Poverty in India during the1990s - a regional perspective

The authors provide estimates of poverty at the regional level in India, spanning the 1990s. Such estimates have not been previously available due to concerns regarding non-comparability of the 1993-94 and 1999-2000 National Sample Survey Organization (NSSO) household survey data. They implement an adjustment procedure to restore comparability based on a methodology developed by Elbers and others (2003). The results indicate a less rapid decline of poverty, at the all-India level than has been suggested by Deaton and Dre (2002), based on a related adjustment methodology. The authors attempt to uncover the source of disagreement across these procedures, by probing a number of their underlying assumptions.Health Economics&Finance,Environmental Economics&Policies,Health Monitoring&Evaluation,Poverty Reduction Strategies,Public Health Promotion,Environmental Economics&Policies,Poverty Assessment,Achieving Shared Growth,Poverty Reduction Strategies,Urban Partnerships&Poverty

Weighted sums of orthogonal polynomials with positive zeros

We study the two sequences of polynomials which arise as denominators of the approximants of even and odd order, respectively, of a Stieltjes fraction, and which may be defined alternatively as a sequence of orthogonal polynomials with positive zeros and the associated sequence of kernel polynomials. Motivated by problems in the setting of birth-death processes, where these sequences play a major role, we focus on the asymptotic behaviour of the sequences and establish convergence of certain weighted sums of the polynomials at hand

Emergence of self-similarity in football dynamics

The multiplayer dynamics of a football game is analyzed to unveil self-similarities in the time evolution of player and ball positioning. Temporal fluctuations in both the team-turf boundary and the ball location are uncovered to follow the rules of fractional Brownian motion with a Hurst exponent of H=0.7. The persistence time below which self-similarity holds is found to be several tens of seconds, implying a characteristic time scale that governs far-from-equilibrium motion on a playing field.Comment: Figures 1 and 2 are blurred due to file-size restriction. Sharply-defined images can be viewed in the final version published by European Physical Journal

Limiting conditional distributions for birth-death processes

In a recent paper one of us identified all of the quasi-stationary distributions for a non-explosive, evanescent birth-death process for which absorption is certain, and established conditions for the existence of the corresponding limiting conditional distributions. Our purpose is to extend these results in a number of directions. We shall consider separately two cases depending on whether or not the process is evanescent. In the former case we shall relax the condition that absorption is certain. Furthermore, we shall allow for the possibility that the minimal process might be explosive, so that the transition rates alone will not necessarily determine the birth-death process uniquely. Although we shall be concerned mainly with the minimal process, our most general results hold for any birth-death process whose transition probabilities satisfy both the backward and the forward Kolmogorov differential equations

Decline and repair, and covariate effects

The failure processes of repairable systems may be impacted by operational and environmental stress factors. To accommodate such factors, reliability can be modelled using a multiplicative intensity function. In the proportional intensity model, the failure intensity is the product of the failure intensity function of the baseline system that quantifies intrinsic factors and a function of covariates that quantify extrinsic factors. The existing literature has extensively studied the failure processes of repairable systems using general repair concepts such as age-reduction when no covariate effects are considered. This paper investigates different approaches for modelling the failure and repair process of repairable systems in the presence of time-dependent covariates. We derive statistical properties of the failure processes for such systems