Rare region effects at classical, quantum, and non-equilibrium phase transitions

Rare regions, i.e., rare large spatial disorder fluctuations, can dramatically change the properties of a phase transition in a quenched disordered system. In generic classical equilibrium systems, they lead to an essential singularity, the so-called Griffiths singularity, of the free energy in the vicinity of the phase transition. Stronger effects can be observed at zero-temperature quantum phase transitions, at nonequilibrium phase transitions, and in systems with correlated disorder. In some cases, rare regions can actually completely destroy the sharp phase transition by smearing. This topical review presents a unifying framework for rare region effects at weakly disordered classical, quantum, and nonequilibrium phase transitions based on the effective dimensionality of the rare regions. Explicit examples include disordered classical Ising and Heisenberg models, insulating and metallic random quantum magnets, and the disordered contact process.Comment: Topical review, 68 pages, 14 figures, final version as publishe

Where do firms manage earnings?

Despite decades of research on how, why, and when companies manage earnings, there is a paucity of evidence about the geographic location of earnings management within multinational firms. In this study, we examine where companies manage earnings using a sample of 2,067 U.S. multinational firms from 1994 to 2009. We predict and find that firms with extensive foreign operations in weak rule of law countries have more foreign earnings management than companies with subsidiaries in locations where the rule of law is strong. We also find some evidence that profitable firms with extensive tax haven subsidiaries manage earnings more than other firms and that the earnings management is concentrated in foreign income. Apart from these results, we find that most earnings management takes place in domestic income, not foreign income.Arthur Andersen (Firm) (Arthur Andersen Faculty Fund

Us knows us in the UK: On director networks and CEO compensation

We analyze the relation between CEO compensation and networks of executive and non-executive directors for all listed UK companies over the period 1996-2007. We examine whether networks are built for reasons of information gathering or for the accumulation of managerial influence. Both indirect networks (enabling directors to collect information) and direct networks (leading to more managerial influence) enable the CEO to obtain higher compensation. Direct networks can harm the efficiency of the remuneration contracting in the sense that the performance sensitivity of compensation is then lower. We find that in companies with strong networks and hence busy boards the directors' monitoring effectiveness is reduced which leads to higher and less performance-sensitive CEO compensation. Our results suggest that it is important to have the 'right' type of network: some networks enable a firm to access valuable information whereas others can lead to strong managerial influence that may come at the detriment of the firm and its shareholders. We confirm that there are marked conflicts of interest when a CEO increases his influence by being a member of board committees (such as the remuneration committee) as we observe that his or her compensation is then significantly higher. We also find that hiring remuneration consultants with sizeable client networks also leads to higher CEO compensation especially for larger firms. © 2011 Elsevier B.V