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Journal articles on the topic "Superior Predictive Ability test"
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Hansen, Peter Reinhard. "A Test for Superior Predictive Ability." Journal of Business & Economic Statistics 23, no. 4 (October 2005): 365–80. http://dx.doi.org/10.1198/073500105000000063.
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Cai, Zongwu, Jiancheng Jiang, Jingshuang Zhang, and Xibin Zhang. "A new semiparametric test for superior predictive ability." Empirical Economics 48, no. 1 (December 3, 2014): 389–405. http://dx.doi.org/10.1007/s00181-014-0887-6.
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Cenciarelli, Velia Gabriella, Giulio Greco, and Marco Allegrini. "Does intellectual capital help predict bankruptcy?" Journal of Intellectual Capital 19, no. 2 (March 12, 2018): 321–37. http://dx.doi.org/10.1108/jic-03-2017-0047.
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Purpose The purpose of this paper is to explore whether intellectual capital affects the probability that a particular firm will default. The authors also test whether including intellectual capital performance in bankruptcy prediction models improves their predictive ability. Design/methodology/approach Using a sample of US public companies from the period stretching from 1985 to 2015, the authors test whether intellectual capital performance reduces the probability of bankruptcy. The authors use the VAIC as an aggregate measure of corporate intellectual capital performance. Findings The findings show that the intellectual capital performance is negatively associated with the probability of default. The findings also indicate that the bankruptcy prediction models that include intellectual capital have a superior predictive ability over the standard models. Research limitations/implications This paper contributes to prior research on intellectual capital and firm performance. To the best of the knowledge, this is the first study to show that the benefits of intellectual capital extend from superior performance to long-term financial stability. The research can also contribute to bankruptcy studies. By using a time frame covering decades, the findings suggest that intellectual capital performance measures can be included in bankruptcy prediction models and can effectively complement traditional performance measures. Originality/value This paper highlights that intellectual capital is associated with long-term financial stability and a lower bankruptcy risk. Firms realising the potential of their intellectual capital can produce a virtuous circle between higher performance and greater financial stability.
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Lv, Yang, Ning Pu, Wei-lin Mao, Wen-qi Chen, Huan-yu Wang, Xu Han, Yuan Ji, et al. "Development of predictive prognostic nomogram for NECs of rectum on population-based exploration." Endocrine Connections 7, no. 11 (November 2018): 1178–85. http://dx.doi.org/10.1530/ec-18-0353.
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Aim We aim to investigate the clinical characteristics of the rectal NECs and the prognosis-related factors and construct a nomogram for prognosis prediction. Methods The data of 41 patients and 1028 patients with rectal NEC were retrieved respectively from our institution and SEER database. OS or PFS was defined as the major study outcome. Variables were compared by chi-square test and t-test when appropriate. Kaplan–Meier analysis with log-rank test was used for survival analysis and the Cox regression analysis was applied. The nomogram integrating risk factors for predicting OS was constructed by R to achieve superior discriminatory ability. Predictive utility of the nomogram was determined by concordance index (C-index) and calibration curve. Results In the univariate and multivariate analyses, tumor differentiation, N stage, M stage and resection of primary site were identified as independent prognostic indicators. The linear regression relationship was found between the value of Ki-67 index and the duration of OS (P < 0.05). Furthermore, the independent prognostic factors were added to formulate prognostic nomogram. The constructed nomogram showed good performance according to the C-index. Conclusions Contrary to WHO classification guideline, we found that the rectal NEC diseases are heterogeneous and should be divided as different categories according to the pathological differentiation. Besides, the nomogram formulated in this study showed excellent discriminative capability to predict OS for those patients. More advanced predictive model for this disease is required to assist risk stratification via the formulated nomogram.
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Jiang, Brian Gabriel, Dong-Wook Kim, Lee-Yung Shih, Charles Chuah, Hein Than, Ming-Chung Kuo, HuiHua Li, et al. "Sokal Risk Score Is Superior to Hasford and EUTOS in Determining Survival Outcomes for Newly Diagnosed Chronic Phase Chronic Myeloid Leukemia Patients." Blood 126, no. 23 (December 3, 2015): 4044. http://dx.doi.org/10.1182/blood.v126.23.4044.4044.
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Abstract Despite being developed in eras when standard treatments for Chronic Phase Chronic Myeloid Leukemia (CP-CML) differ, Sokal, Hasford, and European Treatment and Outcome Study (EUTOS) scores each remain in use for predicting survival outcomes. The European LeukemiaNet (ELN) 2013 guidelines state that no one score is superior to the other. Furthermore, no studies have examined how a combination of scores may improve prognostic value. This retrospective, multicenter study compared the scores, individually and in combination, on predicting Overall Survival (OS), Progression-Free Survival (PFS) and Event-Free Survival (EFS) for CP-CML patients in Singapore General Hospital (Singapore), Seoul St. Mary's Hospital (South Korea) and Chang Gung Memorial Hospital (Taiwan). A total of 1222 newly diagnosed CP-CML patients (2013 ELN criteria) between July 1998 to December 2013 with follow-up period ≥18 months were reviewed. OS was defined as death from any cause, PFS was defined as transformation to accelerated or blastic phase and CML-related death. EFS was defined as failure according to the 2009 ELN criteria, treatment changes, progression, and death. Log likelihood ratio (LR) test of nested models was performed to compare dual combination scores with its individual components. Adequacy index was used to quantify the percentage of variation explained by each pair of scores. Harrell's c-index was also calculated to evaluate the predictive ability of the scores. Linear contrast test was used to further stratify the individual risk groups in dual combination scores. For OS, comparison of Sokal + EUTOS vs. EUTOS (LR 40.44 vs. 0.49) or Sokal + Hasford vs. Hasford (LR 31.78 vs. 11.81) showed that the combined model was significantly better than the individual models alone (p-value<0.01 for both). However, comparison of Sokal + EUTOS vs. Sokal or Sokal + Hasford vs. Sokal was not significantly better. Comparison of Hasford + EUTOS vs. EUTOS was significantly better (LR 21.37 vs. 0.92, p-value<0.01). Thus, for OS, the predictive ability order of the models are Sokal>Hasford>EUTOS, which are supported by Harrell's c-indices of 0.665, 0.591, 0.514, respectively. Similar predictive ability order for individual scores were also drawn for EFS (refer to table 1). For PFS, comparison of Sokal + Hasford vs. Hasford showed the combined model was significantly better (LR 34.05 vs. 12.32, p-value<0.01). However comparison of Sokal + Hasford vs. Sokal was not significantly