Migration and stratification are increasingly intertwined. One day soon it will be impossible to understand one without the other. Both focus on life chances. Stratification is about differential life chances - who gets what and why - and migration is about improving life chances - getting more of the good things of life. To examine the interconnections of migration and stratification, we addre...

This paper presents necessary conditions for segregation of the population in multi-community models with housing markets and heterogeneous households. The conditions for the sorting of the population according to income classes or other dimensions of heterogeneity are established without explicitly describing the household utility function and budget constraint. They therefore apply to a broad...

This paper investigates the use of stratified sampling as a variance reduction technique for approximating integrals over large dimensional spaces. The accuracy of this method critically depends on the choice of the space partition, the strata, which should be ideally fitted to the subsets where the functions to integrate is nearly constant, and on the allocation of the number of samples within...

[1] Many lakes show vertical stratification of their water masses, at least for some extended time periods. Density differences in water bodies facilitate an evolution of chemical differences with many consequences for living organisms in lakes. Temperature and dissolved substances contribute to density differences in water. The atmosphere imposes a temperature signal on the lake surface. As a ...

Moore and Pollack have recently given an analysis of R.ST relations in tel'mS of in tent ional versus in format ional levels of discourse [5]. Accol'ding to their (convincing) analysis, presentational RST relations correspond to the intentional level of discourse and subject matter relations to the inlbrmational level. For each text there shouhl exist two RST analyses: one containing only prese...

In this paper, the effect of cationic and anionic ion sizes on the charge storage capability of graphene nanosheets is investigated. The electrochemical properties of the produced electrode are studied using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques in 3M NaCl, NaOH, and KOH electrolytes. Scanning electron microscopy (SEM) is used to characterize the mi...

Recently Zuhair Abdul Ghafoor Al-Johar [12] has directed our attention to a syntactic constraint that is—on the face of it—tighter than NF’s device of stratification; in this little essay I consider a weakening, namely the generalisation of stratification to stratification mod n. So far the coterie of NFistes has considered neither the possibility that the class of unstratified formulæ in the l...

We prove a direct image theorem stating that the direct image of a Galois formula by a morphism of difference schemes is equivalent to a Galois formula modulo the theory ACFA of existentially closed difference fields. As a consequence, we obtain an effective quantifier elimination procedure and a precise algebraic-geometric description of definable sets over existentially closed difference fiel...