Impacts of project attributes on investment preferences : an empirical cluster analysis of energy conservation investment attitudes

Investment attitude refers to the way managements of firms value attributes of investmentproposals and weigh them in their final appraisal. It seems that among firms in the Netherlands an investment attitude exists that hinders theimplementation of energy conservation projects. Using paired comparison results from a survey on energy conservation, this paper evaluates investmentpreferences of firms by applying a Bradley-Terry model. The impact of project attributes on the investment preference is analysed in order to disclosethe underlying investment attitude and to identify barriers to the advance of energy conservation technologies. A latent class approach is used todetect clusters of firms for which specific barners play a dominant role

Kondo screening cloud in the single-impurity Anderson model: A density matrix renormalization group study

A magnetic moment in a metal or in a quantum dot is, at low temperatures, screened by the conduction electrons through the mechanism of the Kondo effect. This gives rise to spin-spin correlations between the magnetic moment and the conduction electrons, which can have a substantial spatial extension. We study this phenomenon, the so-called Kondo cloud, by means of the density matrix renormalization group method for the case of the single-impurity Anderson model. We focus on the question whether the Kondo screening length, typically assumed to be proportional to the inverse Kondo temperature, can be extracted from the spin-spin correlations. For several mechanisms -- the gate potential and a magnetic field -- which destroy the Kondo effect, we investigate the behavior of the screening cloud induced by these perturbations.Comment: updated some data, minor change