The logic of organizational markets: thinking through resource partitioning theory

Resource partitioning theory claims that Increasing concentration enhances the life chances of specialist organizations. We systemati- cally think through this theory,specify implicit background assump- tions,sharpen concepts,and rigorously check the theory s logic.As a result,we increase the theory s explanatory power,and claim contrary to received opinion that under certain eneral conditions, resource partitioning and the proliferation of specialists can take place independently of organizational mass and relative size effects, size localized competition,diversifying consumer tastes, increasing number of dimensions of the resource space,and changing niche widths. Our analysis makes furthermore clear that specialist and generalist strategies are asymmetric, and shows that not concentration enhances the life chances of specialists but economies of scale instead.Under the conditions explicated,we argue that if scale economies come to dominate,the number of organizations in the population increases, regardless of the incumbents sizes.

Universality of ac-conduction in anisotropic disordered systems: An effective medium approximation study

Anisotropic disordered system are studied in this work within the random barrier model. In such systems the transition probabilities in different directions have different probability density functions. The frequency-dependent conductivity at low temperatures is obtained using an effective medium approximation. It is shown that the isotropic universal ac-conduction law, $\sigma \ln \sigma=u$, is recovered if properly scaled conductivity ($\sigma$) and frequency ($u$) variables are used.Comment: 5 pages, no figures, final form (with corrected equations

Network diversity and economic development: a comment

Network diversity yields context-dependent benefits that are not yet fully-understood. I elaborate on a recently introduced distinction between tie strength diversity and information source diversity, and explain when, how, and why they matter. The issue whether there are benefits to specialization is thekey

Density results for automorphic forms on Hilbert modular groups

We give density results for automorphic representations of Hilbert modular groups. In particular, we show that there are infinitely many automorphic representations that have a prescribed discrete series factor at some (but not all) real places.Comment: 35 pages, LaTe