better, indicating the predictive ability of Sokal>Hasford, which is in agreement with the c-indices (0.620 vs. 0.569, respectively). Comparison of Sokal + EUTOS to either Sokal or EUTOS alone was both significantly better (LR 42.50 vs. 35.76, LR 42.50 vs. 20.33, respectively; p-value<0.01 for both). This is supported by similar c-indices for Sokal and EUTOS individually (0.620 and 0.621, respectively). However, in the combination of Sokal + EUTOS, Sokal explained 84.1% of the variation while EUTOS explained 47.8%. Thus, for PFS, the predictive ability of Sokal is superior to EUTOS or Hasford. When analyzing dual combination scores, Sokal + EUTOS combined had the highest c-indices for OS, PFS and EFS (0.758, 0.705, 0.621) compared to EUTOS + Hasford and Sokal + Hasford. Linear contrast to rank Sokal + EUTOS in combination produced various valid paired orders, of which the order of SokalLow EUTOSLow, SokalIntermediate EUTOSLow, SokalIntermediate EUTOSHigh, SokalHigh EUTOSLow, SokalHigh EUTOSHighhad a hazard ratio of 4.47, 4.08, 2.26 for OS, PFS and EFS respectively (p-value<0.01 for all). Contrary to the ELN 2013 guidelines that no single score is superior, our data shows that Sokal is superior in predicting OS, PFS and EFS in CP-CML. Dual score combinations are capable of improving prognostic ability, with Sokal + EUTOS in combination being the best to predict survival outcomes. Table 1. Log likelihood ratios of dual combination scores versus individual scores. Survival Outcome Log Likelihood ratio (p-value) EUTOS + SOKAL EUTOS SOKAL OS 40.44 0.49 (<0.01) 38.66 (0.18) PFS 42.50 20.33 (<0.01) 35.76 (<0.01) EFS 74.66 11.32 (<0.01) 73.49 (0.28) SOKAL + HASFORD SOKAL HASFORD OS 31.78 31.31 (0.79) 11.81 (<0.01) PFS 34.05 33.08 (0.61) 12.32 (<0.01) EFS 57.94 55.85 (0.35) 32.24 (<0.01) EUTOS + HASFORD EUTOS HASFORD OS 21.37 0.92 (<0.01) 20.87 (0.48) PFS 32.07 23.65 (<0.01) 20.22 (<0.01) EFS 46.35 12.34 (<0.01) 44.17 (0.14) Disclosures Shih: Novartis: Research Funding. Chuah:Novartis: Honoraria; Children International: Honoraria; Bristol Meyers Squibb: Honoraria. Goh:Roche: Honoraria; Janssen: Honoraria, Research Funding; Gilead Sciences: Honoraria; Sanofi: Honoraria; Novartis: Honoraria, Research Funding; Bristol-Myers Squibb: Honoraria; Celgene: Honoraria.
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BENEDICT, K. M., S. P. GOW, R. J. REID-SMITH, C. W. BOOKER, T. A. McALLISTER, and P. S. MORLEY. "Latent class comparison of test accuracy when evaluating antimicrobial susceptibility using disk diffusion and broth microdilution to testEscherichia coliandMannheimia haemolyticaisolates recovered from beef feedlot cattle." Epidemiology and Infection 142, no. 11 (January 24, 2014): 2314–25. http://dx.doi.org/10.1017/s0950268813003300.
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SUMMARYThe study objective was to use Bayesian latent class analysis to evaluate the accuracy of susceptibility test results obtained from disk diffusion and broth microdilution using bacteria recovered from beef feedlot cattle. Isolates ofEscherichia coliandMannheimia haemolyticawere tested for susceptibility to ampicillin, ceftiofur, streptomycin, sulfisoxazole, tetracycline, and trimethoprim-sulfamethoxazole. Results showed that neither testing method was always or even generally superior to the other. Specificity (ability to correctly classify non-resistant isolates) was extremely high for both testing methods, but sensitivity (ability to correctly classify resistant isolates) was lower, variable in the drugs evaluated, and variable between the two bacterial species. Predictive values estimated using Bayesian Markov chain Monte Carlo models showed that the ability to predict true susceptibility status was equivalent for test results obtained with the two testing methods for some drugs, but for others there were marked differences between results obtained from disk diffusion and broth microdilution tests.
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Altarazi, Safwan, Rula Allaf, and Firas Alhindawi. "Machine Learning Models for Predicting and Classifying the Tensile Strength of Polymeric Films Fabricated via Different Production Processes." Materials 12, no. 9 (May 7, 2019): 1475. http://dx.doi.org/10.3390/ma12091475.
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In this study, machine learning algorithms (MLA) were employed to predict and classify the tensile strength of polymeric films of different compositions as a function of processing conditions. Two film production techniques were investigated, namely compression molding and extrusion-blow molding. Multi-factor experiments were designed with corresponding parameters. A tensile test was conducted on samples and the tensile strength was recorded. Predictive and classification models from nine MLA were developed. Performance analysis demonstrated the superior predictive ability of the support vector machine (SVM) algorithm, in which a coefficient of determination and mean absolute percentage error of 96% and 4%, respectively were obtained for the extrusion-blow molded films. The classification performance of the MLA was also evaluated, with several algorithms exhibiting excellent performance.
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Senders, Joeky T., Patrick Staples, Alireza Mehrtash, David J. Cote, Martin J. B. Taphoorn, David A. Reardon, William B. Gormley, Timothy R. Smith, Marike L. Broekman, and Omar Arnaout. "An Online Calculator for the Prediction of Survival in Glioblastoma Patients Using Classical Statistics and Machine Learning." Neurosurgery 86, no. 2 (October 5, 2019): E184—E192. http://dx.doi.org/10.1093/neuros/nyz403.
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Abstract BACKGROUND Although survival statistics in patients with glioblastoma multiforme (GBM) are well-defined at the group level, predicting individual patient survival remains challenging because of significant variation within strata. OBJECTIVE To compare statistical and machine learning algorithms in their ability to predict survival in GBM patients and deploy the best performing model as an online survival calculator. METHODS Patients undergoing an operation for a histopathologically confirmed GBM were extracted from the Surveillance Epidemiology and End Results (SEER) database (2005-2015) and split into a training and hold-out test set in an 80/20 ratio. Fifteen statistical and machine learning algorithms were trained based on 13 demographic, socioeconomic, clinical, and radiographic features to predict overall survival, 1-yr survival status, and compute personalized survival curves. RESULTS In total, 20 821 patients met our inclusion criteria. The accelerated failure time model demonstrated superior performance in terms of discrimination (concordance index = 0.70), calibration, interpretability, predictive applicability, and computational efficiency compared to Cox proportional hazards regression and other machine learning algorithms. This model was deployed through a free, publicly available software interface (https://cnoc-bwh.shinyapps.io/gbmsurvivalpredictor/). CONCLUSION The development and deployment of survival prediction tools require a multimodal assessment rather than a single metric comparison. This study provides a framework for the development of prediction tools in cancer patients, as well as an online survival calculator for patients with GBM. Future efforts should improve the interpretability, predictive applicability, and computational efficiency of existing machine learning algorithms, increase the granularity of population-based registries, and externally validate the proposed prediction tool.
