Economists typically object to preference-based explanations of human behavior; differences in preferences “explain everything and therefore nothing”. But this argument is only correct assuming that no empirical evidence exists to discipline preference-based explanations. In fact, over the past decade, personality psychologists have produced a robust collection of stylized facts about human pre...

We study a discrete time model of the growth of two species of plankton with competitive and allelopathic effects on each other N1(k + 1) = N1(k)exp{r1(k)− a11(k)N1(k)− a12(k)N2(k) − b1(k)N1(k)N2(k)}, N2(k + 1) = N2(k)exp{r2(k) − a21(k)N1(k) − a22(k) N2(k)− b2(k)N1(k)N2(k)}. A set of sufficient conditions is obtained for the existence of multiple positive periodic solutions for this model. The ...

Let T be an operator-weighted shift whose weights are 2-by-2 matrices. We say that, given > 0, T is in the -canonical form if each weight is an upper triangular matrix (aij), with 0 ≤ a11, a22 ≤ 1 and a12 6= 0 implies a11, a22 < . We generalize this concept to operator-weighted shifts whose weights are n-by-n matrices and we show that every polynomially bounded weighted shift, whose weights are...

How does the structure of the families behind business groups affect the group’s organization, governance, and performance? We construct a unique dataset of family trees and business groups for 93 of the largest business families in Thailand. We find a strong positive association between family size and family involvement in the ownership and control of the family businesses. The founders’ sons...

This paper investigates the relationship between engagement in consulting activities and the research performance of academic scientists. The study relies on a sample of 2678 individual faculty, from five Spanish universities, who have been recipients of publicly funded grants or have been principal investigators in activities contracted by external agents over the period 1999-2004. By implemen...

We produce several families of solutions for two-component nonlinear Schrödinger/GrossPitaevskii equations. These include domain walls and the first example of an antidark or gray soliton in one component, bound to a bright or dark soliton in the other. Most of these solutions are linearly stable in their entire domain of existence. Some of them are relevant to nonlinear optics, and all to Bose...