdl.handle.net/10400.5/8995.
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Mestrado em Ciências Actuariais<br>Este relatório assenta numa análise à sustentabilidade do ramo de Acidentes de Trabalho no contexto do estágio realizado na Allianz Portugal. Inicialmente é explicado o contexto legal do ramo de forma a compreender-se melhor as características específicas deste.
Por conseguinte serão detalhados os modelos e pressupostos, utilizados pela Companhia, no cálculo das provisões técnicas de Acidentes de Trabalho. O foco principal será na análise ao tratado de resseguro de Excedente de danos que cobre os custos com sinistros de Acidentes de Trabalho e o seu impacto no resultado técnico. A análise é feita com base no Modelo de Risco coletivo e em indicadores estatísticos como o Value-at-Risk, coeficiente de assimetria, variância e valor esperado.<br>This report resumes the analysis of the sustainability of Worker's Compensation within the internship at Allianz Portugal. The legal framework of the business is primarily explained as it is important to understand the business specifications.
Models and assumptions used, by the Company, in the calculation of technical provisions for Worker's Compensation will be detailed. The main focus of this paper will be in the analysis of the Excess of Loss reinsurance treaty that covers costs from Worker's Compensation and its impact in the technical result. The analysis is based on the Collective Risk Model and statistical indicators, such as Value-at-Risk, skewness coefficient, variance and expected value.
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Cavassin, Rebecca Tarasiuk Borba. "Monitoramento da satisfação de clientes em empreendimentos imobiliários." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/1199.
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A tendência à implantação e certificação de Sistemas de Gestão da Qualidade (SGQ) tem sido estudada pelo mundo, pois há diversos autores que citam como uma das maiores influências para a implantação desse sistema a melhora do relacionamento com o cliente. Porém, apesar da crença na relação entre a qualidade, satisfação do cliente e retorno econômico, é preciso uma melhor compreensão nesta área. Este trabalho tem por objetivo avaliar a relação entre a implantação de SGQ e a satisfação dos clientes de empreendimentos imobiliários novos na cidade de Curitiba. Para a obtenção de dados, a fim de sustentar este trabalho, realizou-se um estudo preliminar e um trabalho de levantamento quantitativo de dados. A primeira etapa buscou informações relevantes para a construção e a validação do questionário utilizado na segunda parte, a qual se destinou à captação da percepção do cliente final. Foram obtidos 386 questionários respondidos no período de março a novembro de 2013. Por meio de Análises Descritivas dos dados, verifica-se que amostra demonstra ser fiel ao universo da pesquisa, sem haver discrepâncias significativas. Para a realização da análise da amostra, considerou-se a abordagem definida pelos autores Hair et al. (2010), em que um modelo de satisfação do cliente só é plenamente compreendido quando se estuda: a variável, os construtos e os relacionamentos entre duas ou mais variáveis. Portanto, realizaram-se diversas Análises Descritivas, bem como os testes estatísticos Qui-Quadrado e Análise Discriminante, a fim de estudar as variáveis componentes da satisfação. Em seguida os constructos, os quais foram obtidos por meio da Análise Fatorial. Foram estudados por fim, a relação entre as variáveis através da Regressão Linear Múltipla dos dados. Como resultado desta pesquisa, percebeu-se que não é possível basear a conclusão final do estudo somente pela média da satisfação global, pois esta pode encobrir outros resultados. Além disso, verificou-se que as variáveis padrão do imóvel e tipo de gestão (com ou sem SGQ) podem influenciar na satisfação do cliente. Como exemplo, os participantes de empreendimentos construídos sem SGQ mostraram-se mais satisfeitos do que os daqueles construídos com SGQ e o grupo dos participantes de empreendimentos com padrão baixo, os mais insatisfeitos dentre todos os padrões. Por meio da Análise Fatorial, foram encontrados 4 fatores: a) comunicação com a empresa, b) produto, c) localização, d) projeto, bem como um fator geral, a satisfação global. Em relação à insatisfação, esta é evidente nos fatores que apresentaram maior importância, comunicação com a empresa e produto. Acredita-se que embora este estudo seja válido apenas para Curitiba, o desenvolvimento e a estrutura deste modelo oferecem uma referência consistente para a avaliação da satisfação do cliente na construção civil em outros contextos.<br>The tendency to implementation and certification of quality management systems have been studied around the world, many authors cite as one of the biggest influences the improve the customer relationship. Despite the belief in the link between quality, customer satisfaction and economic returns, we need to learn more about this area. The propose of this study is to evaluate customer satisfaction of new buildings in the city of Curitiba. To get the data, we conducted a preliminary study and a quantitative survey. The first step searched for information to the construction and validation of the questionnaire used in the second part, which was destined to final customer. We obtained 386 questionnaires during March to November 2013. And through descriptive data analysis, we found that sample is true to the universe studied, because there are not significant differences. To perform the analysis of the sample, we considered the approach defined by the authors Hair et al. (2010), where a model of customer satisfaction is completely understood only when we studied: