BayesProject: Fast computation of a projection direction for multivariate changepoint detection

Statistics and Computing - This article focuses on the challenging problem of efficiently detecting changes in mean within multivariate data sequences. Multivariate changepoints can be detected by...     

Implementing Monte Carlo tests with p-value buckets

Software packages usually report the results of statistical tests using p-values. Users often interpret these values by comparing them with standard thresholds, for example, 0.1, 1, and 5%, which is sometimes reinforced by a star rating (***, **, and *, respectively). We consider an arbitrary statistical test whose p-value p is not available explicitly, but can be approximated by Monte Carlo samples, for example, by bootstrap or permutation tests. The standard implementation of such tests usually draws a fixed number of samples to approximate p. However, the probability that the exact and the approximated p-value lie on different sides of a threshold (the resampling risk) can be high, particularly for p-values close to a threshold. We present a method to overcome this. We consider a finite set of user-specified intervals that cover [0, 1] and that can be overlapping. We call these p-value buckets. We present algorithms that, with arbitrarily high probability, return a p-value bucket containing p. We prove that for both a bounded resampling risk and a finite runtime, overlapping buckets need to be employed, and that our methods both bound the resampling risk and guarantee a finite runtime for such overlapping buckets. To interpret decisions with overlapping buckets, we propose an extension of the star rating system. We demonstrate that our methods are suitable for use in standard software, including for low p-value thresholds occurring in multiple testing settings, and that they can be computationally more efficient than standard implementations.     

我国农村公共产品的自愿供给:一个博弈分析的框架

本文在相关文献的基础上,采用完全信息静态博弈模型分析研究了农村公共产品的供给问题.模型分析表明,在农村公共产品的供给决策过程中,纳什均衡解是可以达到的,但它小于帕累托最优解.本文还得出了有关农村公共产品供给的几个定理.     

Public Support for Rehabilitation Programs: The Analysis of U.S. Disability Policy

Although political scientists have displayed relatively little interest in research on disability thus far, a brief review of major issues in rehabilitation in the United States indicates the contribution that policy analysts can make to the study of this subject. This opportunity is enhanced by a recent shift in the definition of disability from a medical orientation, which emphasizes functional impairments, and from an economic approach, which stresses vocational limitations, to a socio-political perspective, which regards disability as the product of interactions between individuals and the environment. The latter definition has become the foundation for a new 'minority-group' model of disability that is challenging the traditional 'functional-limitations' paradigm and that might profitably be utilized in future research.     

The Politics of Physical Differences: Disability and Discrimination

Although a "minority-group" model has emerged to challenge the traditional dominance of the "functional-limitations" paradigm for the study of disability, research on attitudes toward disabled people has not produced a theoretical orientation that reflects these developments. This paper proposes a new conceptual framework, based on the fundamental values of personal appearance and individual autonomy, for assessing the "aesthetic" and "existential" anxiety aroused by persons with disabilities. Investigations using this perspective might contribute to determining the attitudinal foundations of the competing models that are dividing research on disability.     

中国新文学发生语境的吊诡——从胡适“他们”与“我们”的白话两难心态出发

作为五四白话文运动的领军人物,胡适在白话为"他们"还是为"我们"自己写作的意识上有着十分尴尬的解说。分析胡适的心理深层症结,对其构建的以白话文为底色的新文学逻辑进行深入梳理,由此我们可以窥见"新青年派"知识群体在现代性演进过程中思想谱系的吊诡。胡适主导的精英意识和另一种启蒙路径——民粹思想形成了鲜明对比。归根结底,无论胡适们当年怎样为"他们"呐喊,他都会走向"我们"。     

Standard Errors for Elasticities: A Comparison of Bootstrap and Asymptotic Standard Errors

This article compares two methods of deriving standard errors for elasticities in a linear expenditure demand system with first-order autoregressive errors. The first is the ordinary Taylor series method and the second is Efron's bootstrap. In an example problem, these two methods yielded similar values for the standard errors, with the exception of the income elasticity standard errors, for which the asymptotic standard errors were apparently too large by a factor of two.     

Existence of Maximum Likelihood Estimates for Multi-dimensional Exponential Families

This paper deals with the existence of maximum likelihood estimators for multi-dimensional exponential families, including curved exponential families. It first gives an algorithm for determining the MLE from the data. Then it establishes that when the parameter set is either open or relatively closed in the natural parameter set, the MLE of the parameter exists in the sense of Hoffmann-Jorgensen.