Log-Poisson statistics and full aging in glassy systems

We argue that Poisson statistics in logarithmic time provides an idealized description of non-equilibrium configurational rearrangements in aging glassy systems. The description puts stringent requirements on the geometry of the metastable attractors visited at age $t_w$. Analytical implications for the residence time distributions as a function of $t_w$ and the correlation functions are derived. These are verified by extensive numerical studies of short range Ising spin glasses.Comment: v3 (final): 8 pages, 4 figures. Minor change

Bounds on the Coefficients of Tension and Flow Polynomials

The goal of this article is to obtain bounds on the coefficients of modular and integral flow and tension polynomials of graphs. To this end we make use of the fact that these polynomials can be realized as Ehrhart polynomials of inside-out polytopes. Inside-out polytopes come with an associated relative polytopal complex and, for a wide class of inside-out polytopes, we show that this complex has a convex ear decomposition. This leads to the desired bounds on the coefficients of these polynomials.Comment: 16 page

Incentive distortions in decentralized systems of governance – why is financing decentralized systems so difficult?

National governments often choose to delegate tasks and burdens to lower levels in a comprehensive system of administration. Local and regional governance thereby becomes an important factor in policy implementation. This paper focuses on the incentive problem that follows from such a delegation of competences to collect taxes and do lending at the local level in a multi-level geo-administrative system. The paper uses the Danish administrative system to illustrate the actual outcomes from such incentive problems. A two-step estimation procedure will be used to derive results on the importance of incentive problems in multi-level geo-administrative systems. Setting up elaborate administrative systems will introduce agency problems that lead to inefficiencies in both local and national governance.