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The use of propensity scores in psychological and educational research has been steadily increasing in the last 2 to 3 years. However, there are some common misconceptions about the use of different estimation techniques and conditioning choices in the context of propensity score analysis. In addition, reporting practices for propensity score analyses often(More)
Propensity score analysis is frequently used to reduce the potential bias in estimated effects obtained from observational studies. Appropriate implementation of propensity score adjustments is a multi-step process presenting many alternatives for researchers in terms of estimation and conditioning methods. Further, evaluation of the sample data after(More)
The independent samples t-test is one of the most used tests for detecting true mean differences. The SAS system provides the PROC TTEST procedure which is an easy way to conduct a test for the difference between two population means by assuming homogeneity of variance or avoiding it. However, the t-test and its alternatives (the Satterthwaite's approximate(More)
Two proportions from the same sample of observations or from matched-pair samples are correlated. A number of studies proposed interval estimation for the difference in correlated proportions (e. Considering that confidence intervals (CI) are more informative than point estimates but the CI for the difference in correlated proportions is not readily(More)
The purpose of this study was to examine the performance of modification indices (MIs) in finding correct partial invariance models when testing factorial invariance across groups of interest. In the present study, we examined the two commonly used approaches in this area-namely, nonsequential search and sequential search. Using the nonsequential search(More)
Considering that the absence of measurement error in research is a rare phenomenon and its effects can be dramatic, we examine the impact of measurement error on propensity score (PS) analysis used to minimize selection bias in behavioral and social observational studies. A Monte Carlo study was conducted to explore the effects of measurement error on the(More)
In this study, we report findings on the role of preadoption adversity on long-term clinical-range problems in adopted Chinese girls. Four waves (2005, 2007, 2009 and 2011) of problem behavior data on 1,223 adopted Chinese girls (M = 4.86 years, SD = 2.82 in 2005) were collected from the adoptive mothers with the Child Behavior Checklist (CBCL). At Wave 1(More)
In educational settings, researchers are likely to encounter multilevel data with cross-classified structure. However, due to the lack of familiarity and limitations of statistical software for cross-classified modeling, most researchers adopt less optimal approaches to analyze cross-classified multilevel data in testing measurement invariance. We conducted(More)
The independent means t-test is commonly used for testing the equality of two population means. However, this test is very sensitive to violations of the population normality and homogeneity of variance assumptions. In such situations, Yuen's (1974) trimmed t-test is recommended as a robust alternative. The purpose of this paper is to provide a SAS macro(More)