Is there a relation between trust and trustworthiness?

We provide new evidence about a positive correlation between the own amount sent and the own amount returned in the investment game. Our analysis relies on experimental data collected under the strategy method for establishing our main result. While the percentage returned is independent of the amount received for most of our subjects, it is strongly correlated to their amount sent as a trustor. Our analysis is based on a two-way classification of subjects : according to their trusting type and according to their reciprocal type. We show the existence of a strong correlation between trusting types and reciprocal types within subjects.

SO(3) vortices and disorder in the 2d SU(2) chiral model

We study the correlation function of the 2d SU(2) principal chiral model on the lattice. By rewriting the model in terms of Z(2) degrees of freedom coupled to SO(3) vortices we show that the vortices play a crucial role in disordering the correlations at low temperature. Using a series of exact transformations we prove that, if satisfied, certain inequalities between vortex correlations imply exponential fall-off of the correlation function at arbitrarily low temperatures. We also present some Monte Carlo evidence that these correlation inequalities are indeed satisfied. Our method can be easily translated to the language of 4d SU(2) gauge theory to establish the role of corresponding SO(3) monopoles in maintaining confinement at small couplings.Comment: 13 pages LaTe

Vortices and the SU(3) string tension

We present simulation results comparing the SU(3) heavy quark potential extracted from the full Wilson loop expectation to that extracted from the expectation of the Wilson loop fluctuation solely by elements of Z(3). The two potentials are found to coincide. This agreement is stable under multiple smoothings of the configurations which remove short distance fluctuations, and thus reflects long-distance physics. It strongly indicates that the asymptotic string tension arises from thick center vortices linking with the Wilson loop.Comment: 8 pages, LaTeX file with 6 eps figure

Instanton Effects in Hadron Spectroscopy Revisited

We use an optimised clover action to study spectroscopy on an instanton ensemble reconstructed from smoothed Monte Carlo configurations. Due to the better chirality of the clover action, the artificial configurations show a marked difference from the free field behaviour obtained with the Wilson action. They however still fail to reproduce the physics observed on the smoothed configurations. The presence of freely propagating quark modes is found to be responsible for this.Comment: 3 pages, LaTeX with 4 eps figures, LATTICE99(topology