Distance covariance is a measure of dependence between two random variables that take values in two, general different, metric spaces, see Sz\'ekely, Rizzo and Bakirov (2007) Lyons (2013). It known the distance covariance, its generalization $\alpha$-distance can be defined several different ways are equivalent under some moment conditions. The present paper considers four such definitions find...

Abstract The article focuses on estimating effects in nonrandomized studies with two outcome measurement occasions and one predictor variable. Given such a design, the analysis approach can be to include at previous time point as regression model (ANCOVA), or predict change-score of variable (CHANGE). Researchers demonstrated that both approaches result different conclusions regarding reported ...