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Goulden, Robert, Marie-Claire Hoyle, Jessie Monis, Darran Railton, Victoria Riley, Paul Martin, Reynaldo Martina, and Emmanuel Nsutebu. "qSOFA, SIRS and NEWS for predicting inhospital mortality and ICU admission in emergency admissions treated as sepsis." Emergency Medicine Journal 35, no. 6 (February 21, 2018): 345–49. http://dx.doi.org/10.1136/emermed-2017-207120.
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BackgroundThe third international consensus definition for sepsis recommended use of a new prognostic tool, the quick Sequential Organ Failure Assessment (qSOFA), based on its ability to predict inhospital mortality and prolonged intensive care unit (ICU) stay in patients with suspected infection. While several studies have compared the prognostic accuracy of qSOFA to the Systemic Inflammatory Response Syndrome (SIRS) criteria in suspected sepsis, few have compared qSOFA and SIRS to the widely used National Early Warning Score (NEWS).MethodsThis was a retrospective cohort study carried out in a UK tertiary centre. The study population comprised emergency admissions in whom sepsis was suspected and treated. The accuracy for predicting inhospital mortality and ICU admission was calculated and compared for qSOFA, SIRS and NEWS.ResultsAmong 1818 patients, 53 were admitted to ICU (3%) and 265 died in hospital (15%). For predicting inhospital mortality, the area under the receiver operating characteristics curve for NEWS (0.65, 95% CI 0.61 to 0.68) was similar to qSOFA (0.62, 95% CI 0.59 to 0.66) (test for difference, P=0.18) and superior to SIRS (P<0.001), which was not predictive. The sensitivity of NEWS≥5 (74%, 95% CI 68% to 79%) was similar to SIRS≥2 (80%, 95% CI 74% to 84%) and higher than qSOFA≥2 (37%, 95% CI 31% to 43%). The specificity of NEWS≥5 (43%, 95% CI 41% to 46%) was higher than SIRS≥2 (21%, 95% CI 19% to 23%) and lower than qSOFA≥2 (79%, 95% CI 77% to 81%). The negative predictive value was 88% (86%–90%) for qSOFA, 86% (82%–89%) for SIRS and 91% (88%–93%) for NEWS. Results were similar for the secondary outcome of ICU admission.ConclusionNEWS has equivalent or superior value for most test characteristics relative to SIRS and qSOFA, calling into question the rationale of adopting qSOFA in institutions where NEWS is already in use.
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van Niftrik, Christiaan H. B., Frank van der Wouden, Victor E. Staartjes, Jorn Fierstra, Martin N. Stienen, Kevin Akeret, Martina Sebök, et al. "Machine Learning Algorithm Identifies Patients at High Risk for Early Complications After Intracranial Tumor Surgery: Registry-Based Cohort Study." Neurosurgery 85, no. 4 (May 31, 2019): E756—E764. http://dx.doi.org/10.1093/neuros/nyz145.
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Abstract INTRODUCTION Reliable preoperative identification of patients at high risk for early postoperative complications occurring within 24 h (EPC) of intracranial tumor surgery can improve patient safety and postoperative management. Statistical analysis using machine learning algorithms may generate models that predict EPC better than conventional statistical methods. OBJECTIVE To train such a model and to assess its predictive ability. METHODS This cohort study included patients from an ongoing prospective patient registry at a single tertiary care center with an intracranial tumor that underwent elective neurosurgery between June 2015 and May 2017. EPC were categorized based on the Clavien-Dindo classification score. Conventional statistical methods and different machine learning algorithms were used to predict EPC using preoperatively available patient, clinical, and surgery-related variables. The performance of each model was derived from examining classification performance metrics on an out-of-sample test dataset. RESULTS EPC occurred in 174 (26%) of 668 patients included in the analysis. Gradient boosting machine learning algorithms provided the model best predicting the probability of an EPC. The model scored an accuracy of 0.70 (confidence interval [CI] 0.59-0.79) with an area under the curve (AUC) of 0.73 and a sensitivity and specificity of 0.80 (CI 0.58-0.91) and 0.67 (CI 0.53-0.77) on the test set. The conventional statistical model showed inferior predictive power (test set: accuracy: 0.59 (CI 0.47-0.71); AUC: 0.64; sensitivity: 0.76 (CI 0.64-0.85); specificity: 0.53 (CI 0.41-0.64)). CONCLUSION Using gradient boosting machine learning algorithms, it was possible to create a prediction model superior to conventional statistical methods. While conventional statistical methods favor patients’ characteristics, we found the pathology and surgery-related (histology, anatomical localization, surgical access) variables to be better predictors of EPC.
Dissertations / Theses on the topic "Superior Predictive Ability test"
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Karadag, Mehmet Ali. "Analysis Of Turkish Stock Market With Markov Regime Switching Volatility Models." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609787/index.pdf.
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In this study, both uni-regime GARCH and Markov Regime Switching GARCH (SW-GARCH) models are examined to analyze Turkish Stock Market volatility. We investigate various models to find out whether SW-GARCH models are an
improvement on the uni-regime GARCH models in terms of modelling and forecasting Turkish Stock Market volatility. As well as using seven statistical loss functions, we apply Superior Predictive Ability (SPA) test of Hansen (2005) and
Reality Check test (RC) of White (2000) to compare forecast performance of various models.
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Grube, Joyce A. "The Predictive Ability of the Allied Health Aptitude Test and Selected Characteristics upon Success on Certification Examinations in Allied Health." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1419261632.
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Yapar, Taner. "A Study Of The Predictive Validity Of The Baskent University English Proficiency Exam Through The Use Of The Two-parameter Irt Model&." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1217629/index.pdf.
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The purpose of this study is to analyze the predictive power of the ability
estimates obtained through the two-parameter IRT model on the English
Proficiency Exam administered at BaSkent University in September 2001
(BUSPE 2001). As prerequisite analyses the fit of one- and two-parameter
models of IRT were investigated.
The data used for this study were the test data of all students (727) who took
BUSPE 2001 and the departmental English course grades of the passing
students.
At the first stage, whether the assumptions of IRT were met was
investigated. Next, the observed and theoretical distribution of the test data
was reviewed by using chi square statistics. After that, the invariance of
ability estimates across different sets of items and invariance of item
parameters across different groups of students were examined.
