Unemployment, Market Work and Household Production

Using time-diary data from four countries we show that the unemployed spend most of the time not working for pay in additional leisure and personal maintenance, not in increased household production. There is no relation between unemployment duration and the split of time between household production and leisure. U.S. data for 2003-2006 show that almost none of the lower amount of market work in areas of long-term high unemployment is offset by additional household production. In contrast, in those areas where unemployment has risen cyclically reduced market work is made up almost entirely by additional time spent in household production.unemployment, time use, household production, paid work

Evidence on Unemployment, Market Work and Household Production

Time-diary data from four countries suggest that differences in market time between the unemployed and employed represent additional leisure and personal maintenance rather than increased household production. U.S. data for 2003-2006 show that almost none of the reduction in market work in areas of long-term high unemployment is offset by additional work at home. In contrast, in those areas where unemployment has risen cyclically, reduced market work is largely substituted by additional time in household production.unemployment, time use, household production, paid work

Phase transition and topology in 4d simplicial gravity

We present data indicating that the recent evidence for the phase transition being of first order does not result from a breakdown of the ergodicity of the algorithm. We also present data showing that the thermodynamical limit of the model is independent of topology.Comment: 3 latex pages + 4 ps fig. + espcrc2.sty. Talk presented at LATTICE(gravity

Asymmetric correlation matrices: an analysis of financial data

We analyze the spectral properties of correlation matrices between distinct statistical systems. Such matrices are intrinsically non symmetric, and lend themselves to extend the spectral analyses usually performed on standard Pearson correlation matrices to the realm of complex eigenvalues. We employ some recent random matrix theory results on the average eigenvalue density of this type of matrices to distinguish between noise and non trivial correlation structures, and we focus on financial data as a case study. Namely, we employ daily prices of stocks belonging to the American and British stock exchanges, and look for the emergence of correlations between two such markets in the eigenvalue spectrum of their non symmetric correlation matrix. We find several non trivial results, also when considering time-lagged correlations over short lags, and we corroborate our findings by additionally studying the asymmetric correlation matrix of the principal components of our datasets.Comment: Revised version; 11 pages, 13 figure

Different but Equal: Total Work, Gender and Social Norms in the EU and US Time Use.

Overall, the issue of whether Europeans are lazy or Americans are crazy seems of second-order importance relative to understanding the determinants of individual behavior. Amore useful, scientific approach is to assume that underlying tastes are common to both continents, while technologies, institutions, or interpersonal influences like norms or externalities may differ and evolve differently. The fact that Americans work on weekends or more often at odd hours of the day may simply represent a bad equilibrium that no individual agent can improve upon—and would certainly not wish to deviate from, given what all others are doing. Especially if norms and other externalities are important, one should recognize that the invisible hand may lead agents to places like this.

Different but Equal: Total Work, Gender and Social Norms in EU and US Time Use.

Using time-diary data from 27 countries, we demonstrate a negative relationship between real GDP per capita and the female-male difference in total work time—the sum of work for pay and work at home. We also show that in rich non-Catholic countries on four continents men and women do the same amount of total work on average. Our survey results demonstrate that labor economists, macroeconomists, sociologists and the general public consistently believe that women perform more total work. The facts do not arise from gender differences in the price of time nor from differences in intra-family bargaining: Gender equality is not associated with marital status, and most of the variance in gender total work differences arises from within-couple differences. A theory of social norms could account for within-education group and within-region gender differences being smaller than inter-group differences. It is consistent with cross-national evidence from the World Values Surveys and various sets of microeconomic data.time use;gender differences;household production;paid work;

4d Simplicial Quantum Gravity Interacting with Gauge Matter Fields

The effect of coupling non-compact $U(1)$ gauge fields to four dimensional simplicial quantum gravity is studied using strong coupling expansions and Monte Carlo simulations. For one gauge field the back-reaction of the matter on the geometry is weak. This changes, however, as more matter fields are introduced. For more than two gauge fields the degeneracy of random manifolds into branched polymers does not occur, and the branched polymer phase seems to be replaced by a new phase with a negative string susceptibility exponent $\gamma$ and fractal dimension $d_H \approx 4$.Comment: latex2e, 10 pages incorporating 2 tables and 3 figures (using epsf

Electron dynamics in gold and gold–silver alloy nanoparticles: The influence of a nonequilibrium electron distribution and the size dependence of the electron–phonon relaxation

©1999 American Institute of Physics. The electronic version of this article is the complete one and can be found online at: http://link.aip.org/link/?JCPSA6/111/1255/1DOI: 10.1063/1.479310Electron dynamics in gold nanoparticles with an average diameter between 9 and 48 nm have been studied by femtosecond transient absorption spectroscopy. Following the plasmon bleach recovery after low power excitation indicates that a non-Fermi electron distribution thermalizes by electron–electron relaxation on a time scale of 500 fs to a Fermi distribution. This effect is only observed at low excitation power and when the electron distribution is perturbed by mixing with the intraband transitions within the conduction band (i.e., when the excitation wavelength is 630 or 800 nm). However, exciting the interband transitions at 400 nm does not allow following the early electron thermalization process. Electron thermalization with the lattice of the nanoparticle by electron–phonon interactions occurs within 1.7 ps under these conditions, independent of the excitation wavelength. In agreement with the experiments, simulations of the optical response arising from thermalized and nonthermalized electron distributions show that a non-Fermi electron distribution leads to a less intense bleach of the plasmon absorption. Furthermore, the difference between the response from the two electron distributions is greater for small temperature changes of the electron gas (low excitation powers). No size dependence of the electron thermalization dynamics is observed for gold nanoparticles with diameters between 9 and 48 nm. High-resolution transmission electron microscopy (HRTEM) reveals that these gold nanoparticles possess defect structures. The effect of this on the electron–phonon relaxation processes is discussed. 18 nm gold–silver alloy nanoparticles with a gold mole fraction of 0.8 are compared to 15 nm gold nanoparticles. While mixing silver leads to a blue-shift of the plasmon absorption in the ground-state absorption spectrum, no difference is observed in the femtosecond dynamics of the system

Unemployment, Market Work and Household Production

Using time-diary data from four countries we show that the unemployed spend most of the time not working for pay in additional leisure and personal maintenance, not in increased household production. There is no relation between unemployment duration and the split of time between household production and leisure. U.S. data for 2003-2006 show that almost none of the lower amount of market work in areas of long-term high unemployment is offset by additional household production. In contrast, in those areas where unemployment has risen cyclically reduced market work is made up almost entirely by additional time spent in household production.

Maximal-entropy random walk unifies centrality measures

In this paper analogies between different (dis)similarity matrices are derived. These matrices, which are connected to path enumeration and random walks, are used in community detection methods or in computation of centrality measures for complex networks. The focus is on a number of known centrality measures, which inherit the connections established for similarity matrices. These measures are based on the principal eigenvector of the adjacency matrix, path enumeration, as well as on the stationary state, stochastic matrix or mean first-passage times of a random walk. Particular attention is paid to the maximal-entropy random walk, which serves as a very distinct alternative to the ordinary random walk used in network analysis. The various importance measures, defined both with the use of ordinary random walk and the maximal-entropy random walk, are compared numerically on a set of benchmark graphs. It is shown that groups of centrality measures defined with the two random walks cluster into two separate families. In particular, the group of centralities for the maximal-entropy random walk, connected to the eigenvector centrality and path enumeration, is strongly distinct from all the other measures and produces largely equivalent results.Comment: 7 pages, 2 figure