The automorphism group of a graphon

We study the automorphism group of graphons (graph limits). We prove that after an appropriate "standardization" of the graphon, the automorphism group is compact. Furthermore, we characterize the orbits of the automorphism group on $k$-tuples of points. Among applications we study the graph algebras defined by finite rank graphons and the space of node-transitive graphons.Comment: 29 pages, 2 figure

Tight bounds on the convergence rate of generalized ratio consensus algorithms

The problems discussed in this paper are motivated by general ratio consensus algorithms, introduced by Kempe, Dobra, and Gehrke (2003) in a simple form as the push-sum algorithm, later extended by B\'en\'ezit et al. (2010) under the name weighted gossip algorithm. We consider a communication protocol described by a strictly stationary, ergodic, sequentially primitive sequence of non-negative matrices, applied iteratively to a pair of fixed initial vectors, the components of which are called values and weights defined at the nodes of a network. The subject of ratio consensus problems is to study the asymptotic properties of ratios of values and weights at each node, expecting convergence to the same limit for all nodes. The main results of the paper provide upper bounds for the rate of the almost sure exponential convergence in terms of the spectral gap associated with the given sequence of random matrices. It will be shown that these upper bounds are sharp. Our results complement previous results of Picci and Taylor (2013) and Iutzeler, Ciblat and Hachem (2013)

Equilibrium Exchange Rates in Central and Eastern Europe: A Meta-Regression Analysis

This paper analyses the ever-growing literature on equilibrium exchange rates in the new EU member states of Central and Eastern Europe in a quantitative manner using meta-regression analysis. The results indicate that the real misalignments reported in the literature are systematically influenced, inter alia, by the underlying theoretical concepts (Balassa-Samuelson effect, Behavioural Equilibrium Exchange Rate, Fundamental Equilibrium Exchange Rate) and by the econometric estimation methods. The important implication of these findings is that a systematic analysis is needed in terms of both alternative economic and econometric specifications to assess equilibrium exchange rates.http://deepblue.lib.umich.edu/bitstream/2027.42/40155/3/wp769.pd

Equilibrium exchange rates in Central and Eastern Europe: A meta-regression analysis

This paper analyses the ever-growing literature on equilibrium exchange rates in the new EU member states of Central and Eastern Europe in a quantitative manner using meta-regression analysis. The results indicate that the real misalignments reported in the literature are systematically influenced, inter alia, by the underlying theoretical concepts (Balassa-Samuelson effect, Behavioural Equilibrium Exchange Rate, Fundamental Equilibrium Exchange Rate) and by the econometric estimation methods. The important implication of these findings is that a systematic analysis is needed in terms of both alternative economic and econometric specifications to assess equilibrium exchange rates.equilibrium exchange rate; Balassa-Samuelson effect; meta-analysis

Equilibrium Exchange Rates in Central and Eastern Europe: A Meta-Regression Analysis

This paper analyses the ever-growing literature on equilibrium exchange rates in the new EU member states of Central and Eastern Europe in a quantitative manner using meta-regression analysis. The results indicate that the real misalignments reported in the literature are systematically influenced, inter alia, by the underlying theoretical concepts (Balassa-Samuelson effect, Behavioural Equilibrium Exchange Rate, Fundamental Equilibrium Exchange Rate) and by the econometric estimation methods. The important implication of these findings is that a systematic analysis is needed in terms of both alternative economic and econometric specifications to assess equilibrium exchange rates.equilibrium exchange rate, Balassa-Samuelson effect, meta-analysis