At the second stage, the predictive validity of BUSPE 2001 and its subtests
was analyzed by using both classical test scores and ability estimates of the
better fitting IRT model.
The findings revealed that the test met the assumptions of
unidimensionality, local independence and nonspeededness, the
assumptions of equal discrimination indices was not met. Whether the
assumption of minimal guessing was met remained vague. The chi square
statistics indicated that only the two parameter model fitted the test data.
The ability estimates were found to be invariant across different item sets
and the item parameters were found to be invariant across different groups
of students.
The IRT estimated predictive validity outweighed the predictive validity
calculated through classical total scores both for the whole test and its
subtests. The reading subtest was the best predictor of future performance in
departmental English courses among all subtests.
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Tavares, Diogo Filipe Lima. "Tests of intraday trading rules for the FTSE-100 index." Master's thesis, 2017. http://hdl.handle.net/1822/46508.
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Dissertação de mestrado em FinançasThe history of scientific research on the matter of the behavior of investors goes as far as the 16th century. However, most scrutiny and accomplishments occurred in the past century, and for most of that period the great debate has been centered on the question of market efficiency. The discussion has started in the 1960s and until this day there is still debate. Accordingly, in this study, I investigate if there is a technical trading rule, from a set of well-known trading rules, which can generate abnormal returns on the intraday data from the FTSE 100 Index from the period starting in January 2000 to December 2010. In other words, I try to attest for the validity of the weak form of the Efficient Market Hypothesis (EMH). More precisely, I define and implement 5680 trading rules that use past information and test if they provide abnormal returns, testing the statistical significance of the results with the Superior Predictive Ability (SPA) test by Hansen (2005). In that regard, the study allow to confirm the validity of the weak form of the EMH, since no tested rule can systematically outperform a buy and hold strategy. This result comes as no surprise considering the results achieve by similar studies, such as Marshall et al. (2008) Bajgrowicz and Scaillet (2012), Duvignage et al. (2013) and Chaboud et al. (2014). These results contrast with other studies that also use trading rules with intraday data and refute the EMH. However their conclusions were not based on robust tests to data snooping. In addition, further conclusions can be traced considering the duration and number of trades. The less time a portfolio is on the market for a given rule, the better is its performance. This can be indicative that the rules tested don’t generate value on their own merits, instead their results may simply be due to luck and to a small exposure to the market.
O início da história do conhecimento científico relativo ao comportamento do investidor é datado ao século XVI. Contudo, somente no último século o assunto tem vindo a ser alvo de maior atenção, e na maior parte desse período tem-se debatido a questão da eficiência dos mercados. A discussão começou na década de 60 e ainda hoje se debate. Por consequência, neste estudo tento investigar a existência de uma técnica de transação de um conjunto de técnicas, pertencentes à análise técnica, de conhecimento prévio e bem documentadas na literatura, que consiga gerar rendibilidades anormais nos dados intradiários do índice FTSE 100, no período com inicio em Janeiro de 2000 e término em Dezembro de 2010. Em detalhe, foram definidas e implementadas 5680 regras de transação que usam informação histórica, testando se geram rendibilidades anormais com o recurso ao teste SPA de Hansen (2005). Nesse sentido, o estudo permitiu confirmar a validade da forma fraca da teoria dos mercados eficientes, uma vez que nenhuma regra testada conseguiu, sistematicamente, bater o mercado. Este resultado não é de todo uma surpresa considerando os resultados obtidos por estudos do género, por exemplo Marshall et al. (2008) Bajgrowicz e Scaillet (2012), Duvignage et al. (2013) e Chaboud et al. (2014). Esses resultados contrastam com outros estudos que também usaram regras de transação com dados intradiários e refutaram a teoria dos mercados eficientes. Contudo, essas conclusões não se fundamentaram em testes de robustez ao snooping dos dados. Adicionalmente, podem-se presumir ulteriores conclusões tendo em consideração a duração e o número de transações. Quanto menor o tempo de exposição do portfolio no mercado para uma determinada regra, melhor é a sua performance. Isto pode ser sinal de que as regras testadas não conseguem gerar valor por si só, pelo contrário, os seus resultados parecem ser obtidos de uma combinação de aleatoriedade e pouca exposição ao mercado.
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Bliss, Stacy L. "Concurrent and Predictive Validity of the Universal Nonverbal Intelligence Test-Group Ability Test." 2008. http://trace.tennessee.edu/utk_graddiss/412.
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In order to determine the concurrent and predictive validity of the Universal Nonverbal Intelligence Test- Group Ability Test (UNIT-GAT; McCallum & Bracken, in press), the UNIT-GAT and the Naglieri Nonverbal Ability Test (NNAT; Naglieri, 1997a) were administered in counter-balanced order to 93 students. In addition, 40 students were rated on the Universal Nonverbal Intelligence – Gifted Screening Scales (UNIT-GSS; McCallum & Bracken, in press). The correlation coefficient of r = .36 between the UNITGAT total raw score and the NNAT was statistically significant at the p < .01 level. The UNIT-GAT scale score correlations with the NNAT total ranged from r = .18 for the Symbolic Scale to r= .53 (p< .01) for the Nonsymbolic Scale. The UNIT-GAT total raw score correlations with the UNIT-GSS composite and scales ranged from r = -.06 between both the Emotional and Science scales to r = .19 on the Creative Scale. None of the correlations were statistically significant. The correlations between the scales of the UNIT-GAT and composites of the UNIT-GSS ranged between r= -.05 (UNIT-GAT Memory Scale and UNIT-GSS General Aptitudes Composite) to r = .20 (UNIT-GAT Reasoning Scale and UNIT-GSS General Aptitudes Composite). Correlations between the scales of the UNIT-GAT and the scales of the UNIT-GSS ranged from r = -.30 between the UNIT-GAT Memory Scale and UNIT-GSS Emotional Scale to r = .25 between the UNIT-GAT Nonsymbolic Scale and UNIT-GSS Creative Scale.
Stepwise multiple regression analysis did not reveal any significant utility by the UNIT-GAT total raw score or the NNAT total raw score to predict teacher-ratings on the UNIT-GSS General Aptitude and Specific Academic Aptitude Composites. Implications and future directions for research are discussed.
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Lee, Yu-Chia, and 李友嘉. "An Empirical Study on Stepwise Regression,Reality Check and Superior Predictive Ability-Evidence from TAIEX." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/40887508297817139846.
