Computing the Distributions of Economic Models via Simulation

We study a Monte Carlo algorithm for computing marginal and stationary densities of stochastic models with the Markov property, establishing global asymptotic normality and O_P(n^–1/2) convergence. Asymptotic normality is used to derive error bounds in terms of the distribution of the norm deviation.     

Credit at the Corner Store: An Analysis of Resource Exchange among Detroit‐Area Urban Poor

This ethnographic study examines how and why Detroit‐area credit‐constrained members of the urban poor relied on owners/employees of corner convenience stores, known as “party stores,” for accessing short‐term, interest‐free informal credit services. Findings indicate that informal credit at party stores functioned as a low‐ or no‐cost alternative to formal credit and high‐cost fringe banking services such as payday loans, both of which were inaccessible and/or cost prohibitive for informants. These data contribute empirically to a growing body of research on “credit invisibility” by exploring these populations' use of informal credit mechanisms. Findings also make a theoretical contribution by highlighting the importance of resource exchange networks through which members of the urban poor build strong yet disposable social ties in order to respond to economic shocks, combat food insufficiency, and survive economic destitution.     

The Big Tent for Statistics: Mentoring Required

Research supports the positive impact of mentoring on both job and career satisfaction. Recognizing this, the American Statistical Association (ASA) has started a new mission-centered focus on mentoring. This article describes the development and implementation of meeting-based mentoring programs at four ASA conferences in 2014 and 2015. We present results of the feedback evaluations from program participants and use them to motivate recommendations for creating and running conference mentoring programs and overcoming common challenges. These recommendations are applicable to creating and running conference mentoring programs in any field. We conclude with a discussion of the opportunities for the ASA to augment its mentoring programs in support of the professional development of its members.     

关于少数民族概念的几个问题－－少数民族权利理论问题研究

“少数民族”一词是一个被广泛使用的概念。“少数民族”概念在各个国家和地区各有不同的界定,每一个国家根据其自身所要调整的民族关系,来定义其特定的少数民族概念,并进而保障少数民族权利。在中国,少数民族概念已经深入人心,这是民族概念在当代中国社会和中国宪法体系中所具有的独特意义和价值。     

Toward a Radical Model of Social Work in Rural Communities

“Rural” areas as distinct from “urban” continue to be defined by greater personal interactions and less emphasis on formal systems of support. This reality rests in contradiction to the overwhelming majority of social work scholarship and theory development which takes place in an urban context. As such the present-day act of being a “social worker” in a rural community can, in many ways, feel like a bad fit, back-applying the model of an urban generalist into an environment whose organic community ties the social work model itself was originally designed to substitute for. In recognition of this, it is necessary to develop a “combined” model of practice for social work with rural communities and peoples. The fundamental distinction to be made is that rural social work, in its most radical form, is less concerned with adapting persons to the Gesellschaft than it is with strengthening the capacity of the Gemeinschaft to provide the kind of support capacity it historically has, taking into account changes and challenges resulting from factors such as globalization, urban sprawl, and cultural change.     

The Frustrating Effects of Just Missing the Jackpot: Slot Machine Near-Misses Trigger Large Skin Conductance Responses, But No Post-reinforcement Pauses

Near-misses in slot machines resemble jackpot wins but fall just short. Previous research has demonstrated that near-misses are behaviorally reinforcing despite the absence of monetary reward. We assessed the hedonic properties of near-misses by measuring the time between outcome delivery and the initiation of the next spin—the post-reinforcement pause (PRP) and skin conductance responses (SCRs) for losses, near-misses, and a range of wins (5, 15, 25, 50 or 250 credits) while participants (N = 122) played a slot machine simulator. PRPs and SCRs were compared for 40 low frequency and 22 high frequency slots players who were non-problem gamblers, 37 at risk players, and 23 problem gamblers. For winning outcomes, PRPs and SCRs tracked monotonically with win size such that progressively larger wins were associated with progressively larger PRPs and SCRs. Near-misses with jackpot symbols landing on the first two reels had significantly larger SCRs than regular losses, and other types of near misses. Crucially, PRPs for this kind of near-miss were significantly smaller than all wins, and when non-parametric statistics were used, significantly smaller than regular losses. This pattern of large SCRs and small PRPs suggest that these are highly frustrating outcomes that stimulate appetitive components of the reward system to promote continued gambling.     

Application of TOC/OPT rules in a medium sized shop

Abstract

Abstract. Theory of constraints (TOC) and optimized production technology (OPT) are frequently presented as the better options for production control systems. Despite this enthusiasm, there is very little literature on how these principles can be implemented in practice without having to resort to the expensive proprietary software. In this paper we present a case study in which the OPT/TOC ideas were implemented without using the software. Management's major concern was reduction of work in process and increased delivery performance. It was decided to test whether the ideas of OPT/TOC were applicable in this environment and more importantly to which extent these two performance measures could be improved. The paper reports on the methodology used to test the OPT/TOC ideas in this shop and presents some early results of improvement, as well as some new problems which arose due to the new approach.     

Why Care about Scientific Controversies?

Since Kuhn claimed that scientific controversies are not always settled by means of rational evaluations of the intrinsic merits of competing theories, the view that the history of science should be recounted by examining the background of scientific controversies and how these controversies came to be settled has become a real heuristic maxim for the historian of science. We take issue with this view by arguing that controversies are not relevant by themselves but only insofar as one can make something out of them. Two important questions then arise: what did one come to learn from a given controversy and what came out of this apprenticeships. We compare Pauline Mazumdar's and Alfred Tauber's approaches to the history of immunology and argue that only the latter addressed these questions. In so doing, he was able to show the extension in which modern immunology is an outcome of Metchnikoff's success in correcting Haeckel's “fundamental biogenetic law”.     

Estimation for High‐Dimensional Linear Mixed‐Effects Models Using ℓ1‐Penalization

Abstract. We propose an ?₁‐penalized estimation procedure for high‐dimensional linear mixed‐effects models. The models are useful whenever there is a grouping structure among high‐dimensional observations, that is, for clustered data. We prove a consistency and an oracle optimality result and we develop an algorithm with provable numerical convergence. Furthermore, we demonstrate the performance of the method on simulated and a real high‐dimensional data set.