the variable, constructs, and relationships between two or more variables. Therefore, we performed several descriptive analyzes and the chi-square test in order to study the variable components of satisfaction. Next the constructs, which were obtained from through factor analysis. And last, we check the relationship between variables through multiple linear regressions of the data. As a result of this work, we noticed that it is not possible to rely only on the average overall satisfaction, because it may mask other results. In addition, we found that the variables: the default of the building and type of management (with or without TQM), can influence customer satisfaction. For example, participants of buildings built without TQM are more satisfied than those built with TQM, and the group of participants of buildings of low default is the most unhappy of all the defaults. Through factor analysis, we found four factors, communication with the company, product, location, design, as well as a general factor, overall satisfaction. The dissatisfaction is evident in the two most important factors: communication with the company and product. It is believed that, although our study is valid only for Curitiba, the development and structure of this model provide a great reference for the evaluation of customer satisfaction in other settings of the construction industry.<br>5000
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Hsu, Yin-Pei, and 許英珮. "A Comparison Study of Likelihood Ratio Test and Pearson's Chi- square Test." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/18312274346598045493.
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Marwaha, Shubra. "Detection of burst noise using the chi-squared goodness of fit test." Thesis, 2009. http://hdl.handle.net/2152/ETD-UT-2009-08-180.
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Statistically more test samples obtained from a single chip would give a better picture of the various noise processes present. Increasing the number of samples while testing one chip would however lead to an increase in the testing time, decreasing the overall throughput. The aim of this report is to investigate the detection of non-Gaussian noise (burst noise) in a random set of data with a small number of samples.
In order to determine whether a given set of noise samples has non-Gaussian noise processes present, a Chi-Squared ‘Goodness of Fit’ test on a modeled set of random data is presented. A discussion of test methodologies using a single test measurement pass as well as two passes is presented from the obtained simulation results.<br>text
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Zeng, Chun-Yen, and 鄭俊彥. "K-sample comparative multinomial trial:A quantitative evaluation of the Pearson's chi-squared test." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/44912360081968976776.
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碩士<br>國立高雄大學<br>統計學研究所<br>100<br>Fisher's exact test (FET) is a conditional method that is frequently
used to analyze data in a 2×2 table for small samples. This
test is conservative and attempts have been made to modify the test
to make it less conservative. For example, Crans and Shuster (2008)
proposed adding more points in the rejection region to make the test
more powerful. Additionally, they propose an adjusted method that defines new significance levels α*=α+ε, where α is pre-specified and ε is a small positive number.
The adjustment uniformly improves the test size,
rasing the actual probability of type I error,
where the sequence of the possible outcomes for the rejection region is based on the p-value of FET.
Early in year 1985, Suissa and Shuster had proposed the exact unconditional method (EUM) used the t-test statistic with pooled and un-pooled variance, respectively, to derive a rejection region for the hypothesis.
In addition, up to now, there is no conclusion in which of these tests gives larger power,
we will give a series of numerical comparison to these two tests.
Later, we also extend these two test procedures to high dimensional problem.
Specifically, the extensions use several different combinations
to merge the information to form an univariate test statistic.
Lastly, some figures are presented to show the pattern changes of the power functions of these extensions.
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Chang, Yu-Mei, and 張毓美. "Association Based Classification Using Chi-Square Independence Test." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/27786273173391473014.
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碩士<br>國立中央大學<br>資訊工程研究所<br>90<br>For many years, classification s one of the key problems in machine learning research. Since association rule mining is an important and highly active data mining research, there are more and more classification methods based on association rule mining techniques. In this thesis, we study several association based classification methods and provide the comparison of these classifiers. We present a new method, called ACC (i.e. Association based Classification using Chi-square Independence test), to solve the problems of classification.
ACC finds frequent and interesting itemsets, which describe the relations between attributes. Moreover, it applies chi-square independence test to remain class-related itemsets for predicting new data objects. Besides, ACC provides an approach that considers the probability of missing value occurrence to solve the problem of missing value. Our method is experimented on 13 datasets from UCI machine learning database repository. We compare ACC with NB and LB, the state-of-the-art classifiers and the experimental results show that our method is a highly effective, accurate classifier.