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碩士國立中興大學
應用數學系所
95
The return is very complicated and hard to predict in the financial market. This article uses common technical analysis-momentum, trend line, relative strength index, moving average and some sentiment indicators -volatility index, put call ratio of open interest, put call ratio of volume to be variables of regression model. Moreover, we apply reality check (White, 2000), test for superior predictive ability (Hansen, 2005) and stepwise regression to select useful variables. We hope to find useful variables and provide more correct infromation in the financial markets. Sentiment indicators are useful in this article.
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Chen, Xiuling, and 陳秀霖. "Predictive Modeling and Analysis for Scores on the General Scholastic Ability Test-A Case Study of a Senior High School in Tainan City." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/qncb9e.
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碩士國立中興大學
應用數學系所
101
Students have two ways to enter their purpose college which are “Admission by selection” and “Entrance examination”, since the Multi-route Promotion Program (MRPP) for College-bound Seniors has been implemented. The way in“Admission by selection” is divide into two parts -Starry recommended and Individual applications. Both of them use the grades of Scholastic Ability Test for appraising through comparison.However,for the impact of low birth rate and the change of policies , many colledge adjust higher ration of students from “Admission by selection”. Waiting Department Required Test in july is quite a long time , most students lose their patience , and they want to decide their ideal college as soon as possible,hence the grades of Scholastic Ability Test becomes more and more important. The study shows that the variables are the data students graduated in 2012 and 2013 years, which are the grades of Scholastic Ability Test, the grades of simulated tests, scores on the Basic Competence Test, GEPT for all primary,average scores in second year at high school, groups,sex,this school or other schools.I analyze the data by using software Excel 2010 and R i3862.15.2, correlation, simple linear regression, multiple linear regression,one-way anova,and gradually fine the best fitted line to predict. The conclusions are as follows: (1)The Predictive model is : ModelA: The Predictive Scores =-6.397+0.258× simulated test 1+0.375× simulated test 2+0.235× simulated test3+0.051×scores on the Basic Competence Test ModelB: The Predictive Scores =-8.807+0.179× simulated test 1+0.286× simulated test 2+0.229× simulated test3+-1.14×groups+0.070×scores on the Basic Competence Test+0.068×average scores in second year at high school (2)The scores on the Basic Competence Test, average scores in second year at high school, the grades of simulated tests influence the grades of Scholastic Ability Test. (3)The scores on the Basic Competence Test influence average scores in second year at high school and the grades of simulated tests. (4)Simulated tests have correlation . (5)Average scores in second year at high school influence the grades of simulated tests. (6)GEPT for all basic level has an influence on English scores in second year at high school,English grades of Scholastic Ability Test and the grades of Scholastic Ability Test. (7)Sex does not influence the grades of Scholastic Ability Test. (8)Graduated from this school or other schools does not influence the grades of simulated tests.
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Mphokane, Adelaide. "The predictive validity of learning potential and English language proficiency for work performance of candidate engineers." Diss., 2014. http://hdl.handle.net/10500/14410.
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The aim of this research was (1) to provide empirical data of learning potential and English language proficiency for work performance; (2) to establish whether race and gender influence work performance; (3) to evaluate practical utility and to propose recommendations for selection purposes. The Learning Potential Computerised Adaptive Test and the English Literacy Skills Assessment were used as measuring instruments to measure learning potential and English language proficiency respectively. Work performance data were obtained from the normal performance data system of the company where the research was conducted. ANOVA results showed differences between race and gender groupings. A regression analysis confirmed the predictive validity of learning potential and English language proficiency on work performance. The Spearman rho correlation coefficient (p < 0.05) showed a significant positive correlation between the investigated variablesIndustrial & Organisational Psychology
M. A. (Industrial & Organisational Psychology)
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Davis, Ryan Jonathan. "The validation of a psychological assessment battery for the selection of customer service agents in a South African commercial airline company." Diss., 2013. http://hdl.handle.net/10500/11969.
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The purpose of the research was to determine whether measures of ability,
personality and behaviour would significantly predict job performance of customer
service agents in a South African commercial airline company. The Verbal
Interpretation Test (VCC1), Numerical Reasoning Test (NP6.1), Basic Checking Test
(CP7.1C), Occupational Personality Questionnaire (OPQ32) and a competency
based interview were completed by job applicants. Customer Contact Competency
(CCC) scores and a Person Job Match (PJM) score were derived from the OPQ32
and ability measures to ensure job relevance during selection assessment. Job
performance statistics in the form of training scores and supervisor ratings (from
performance appraisals and criterion questionnaires) were obtained for the sample
as criterion data. Correlations revealed statistically significant small to moderate
correlations between the predictors and the criterion dataIndustrial & Organisational Psychology
M.Com (Industrial & Organisational Psychology)
Books on the topic "Superior Predictive Ability test"
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Gordon, Edwin. Predictive validity studies of IMMA and ITPT: A two-year longitudinal predictive validity study of the instrument timbre preference test and the intermediate measures of music audiation. Chicago, IL: G.I.A. Publications, 1989.
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Gordon, Edwin. Predictive validity studies of IMMA and ITPT: A two-year longitudinal predictive validity study of the Instrument timbre preference test and the Intermediate measures of music audiation. Chicago, IL: G.I.A. Publications, 1989.
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Pierard, Luc A., and Lauro Cortigiani. Stress echocardiography: diagnostic and prognostic values and specific clinical subsets. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198726012.003.0015.
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Stress echocardiography is a widely used method for assessing coronary artery disease, due to its high diagnostic and prognostic value. While inducible ischaemia predicts an unfavourable outcome, its absence is associated with a low risk of future cardiac events. The method provides superior diagnostic and prognostic information than standard exercise electrocardiography and perfusion myocardial imaging in specific clinical subsets, such as women, hypertensive patients, and patients with left bundle branch block. Stress echocardiography allows effective risk assessment also in the diabetic population. The evaluation of coronary flow reserve of the left anterior descending artery by transthoracic Doppler adds diagnostic and prognostic information to that of standard stress test. Stress echocardiography is indicated in the cases when exercise electrocardiography is unfeasible, uninterpretable or gives ambiguous result, and when ischaemia during the test is frequently a false-positive response, as in hypertensive patients, women, and patients with left ventricular hypertrophy. Viability detection represents another application of stress echocardiography. The documentation of a large amount of viable myocardium predicts improved ejection fraction, reverse remodelling, and improved outcome following revascularization in patients with ischaemic cardiomyopathy. Moreover, stress echocardiography can aid significantly in clinical decision-making in patients with valvular heart disease through dynamic assessment of primary or secondary mitral regurgitation, transvalvular gradients, and pulmonary artery systolic pressure, as well as before vascular surgery due to the excellent negative predictive value. Finally, stress echocardiography allows effective risk stratification in patients with hypertrophic cardiomyopathy through evaluation of inducible ischaemia, coronary flow reserve, and intraventricular gradient.
