Children's estimation skills on a bounded and unbounded number line task were assessed in the light of their familiarity with numbers. Kindergartners, first graders, and second graders (N = 120) estimated the position of numbers on a 1--100 number line, marked with either two reference points (i.e., 1 and 10: unbounded condition) or three…

The common way to calculate confidence intervals for item response theory models is to assume that the standardized maximum likelihood estimator for the person parameter [theta] is normally distributed. However, this approximation is often inadequate for short and medium test lengths. As a result, the coverage probabilities fall below the given…

This article proposes an innovative approach to estimating the counterfactual without the necessity of generating information from either a control group or a before-measure. Building on the idea that program participants are capable of estimating the hypothetical state they would be in had they not participated, the basics of the Roy-Rubin model…