Girls tend to outperform boys in reading tests, while they usually lag behind boys in math. However, the size of the gender gap varies to a great extent between countries. While the existing literature explains these differences as being mainly due to cultural factors, this paper explores...

This study evaluates the employment impact of disability anti-discrimination laws in OECD countries. The study focuses on the varieties of these domestic laws from an international perspective, particularly the reasonable accommodation duty which is considered a critical factor regarding the...

Misclassification is found in many of the variables used in social sciences and, in practice, tends to be ignored in statistical analyses, and this can lead to biased results. This paper shows how to correct for differential misclassification in multilevel models and illustrates the extent to...

Group-level variance estimates of zero often arise when fitting multilevel or hierarchical linear models, especially when the number of groups is small. For situations where zero variances are implausible a priori, we propose a maximum penalized likelihood approach to avoid such boundary...

An additive multilevel item structure (AMIS) model with random residuals is proposed. The model includes multilevel latent regressions of item discrimination and item difficulty parameters on covariates at both item and item category levels with random residuals at both levels. The AMIS model is...

Reliable access to dependable, high quality childcare services is a vital concern for large numbers of American families. The childcare industry consists of private nonprofit, private for-profit, and governmental providers that differ along many dimensions, including quality, clientele served,...