Book chapters on the topic "Superior Predictive Ability test"
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Netšunajev, Aleksei, Sven Nõmm, Aaro Toomela, Kadri Medijainen, and Pille Taba. "Sentence Writing Test for Parkinson Disease Modeling: Comparing Predictive Ability of Classifiers." In Intelligent Information and Database Systems, 345–57. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-41964-6_30.
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Carstensen, Kai, Klaus Wohlrabe, and Christina Ziegler. "Predictive Ability of Business Cycle Indicators under Test A Case Study for the Euro Area Industrial Production." In Economic Forecasts, edited by Ralf Brüggemann, Winfried Pohlmeier, and Werner Smolny. Berlin, Boston: De Gruyter, 2011. http://dx.doi.org/10.1515/9783110510843-006.
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Taneja, Abhishek. "Enhancing Web Data Mining." In Advances in Data Mining and Database Management, 116–36. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-0613-3.ch005.
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An enormous production of databases in almost every area of human endeavor particularly through web has created a great demand for new, powerful tools for turning data into useful, task-oriented knowledge. The aim of this study is to study the predictive ability of Factor Analysis a web mining technique to prevent voting, averaging, stack generalization, meta- learning and thus saving much of our time in choosing the right technique for right kind of underlying dataset. This chapter compares the three factor based techniques viz. principal component regression (PCR), Generalized Least Square (GLS) Regression, and Maximum Likelihood Regression (MLR) method and explores their predictive ability on theoretical as well as on experimental basis. All the three factor based techniques have been compared using the necessary conditions for forecasting like R-Square, Adjusted R-Square, F-Test, JB (Jarque-Bera) test of normality. This study can be further explored and enhanced using sufficient conditions for forecasting like Theil's Inequality coefficient (TIC), and Janur Quotient (JQ).
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de Souza, Anacleto S., Leonardo G. Ferreira, and Adriano D. Andricopulo. "2D and 3D QSAR Studies on a Series of Antichagasic Fenarimol Derivatives." In Pharmaceutical Sciences, 956–77. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1762-7.ch037.
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Chagas disease is one of the most important neglected tropical diseases. Endemic in Latin America, the disease is a global public health problem, affecting several countries in North America, Europe, Asia and Oceania. The disease affects around 8-10 million people worldwide and the limited treatments available present low efficacy and severe side effects, highlighting the urgent need for new therapeutic options. In this work, the authors developed QSAR models for a series of fenarimol derivatives exhibiting anti-T. cruzi activity. The models were constructed using the Hologram QSAR (HQSAR), Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices Analysis (CoMSIA) methods. The QSAR models presented substantial predictive ability for a series of test set compounds (HQSAR, r2pred = 0.66; CoMFA, r2pred = 0.82; and CoMSIA, r2pred = 0.76), and were valuable to identify key structural features related to the observed trypanocidal activity. The results reported herein are useful for the design of novel derivatives having improved antichagasic properties.
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Mueller, Thomas F., and Valerie Luyckx. "Special considerations in patients undergoing renal replacement therapy and kidney transplant patients." In ESC CardioMed, edited by Christoph Wanner, 1003–6. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198784906.003.0241.
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Cardiovascular disease (CVD) is the leading cause of death in patients with end-stage kidney disease (ESKD) on dialysis, peri-transplant, and after transplantation. The coexistence of traditional cardiovascular risk factors with superimposed renal disease- and transplantation-related risk factors such as uraemia, vascular calcification, inflammation, electrolyte abnormalities, volume shifts, transplant surgery, infections, and immunosuppression makes assessment and treatment more complex when compared with patients without renal disease. For coronary artery disease, evidence suggests less benefit in ESKD and renal transplant patients compared to those with milder renal dysfunction of traditional primary and secondary prevention strategies including angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta blockers, statins, and antiplatelet agents. Prevention of sudden cardiac death is difficult and the use of implantable cardioverter defibrillators in ESKD patients is being investigated. The diagnosis of myocardial ischaemia in patients with ESKD is challenging given the frequent lack of typical symptoms, abnormal baseline electrocardiograms, and the reduced sensitivity of troponin measurements. Screening for CVD in asymptomatic dialysis patients awaiting transplantation is controversial. Non-invasive screening is recommended for those with significant risk factors although the test of choice is unclear. Positive stress-testing is predictive of cardiac events and death and must be investigated with coronary angiography. Once significant coronary artery disease is diagnosed, the optimal choice of revascularization strategy remains unclear. Coronary artery bypass grafting may be superior to angioplasty with stenting in ESKD and transplant patients. Many questions remain unsatisfactorily answered and much research is required to develop optimal strategies to manage CVD in ESKD and kidney transplant patients.
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"Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques." In Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques, edited by Jeffrey A. Falke and Kurt D. Fausch. American Fisheries Society, 2010. http://dx.doi.org/10.47886/9781934874141.ch10.
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<em>Abstract</em>.—Stream fishes carry out their life histories across broad spatial and temporal scales, leading to spatially structured populations. Therefore, incorporating metapopulation dynamics into models of stream fish populations may improve our ability to understand mechanisms regulating them. First, we reviewed empirical research on metapopulation dynamics in the stream fish ecology literature and found 31 papers that used the metapopulation framework. The majority of papers applied no specific metapopulation model, or included space only implicitly. Although parameterization of spatially realistic models is challenging, we suggest that stream fish ecologists should incorporate space into models and recognize that metapopulation types may change across scales. Second, we considered metacommunity theory, which addresses how trade-offs among dispersal, environmental heterogeneity, and biotic interactions structure communities across spatial scales. There are no explicit tests of metacommunity theory using stream fishes to date, so we used data from our research in a Great Plains stream to test the utility of these paradigms. We found that this plains fish metacommunity was structured mainly by spatial factors related to dispersal opportunity and, to a lesser extent, by environmental heterogeneity. Currently, metacommunity models are more heuristic than predictive. Therefore, we propose that future stream fish metacommunity research should focus on developing testable hypotheses that incorporate stream fish life history attributes, and seasonal environmental variability, across spatial scales. This emerging body of research is likely to be valuable not only for basic stream fish ecological research, but also multispecies conservation and management.
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Parsons, Thomas D., and Timothy McMahan. "Virtual Environment Grocery Store." In The Role of Technology in Clinical Neuropsychology. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190234737.003.0013.
