Correlational Meta-Analysis: Independent and Nonindependent Cases
Autor: | Patricia B. Elmore, Susan M. Tracz, John T. Pohlmann |
---|---|
Rok vydání: | 1992 |
Předmět: |
Correlation coefficient
Estimation theory Applied Mathematics 05 social sciences Monte Carlo method 050401 social sciences methods 050301 education Standard score Education Correlation 0504 sociology Sample size determination Meta-analysis Statistics Developmental and Educational Psychology Econometrics 0503 education Applied Psychology Independence (probability theory) Mathematics |
Zdroj: | Educational and Psychological Measurement. 52:879-888 |
ISSN: | 1552-3888 0013-1644 |
DOI: | 10.1177/0013164492052004007 |
Popis: | The purpose of this study was to determine the effect of the violation of the assumption of independence when combining correlation coefficients in a meta-analysis. In this Monte Carlo simulation the following four parameters were used with the values specified: N-the sample size within a study (20, 50, 100), p-the number of predictors (1, 2, 3, 5), rho( i)-the population intercorrelation among predictors (0, .3, .7), rho( p)-the population correlation between predictors and criterion (0, .3, .7). When cnly one predictor was used or when the intercorrelation among predictors equaled zero, the assumption of independence was not violated. The assumption of independence was violated when more than one predictor with an intercorrelation exceeding zero were used. Therefore, rho( i) the index of nonindependence was the main parameter of interest. For both r's and Fisher's z's, the means, medians, and standard deviations showed no discernible change over levels of rho( i) or p, but the precision of estimation of the expected values improved as N increased. The 90%, 95%, and 99% confidence intervals for both r's and Fisher's z's showed no change over levels of rho( i) or p, but the intervals narrowed as N increased. |
Databáze: | OpenAIRE |
Externí odkaz: |