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Lin, Pei Chun, and 林佩君. "Fuzzy Chi-square Test Statistic for goodness-of-fit." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/17929009994864911856.
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碩士<br>國立政治大學<br>應用數學研究所<br>95<br>In the analysis of research data, the investigator often needs to decide whether several independent samples may be regarded as having come from the same population. The most commonly used statistic is Pearson’s statistic. However, traditional statistics reflect the result from a two-valued logic concept. If we want to survey sampling with fuzzy logic concept, is it still appropriate to use the traditional -test for analysing those fuzzy sample data? Through this concept, we try to use a traditional statistic method to find out a formula, called fuzzy , that enables us to deal with those fuzzy sample data. The result shows that we can use the formula to test hypotheses about probabilities of various outcomes in fuzzy sample data.
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"A Study of Components of Pearson's Chi-Square Based on Marginal Distributions of Cross-Classified Tables for Binary Variables." Doctoral diss., 2018. http://hdl.handle.net/2286/R.I.49121.
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abstract: The Pearson and likelihood ratio statistics are well-known in goodness-of-fit testing and are commonly used for models applied to multinomial count data. When data are from a table formed by the cross-classification of a large number of variables, these goodness-of-fit statistics may have lower power and inaccurate Type I error rate due to sparseness. Pearson's statistic can be decomposed into orthogonal components associated with the marginal distributions of observed variables, and an omnibus fit statistic can be obtained as a sum of these components. When the statistic is a sum of components for lower-order marginals, it has good performance for Type I error rate and statistical power even when applied to a sparse table. In this dissertation, goodness-of-fit statistics using orthogonal components based on second- third- and fourth-order marginals were examined. If lack-of-fit is present in higher-order marginals, then a test that incorporates the higher-order marginals may have a higher power than a test that incorporates only first- and/or second-order marginals. To this end, two new statistics based on the orthogonal components of Pearson's chi-square that incorporate third- and fourth-order marginals were developed, and the Type I error, empirical power, and asymptotic power under different sparseness conditions were investigated. Individual orthogonal components as test statistics to identify lack-of-fit were also studied. The performance of individual orthogonal components to other popular lack-of-fit statistics were also compared. When the number of manifest variables becomes larger than 20, most of the statistics based on marginal distributions have limitations in terms of computer resources and CPU time. Under this problem, when the number manifest variables is larger than or equal to 20, the performance of a bootstrap based method to obtain p-values for Pearson-Fisher statistic, fit to confirmatory dichotomous variable factor analysis model, and the performance of Tollenaar and Mooijaart (2003) statistic were investigated.<br>Dissertation/Thesis<br>Doctoral Dissertation Statistics 2018
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Wang, Guan-Siang, and 王冠翔. "Modified Wald test corresponding to maximally sleceted chi-square statistic." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/42948972662242064421.
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碩士<br>國立中興大學<br>統計學研究所<br>98<br>Customarily, we use contingency table analysis to judge whether variables are independent or not. We are used to taking a threshold which leads a maximum chi-square statistic. However, it had been proved that the maximum statistic did not follow a chi-square distribution anymore. Adopting the modified distribution from Miller R. and Siegmund D. (1982), then we applies it to Wald test of logistic regression corresponding to maximally selected chi-square statistic. Via a series of simulation, we reduce the proportion of committing type I error by using the modified distribution. It is to be regretted that when we deal with the correlated covariates, and the proportion no longer maintains at given 0.05. In this thesis, we''ll take a real data for example to illustrate how the modified distribution compared with chi-square distribution with df 1 of Wald test works. There is still a problem to be solved: correlated covariates. Furthermore, we should devote more attention to this issue.
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Yu-Jui-Tseng and 曾于芮. "Finite sample property of chi-square test data for ranking." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/4ma98z.
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碩士<br>淡江大學<br>數學學系碩士在職專班<br>106<br>Ranking data is often concerned about whether it has the same preference in life. In Anderson (1959), the contingency table method is used, and Schalch (1979) uses the incomplete block design, Jyh-Shyang Wu & Wen-Shuenn Deng ( 2017) uses partial sorting data, sorts into an N×k contingency table from the perspective of the row, and then uses the collinear table to check the statistic to establish a statistic.
This paper will continue Jyh-Shyang Wu & Wen-Shuenn Deng (2017), promote the column into a N × k contingency table, the statistic is changed to the statistic family, which means that the preference is not Appear in a uniform chance.