A quantile regression perspective on external preference mapping

AStA Advances in Statistical Analysis - External preference mapping is widely used in marketing and R&D divisions to understand the consumer behaviour. The most common preference map is...     

Exiting TANF: Individual and Local Factors and Their Differential Influence Across Racial Groups*

Objective. We ask whether individual and local factors known to influence reliance on welfare continue to be important under the TANF program, and if such factors differentially affect exit from TANF for African Americans and whites. Methods. We use monthly administrative data on TANF recipients from October 1996 to July 2004 from the Mississippi Department of Human Services. These data are linked to local economic, social, and spatial characteristics to estimate discrete time hazard models of TANF exit. Results. Personal barriers to work (e.g., low education and children) and limited economic and social opportunities in communities reduce the likelihood of leaving TANF. The results show that African‐American exits from TANF are more influenced by human capital and local economic, social, and spatial conditions than are whites' TANF exits. Conclusion. The work‐first initiative under TANF is most viable where individual barriers to work are limited and economic opportunities and community support to become self‐sufficient exist for all people.     

The use of different data sources in the analysis of co-authorship networks and scientific performance

Scientific collaboration is usually derived from archival co-authorship data. Several data sources may be examined, but they all have advantages and disadvantages, especially when a specific discipline or community is of interest. The aim of this paper is to explore the effect of the use of three data sources – Web of Science, Current Index to Statistics and nationally funded research projects – on the analysis of co-authorship networks among Italian academic statisticians. Results provide evidence of our hypotheses on distinct collaboration patterns among statisticians, as well as distinct effects of scientist network positions on scientific performance, by both Statistics subfield and data source.     

Measuring Citizen Satisfaction with Aspects of Public Services from a Local Authority and Determining Their Importance: A Case Study

The measurement of service quality is a theme of great importance to service providers, particularly public agencies. Over the years their role has been changing by providing more and more high quality services, away from basic ones. In this paper the service quality of a local government is analyzed through the measurement of customer satisfaction. The analysis, based on a questionnaire survey, identified and classified the most essential factors that make up the customer satisfaction with the services provided by the Demographic Department of Gioia del Colle, a town in southern Italy.

BUNDLING ELECTRONIC JOURNALS AND COMPETITION AMONG PUBLISHERS

Site licensing of electronic journals has revolutionized the way academic information is distributed. However, many librarians are concerned about the possibility that commercial publishers might abuse site licensing by the practice of bundling. In this paper, we analyze how bundling affects journal pricing in the market of scientific, technical, and medical electronic journals and offer a novel insight on the bundling of a large number of information goods. We find that (i) when bundling is prohibited, surprisingly, industry concentration does not affect prices; (ii) when bundling is allowed, each publisher finds bundling profitable and bundling increases industry profits while reducing social welfare; and (iii) any merger among publishers already active in the market is profitable but reduces social welfare. (JEL: D4, K21, L41, L82)     

Sociology of Terrorism and Counterterrorism: A Social Science Understanding of Terrorist Threat

The purpose of this article is to outline a social science understanding of terrorist threat, with special reference to political violence of new terrorist groups, fundamentalist movements and extremist organisations such as Al-Qaeda. Four main terrorism topics will be examined: (i) Definition of terrorism . We will make explicit the political and moral implications of the word 'terrorism' by tracing a brief history of terrorism; at the same time, a definition of terrorism will be proposed based on an overview of terrorism studies. (ii) Typology of terrorism . The topic to be addressed here concerns the classification of terrorist groups, paying special attention to contemporary fundamentalist movements and extremist organisations (particularly after World War II). (iii) Explanation of terrorism. Criticism will be made of psychological explanations of terrorism that try to trace political violence back to specific personal traits or psychopathological profiles of terrorists. We will offer an alternative explanation, focusing on specific social, cultural and religious factors to be considered the root causes of terrorism. Suicide terrorism will be used as a case study. (iv) C ounterterrorism policy . Here, we will discuss some of the limitations and counterproductive effects of the counterterrorism measures adopted by governments after 9/11, including new antiterrorism legislation, the case of special detention at Guantanamo Bay, and the Iraq invasion. Most of such limitations are due to a misunderstanding of the political culture and ideology of Islamic extremism and fundamentalism (Islamism). Some concluding remarks will summarise the findings of the article and underline the most important suggestions for a future research agenda in the sociology of terrorism and counterterrorism.     

Goodness-of-Fit Testing for the Newcomb-Benford Law With Application to the Detection of Customs Fraud

The Newcomb-Benford law for digit sequences has recently attracted interest in antifraud analysis. However, most of its applications rely either on diagnostic checks of the data, or on informal decision rules. We suggest a new way of testing the Newcomb-Benford law that turns out to be particularly attractive for the detection of frauds in customs data collected from international trade. Our approach has two major advantages. The first one is that we control the rate of false rejections at each stage of the procedure, as required in antifraud applications. The second improvement is that our testing procedure leads to exact significance levels and does not rely on large-sample approximations. Another contribution of our work is the derivation of a simple expression for the digit distribution when the Newcomb-Benford law is violated, and a bound for a chi-squared type of distance between the actual digit distribution and the Newcomb-Benford one.     

Maximum likelihood estimation of ARFIMA models with a Box-Cox transformation

In this paper we study the interaction between the estimation of the fractional differencing parameter d of ARFIMA models and the common practice of instantaneous transformation of the observed time series. At this aim, we first discuss the effect of a nonlinear transformation of the data on the identification of the process and on the estimate of d. Thus, we propose a joint estimation of the Box-Cox parameter and d by means of a modified normalized version of the Whittle likelihood. Then, the variance and covariance matrix of the parameters estimates is obtained. Finally, a Monte Carlo study is performed in order to check the behaviour of the proposed estimators in finite samples.The paper is the result of a joint research of the two authors. As far as it concerns this version of the work, A. DElia wrote Sects. 2, 3, 4, while D. Piccolo wrote Sects. 1, 5, 6.