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Neuropsychologists are increasingly being asked to determine whether a patient can return to work, classroom, or play (e.g., sports). A difficulty for the neuropsychological assessment of cognitive functioning is that patients’ performance on a cognitive test may have little or no predictive value for how they may perform in a real-world situation (Burgess, Alderman, Evans, Emslie, & Wilson, 1998; Chaytor, Schmitter-Edgecombe, & Burr, 2006). To address this issue, neuropsychologists are increasingly emphasizing the need for tasks that represent real-world functioning and that tap into a number of executive domains (Chaytor & Schmitter-Edgecombe, 2003; Jurado & Rosselli, 2007). Burgess and colleagues (2006) argue that the majority of neuropsychological assessments currently in use today were developed to assess abstract cognitive “constructs” without regard for their ability to predict “functional” behavior. For example, although the construct-driven Wisconsin Card Sorting Test (WCST) is one of the most widely used measures of executive function, it was not originally developed as a measure of executive functioning. Instead, the WCST was preceded by a number of sorting measures that were developed from observations of the effects of brain damage (e.g., Weigl, 1927). While Milner (1963) found that patients with dorsolateral prefrontal lesions had greater difficulty on the WCST than patients with orbitofrontal or nonfrontal lesions, other studies have shown that patients with frontal lobe pathology do not always differ from control subjects on the WCST (Stuss et al., 1983). Some may argue that while there have been some inconsistencies in the literature, data from the construct-driven WCST do appear to provide information relevant to the constructs of set shifting and working memory. However, it can also be argued that the data do not necessarily offer information that would allow a neuropsychologist to predict what situations in everyday life require the abilities that the WCST measures. A number of investigators have argued that performance on traditional tests has little correspondence to everyday activities of daily living. This can leave the neuropsychologist uncertain of the efficacy of the tests for predicting the way in which patients will manage in their everyday lives (Bottari, Dassa, Rainville, & Dutil, 2009; Manchester, Priestly, & Howard, 2004; Sbordone, 2008).
Conference papers on the topic "Superior Predictive Ability test"
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Lee, Gong Hee, Jong Il Park, and Je Hyun Baek. "Performance Assessment of Turbulence Models for the Quantitative Prediction of Tip Leakage Flow in Turbomachines." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53403.
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It is experimentally well-known that high anisotropy of turbulent flow field, which results from the complex shear and rotation effect, is dominant inside tip leakage vortex (TLV). With all this fact, the greater part of the numerical studies to deal with TLV have used an isotropic eddy viscosity model (EVM), and their predictions showed some disagreement with the measurement data. The main objective of the present study is to show the superior ability of the Reynolds stress model (RSM), which can naturally consider the effect of system rotation on turbulence via the rotational production term, over the isotropic EVM for predicting appropriately the complex tip leakage flow in axial type of turbomachines. To achieve this aim, the results obtained from steady-state Reynolds averaged Navier-Stokes simulations based on the Spalart-Allmaras model, Renormalization Group (RNG) k-ε model and RSM are compared with the experimental data for two test configurations: a linear compressor cascade and a forward-swept axial-flow fan. This comparative study of turbulence models suggests that the RSM should be used to predict reasonably the complex tip leakage flow, especially in a rotating environment.
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Lubis, Siti Khodijah, Trie Hartiti Retnowati, and Siti Syawalina. "Predictive Power of Intellectual Ability Test Score on Students’ Fine Art Learning Outcomes." In 3rd International Conference on Arts and Arts Education (ICAAE 2019). Paris, France: Atlantis Press, 2020. http://dx.doi.org/10.2991/assehr.k.200703.009.
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Deppen, Timothy O., Andrew G. Alleyne, Kim A. Stelson, and Jonathan J. Meyer. "Model Predictive Control of an Electro-Hydraulic Powertrain With Energy Storage." In ASME 2011 Dynamic Systems and Control Conference and Bath/ASME Symposium on Fluid Power and Motion Control. ASMEDC, 2011. http://dx.doi.org/10.1115/dscc2011-5969.
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This paper presents a model predictive control approach to solving the energy management problem within a series hydraulic hybrid powertrain. The hydraulic hybrid utilizes a high pressure accumulator for energy storage which has superior power density than conventional battery technology. This makes fluid power attractive for urban driving applications in which there are frequent starts and stops and large startup power demands. Model predictive control was chosen for control design because this technique requires no information about the future drive cycle, which can be highly uncertain in urban settings. The proposed control strategy was validated experimentally using an electro-hydraulic powertrain testbed which includes energy storage. The experimental study demonstrates the controller’s ability to track a reference trajectory while achieving efficient engine operation.
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Freiheit, Theodor. "Validity and Predictive Ability of Wilde’s Cognitive Teamology Model to Design Team Outcomes." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-35257.
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An extensive analysis of the validity of Wilde’s Teamology cognitive diversity model was undertaken with 120 teams composed of over 661 participants. Myers-Briggs Type Indicator (MBTI) data was collected using a qualified test over five years from students enrolled in a fourth year capstone design course. Cognitive factor scores using Wilde’s Teamology model were calculated from the MBTI data for eight factors associated with Wilde’s Information Collection and Decision Making dimensions. Wilde’s team formation model was found to nominally contribute 10.2% to the overall prediction of the variance observed in design team outcomes using a linear regression model with a threshold that the cognitive scores must exceed. Wilde’s Teamology factors of Imagination (“prophetic, guided by inner fantasies and visions”), Community (“expressive, tactful builder of group moral”), and Evaluation (“uses personal values to distinguish good/bad”) were found to be statistically associated to design team outcomes.
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Batta, Nathan, and Daniel Doscher. "Model Predictive Control of Double Stacked Suspension System." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-23569.
