Statistical Analysis of Humanities and Social Sciences Collaboration Research in China

With the development of humanities and social sciences, research collaboration becomes more and more important. This article studies collaboration phenomena of seventeen kinds of journals’ from 1995-2004 in china. According to statistical data, some characteristics are disclosed, and some tested explanations are given. This article makes a comparison of research collaboration between China and other country, and some differences are studied. A lot of differences of research collaboration among humanities sciences, social sciences and natural sciences are also pointed out

Asymptotic coverage probabilities of bootstrap percentile confidence intervals for constrained parameters

The asymptotic behaviour of the commonly used bootstrap percentile confidence interval is investigated when the parameters are subject to linear inequality constraints. We concentrate on the important one- and two-sample problems with data generated from general parametric distributions in the natural exponential family. The focus of this paper is on quantifying the coverage probabilities of the parametric bootstrap percentile confidence intervals, in particular their limiting behaviour near boundaries. We propose a local asymptotic framework to study this subtle coverage behaviour. Under this framework, we discover that when the true parameters are on, or close to, the restriction boundary, the asymptotic coverage probabilities can always exceed the nominal level in the one-sample case; however, they can be, remarkably, both under and over the nominal level in the two-sample case. Using illustrative examples, we show that the results provide theoretical justification and guidance on applying the bootstrap percentile method to constrained inference problems.Comment: 22 pages, 6 figure

The reaction of consumer spending and debt to tax rebates – evidence from consumer credit data

We use a new panel dataset of credit card accounts to analyze how consumer responded to the 2001 Federal income tax rebates. We estimate the monthly response of credit card payments, spending, and debt, exploiting the unique, randomized timing of the rebate disbursement. We find that, on average, consumers initially saved some of the rebate, by increasing their credit card payments and thereby paying down debt. But soon afterwards their spending increased, counter to the canonical Permanent-Income model. Spending rose most for consumers who were initially most likely to be liquidity constrained, whereas debt declined most (so saving rose most) for unconstrained consumers. More generally, the results suggest that there can be important dynamics in consumers’ response to “lumpy” increases in income like tax rebates, working in part through balance sheet (liquidity) mechanisms