Academic literature on the topic 'Pearson's Chi square test'

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.

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.

Made available in DSpace on 2016-03-15T19:32:34Z (GMT). No. of bitstreams: 1 Ricardo Cavalcanti Alves.pdf: 1472492 bytes, checksum: 191a6c7b13b5d0386ac7e4edda2748c7 (MD5) 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.

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

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.