Math achievement is affected by social factors such as socioeconomic status (SES) and domain-general cognitive factors such as phonological ability. Little is known how the effects of cognitive factors change depending on social factors during development. This study focuses on the estimation of...

The evolution of trustworthiness as a major aspect of business ethics depends crucially on whether it can be signaled. If this is impossible, only opportunistic traders will survive. Whereas previous studies have analysed detection agencies (Güth and Kliemt, 1994 and 1998) or have substituted...

Empirical studies analyzing the determinants of U.S. presidential popularity have delivered quite inconclusive results concerning the role of economic variables by assuming linear relationships. We employ penalized spline smoothing in the context of semi-parametric additive mixed models and...

A mathematical model for the hit phenomenon in entertainment within a society is presented as a stochastic process of interactions of human dynamics. The calculations for the Japanese motion picture market based on to the mathematical model agree very well with the actual residue distribution in...

Empirical studies analyzing the determinants of U.S. presidential popularity have delivered quite inconclusive results concerning the role of economic variables by assuming linear relationships. We employ penalized spline smoothing in the context of semi-parametric additive mixed models and...