An appropriate estimate of statistical power is critical for the design of intervention studies. Although the inclusion of a pretest covariate in the test of the primary outcome can increase statistical power, samples selected on the basis of pretest performance may demonstrate range restriction on the selection measure and other correlated…

The Progress in International Reading Literacy Study (PIRLS) is an international assessment of student performance in reading literacy at the fourth grade. PIRLS measures students in the fourth year of formal schooling because this is typically when students' learning transitions from a focus on "learning to read" to a focus on…

Estimation of parameters of random effects models from samples collected via complex multistage designs is considered. One way to reduce estimation bias due to unequal probabilities of selection is to incorporate sampling weights. Many researchers have been proposed various weighting methods (Korn, & Graubard, 2003; Pfeffermann, Skinner,…

This study aimed at investigating grade four students learning at Jimma town, Ethiopia. A cross sectional survey method was employed. Students, teachers and principals were participants of the study. Standardized tests, questionnaire, interview and observation were the instruments used to collect authentic information from the research…

In this article, we consider estimation of parameters of random effects models from samples collected via complex multistage designs. Incorporation of sampling weights is one way to reduce estimation bias due to unequal probabilities of selection. Several weighting methods have been proposed in the literature for estimating the parameters of…

At present, although the percentages of students with disabilities (SDs) and/or students who are English language learners (ELL) excluded from a NAEP administration are reported, no statistical adjustment is made for these excluded students in the calculation of NAEP results. However, the exclusion rates for both SD and ELL students vary…

A multitude of methods has been proposed to estimate the sampling variance of ratio estimates in complex samples (Wolter, 1985). Hansen and Tepping (1985) studied some of those variance estimators and found that a high coefficient of variation (CV) of the denominator of a ratio estimate is indicative of a biased estimate of the standard error of a…

By the spring of 2000, forty states had begun using student test scores to rate school performance. Twenty states have gone a step further and are attaching explicit monetary rewards or sanctions to a school's test performance. In this paper, the authors focus on accountability programs in which states measure the effectiveness of individual…