Abstract. In randomized controlled trials (RCTs), a common strategy to increase power to detect a treatment effect is adjustment for baseline covariates. However, adjustment with partly missing covariates, where complete cases are only ...

Abstract. Researchers in the social and behavioral sciences often have clear expectations about the order and/or the sign of the parameters in their statistical model. For example, a researcher might expect that regression coefficient β₁ ...

Abstract. In this paper a profile analysis that utilizes principal component analysis (PCA) is introduced. Although PCA is popular for a dimension reduction method, it is not well known that unrotated components algebraically are summative ...