Almost all social choice rules are highly manipulable,but a few aren't

Explores, for several classes of social choice rules, the distribution of the number of profiles at which a rule can be strategically manipulated. In this paper, we will do comparative social choice, looking for information about how social choice rules compare in their vulnerability to strategic misrepresentation of preferences.I am indebted to Universidad Internacional Menendez Pelayo for an invitation to present an early version of this paper at a June, 1989 conference at Valencia, Spain. Thanks for comments go to the participants of that conference, especially Salvador Barbera; also for comments at seminars at Syracuse University and the University of Rochester.     

Testing for Causal Effects in a Generalized Regression Model With Endogenous Regressors

A unifying framework to test for causal effects in nonlinear models is proposed. We consider a generalized linear‐index regression model with endogenous regressors and no parametric assumptions on the error disturbances. To test the significance of the effect of an endogenous regressor, we propose a statistic that is a kernel‐weighted version of the rank correlation statistic (tau) of Kendall (1938). The semiparametric model encompasses previous cases considered in the literature (continuous endogenous regressors (Blundell and Powell (2003)) and a single binary endogenous regressor (Vytlacil and Yildiz (2007))), but the testing approach is the first to allow for (i) multiple discrete endogenous regressors, (ii) endogenous regressors that are neither discrete nor continuous (e.g., a censored variable), and (iii) an arbitrary “mix” of endogenous regressors (e.g., one binary regressor and one continuous regressor).     

Using geotagged tweets to track population movements to and from Puerto Rico after Hurricane Maria

Population and Environment - After a disaster, there is an urgent need for information on population mobility. Our analysis examines the suitability of Twitter data for measuring post-disaster...     

The Impact of Forecast Errors on Early Order Commitment in a Supply Chain*

Supply chain partnership involves mutual commitments among participating firms. One example is early order commitment, wherein a retailer commits to purchase a fixed‐order quantity and delivery time from a supplier before the real need takes place. This paper explores the value of practicing early order commitment in the supply chain. We investigate the complex interactions between early order commitment and forecast errors by simulating a supply chain with one capacitated supplier and multiple retailers under demand uncertainty. We found that practicing early order commitment can generate significant savings in the supply chain, but the benefits are only valid within a range of order commitment periods. Different components of forecast errors have different cost implications to the supplier and the retailers. The presence of trend in the demand increases the total supply chain cost, but makes early order commitment more appealing. The more retailers sharing the same supplier, the more valuable for the supply chain to practice early order commitment. Except in cases where little capacity cushion is available, our findings are relatively consistent in the environments where cost structure, number of retailers, capacity utilization, and capacity policy are varied.     

Order Progress Information: Improved Dynamic Emergency Ordering Policies

Technologies such as radio‐frequency identification and global positioning systems can provide improved real‐time tracking information for products and replenishment orders along the supply chain. We call this type of visibility order progress information. In this paper, we investigate how order progress information can be used to improve inventory replenishment decisions. To this end, we examine a retailer facing a stochastic lead time for order fulfillment. We characterize a replenishment policy that is based on the classical (Q, R) policy and that allows for releasing emergency orders in response to the order progress information. We show that the optimal structure of this policy is given by a sequence of threshold values dependent on order progress information. In a numerical study we evaluate the cost savings due to this improved replenishment policy.     

Sex after divorce: older adult women’s reflections

People who divorce experience a number of negative impacts, and yet divorce also offers opportunities for growth and transformation. This qualitative study of older adult women offers the possibility that divorce may be sexually empowering, especially for women, based on in-depth interviewing of women who had gone through one or more divorces. Detailed examples of the experiences of fourteen women with divorce and sexual expression are offered, focusing on in which situations divorce might be empowering and how it could contribute to sexual exploration and satisfaction. Overall, for the fourteen women in the study who had experienced divorce, the quality of sex in the marriage impacted the quality of sexual expression after the divorce. Also, these findings supported the idea of transformational learning through divorce, and expand divorce-stress-adjustment and transformational learning perspectives to apply more specifically to sexual expression. Understanding possible impacts of divorce over the lifespan, including strengths-based aspects, is important for social workers as the population they serve ages.     

Defining the Professional Foundation in Social Work Education

Abstract

This paper reports the results of a national study designed to identify preferred curriculum content important to the “professional foundation” in social work education. All BSW program directors were surveyed, using the Delphi Technique, to evaluate potential curriculum content The heavy response indicated a strong interest in this timely issue. The authors found that there is a high degree of consensus on curriculum material thought to be appropriate for a professional foundation.     

The quality and use of regulatory analysis in 2008

This article assesses the quality and apparent use of regulatory analysis for economically significant regulations proposed by federal agencies in 2008. A nine-member research team used a six-point (0-5) scale to evaluate regulatory analyses according to criteria drawn from Executive Order 12866 and Office of Management and Budget Circular A-4. Principal findings include: (1) the average quality of regulatory analysis, though not high, is somewhat better than previous regulatory scorecards have shown; (2) quality varies widely; (3) biggest strengths are accessibility and clarity; (4) biggest weaknesses are analysis of the systemic problem and retrospective analysis; (5) budget or "transfer" regulations usually receive low-quality analysis; (6) a minority of the regulations contain evidence that the agency used the analysis in significant decisions; (7) quality of analysis is positively correlated with the apparent use of the analysis in regulatory decisions; and (8) greater diffusion of best practices could significantly improve the overall quality of regulatory analysis.