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Abstract This study examines implementation of a Model Predictive Controller (MPC) to a new concept in active suspension design. Active and passive components are placed in series to mitigate both high and low frequency disturbance inputs at the tire-road interface. This is modelled using an additional mass spring damper tuned to regulate high frequency inputs, leaving the active components to respond to low frequency inputs. A generic half car model for such a system is developed and subjected to various disturbance inputs at constant velocity and output to verify the system dynamics. Inputs include step, multimodal, and random disturbances as well as a step input that returns to zero. These trials serve as a baseline to evaluate the performance of the passive suspension as well as a Model Predictive Controller. Current research that uses MPC in active suspension design focuses heavily on the traditional half car model with 4 DOF[4]. MPC is applied to this new 6 DOF model and incorporates preview information into the controller response for each of the test cases. The cost function for the MPC places penalties on the translational and rotational position and velocity of the chassis relative to a reference state that is based on each disturbance profile. Parameters of interest are driver absorbed power due to both linear and rotational movement of the chassis. The results for each test case demonstrate the utility of MPC. For every response, there is a decrease in the absorbed power due to rotational and linear sources on the magnitude of 98–100%. The incorporation of preview information also removed the rotation of the chassis for each test case by placing a heavy weight upon its movement. For the step input, the controller reduced the peak rate of change of the chassis by 71.4%. For the multi-mode input, the low frequency sinusoidal inputs showed a dramatic reduction in vertical displacement in the steady state behavior as the MPC will produce an output that is tuned to cancel the disturbance. The high frequency effects are also effectively removed by the passive components of the suspension. This ability to mitigate both sources of disturbance is a marked advantage of the double-stacked suspension design. MPC allowed for the overall reduction of chassis movement by 54.0% with preview information. This improvement is due to the ability of the double stacked suspension with MPC to use the additional degrees of freedom to attenuate disturbances at more than one frequency. The random input demonstrates the ability of the controller to maintain a smooth chassis trajectory even with a chaotic road profile. Finally, the step up-down input demonstrates the ability of the controller to use other components of the suspension system to mitigate a disturbance in order to keep the chassis stable. These results demonstrate that preview information can be used to take full advantage of double stacked, active suspensions and further enhance mobility over different kinds of terrain. Future work includes investigating the effectiveness of other predictive control methods such as two-point boundary value problem or dynamic programming, optimizing the weights used, or adding constraints to the model.
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Roychowdhury, Sushovan, Tomas Månsson, and Thomas Hansson. "Failure Assessment of Test Coupons: Comparison Between Model Predictions and Test Results." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-75734.
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A common requirement for engine structures designed in the aviation industry is the ability to withstand the limit and ultimate loads with a flaw of certain size. Thus, reliable prediction of failure load is of utmost importance. In this paper, predictions from several applicable failure criteria are compared with test results. The tests are carried out on simple coupons with a rectangular cross-section and containing a surface crack. Majority of the tests are carried out under tensile loads and a few under bending loads. The tests correspond to two titanium alloys and two nickel-based super-alloys. The tests span a wide range of temperature (room temp to 700° C), and two forms, namely, cast and forged. In total over 200 test results are obtained and compared with predictions. The predictive models include (i) elasto-plastic J-integral analysis through FEA (ii) Failure Assessment Diagram (R6v3 and SINTAP) (iii) elastic stress intensity factor (LEFM) and (iv) average stress over remaining cross-section. The comparisons demonstrate that the R6v3 FAD method provide a reasonable estimate of the failure load for the test coupon geometry with surface cracks. The average stress approach, though works well for purely tensile loading, cannot cope with bending-dominated loads. On the other hand, predictions from LEFM approach can be non-conservative by up to a factor of two.
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Costarella, Marianna, Lucilla Monteleone, Roberto Steindler, and Stefano Maria Zuccaro. "Physical and Psychical Conditions Decline of Older People With Age, Measured by Functional Reach Test and by Mini Mental State Examination." In ASME 2008 9th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2008. http://dx.doi.org/10.1115/esda2008-59055.
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There are several tests to value the psychophysical characteristics of older people and, among all, the most suitable to this aim are here considered the Functional Reach (FR) test, as an index of the aptitude to maintain balance in upright position, and the Mini Mental State Examination (MMSE), as a global index of cognitive abilities. The sample of older people we have analysed concerns 50 healthy subjects divided into three groups according to the age (15 from 55 to 64 years old, 19 from 65 to 74 years old, and 16 more than 75 years old); they underwent a FR test, which consists first in the measurement of the anthropometric characteristics, then in the execution of the test itself, and finally in the study of the upright posture carried out analysing the Centre of Pressure (COP) trend; they underwent as well a MMSE to value the main areas of the cognitive function concerning the space-temporal orientation, the short-term memory, the attention ability, the calculus ability and the praxis-constructive ability. The results of these tests show, according to the age, a loss both of the physical performances (FR, FR related to height, and COP displacement), and of the cognitive abilities (MMSE); however, in all cases, the only significant changes are those between the first and the other two groups of age. A comparison between the results of male and female subjects inside the three groups, although the results of the males are generally superior to the female ones, is never significant; moreover, the differences of the FR tests, in particular, are completely not significant if compared to the height of the subjects. Finally, a comparison between FR and MMSE shows a quicker decline of the physical performances with regard to the cognitive ones.
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Yang, Bo-Suk, and Yun-Hi Lee. "Artificial Life Algorithm for Function Optimization." In ASME 2000 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/detc2000/dac-14524.
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Abstract This paper presents an enhanced artificial life algorithm for function optimization. As artificial life organisms have a sensing system, they can find the resource they want and metabolize it. The characteristics of artificial life are emergence and dynamic interaction with the environment. In other words, the micro-interaction with each other in the artificial life’s group results in emergent colonization in the whole system. The optimizing ability and convergent characteristics of this proposed algorithm is verified by using three well-known test functions. The numerical results also show that the proposed algorithm is superior to the genetic algorithm and immune genetic algorithm for the multimodal function.
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Zangrilli, Ursula T., and Lisa M. Weiland. "Modeling the Diluent Effect on Streaming Current for Ionic Polymer Transducers in Shear." In ASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/smasis2012-7976.
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Ionic Polymer Transducers (IPTs) are devices that exhibit superior charge sensing capabilities. Further, they can produce an electric signal in any mode of deformation. These sensors can be manufactured with various forms of diluent. Experimental results indicate that both the type and amount of the diluent in the IPT make a difference on the strength of the electrical current output. The streaming potential hypothesis is currently the only way to explain the existence of a electrical current in shear deformation. This work expands on a model previously presented to test the model’s ability to determine the effect of diluent variation and amount of diluent uptake.
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Pourhassan, Alireza, Ahmed A. Gheni, and Mohamed A. ElGawady. "Effect of Aggregate Size on the Retention of Conventional and Rubberized Chip Seal." In IABSE Congress, New York, New York 2019: The Evolving Metropolis. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2019. http://dx.doi.org/10.2749/newyork.2019.2089.
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<p>A common defect of chip seals is chip loss or raveling. The previous studies showed uniform grading of aggregate will enhance the retention ability of the chip seal. Also, it was shown that using crumb rubber as an aggregate will enhance the chip seal behavior including aggregate retention. However, no specific study has been done focusing on the effect of aggregate size for rubber nor natural aggregate. This paper is evaluating the effect of chip size on aggregate retention of both natural and rubber aggregate. Standard and modified Vialit tests, and standard and modified Pennsylvania tests which apply different forms of mechanical energy in different temperature was used to assess the aggregate-binder bond interaction and study the chip seal retention. Test results showed different trends for the effect of size on chip retention under impact load versus dynamic load because of different modes of failure. However, rubber particles showed a superior performance rather than natural aggregate in all cases.</p>