The Social Participation of Blacks: A Proposed Synthesis of Two Competing Theories

Discrepant findings have typified the research concerning the social participation of blacks in America. The bulk of the findings would seem to posit three competing theories, one emphasizing low participation levels on the part of blacks, and the later two emphasizing high levels of social participation. These theories are examined and a synthesis of the "isolation" and "compensation" models is proposed. By examining both formal and informal types of social participation on the part of blacks, it is argued that both theories are viable toward explaining variation within black participation levels in particular and toward mediating the discrepant findings as they have been previously offered in general. Some support is found for such a proposed synthesis.     

The immigrant experience: Houstonians’ family attitudes and behaviors

ABSTRACT

Although there is extensive scholarship that examines differences in family behaviors and attitudes between whites and blacks, there are very few studies that examine these differences across whites, blacks, Latinos, and Asians in the United States. In the current study, we do so by examining data from the 2011 Houston Area Survey. We explore Houstonians’ likelihood of engaging in interracial relationships, attitudes toward working mothers, and attitudes toward same-sex marriage. Houston was selected as the target of the study given its rise as the most racially and ethnically diverse metropolitan area in the nation. Non-white Houstonians are more likely to date members of other racial/ethnic groups. With regard to attitudes toward working mothers, only Latino and Asian immigrants hold less accepting views than whites. Finally, the results with regard to same-sex marriage equality suggest that increased migration and diversity within Houston could hasten social change and acceptance.     

Considerations on the ‘Replication Problem’ in Sociology

We re-examine the so-called “replication problem” in sociology—a scarcity of published studies dedicated to reproducing findings from prior research. We do this in part by considering the larger epistemological traditions of the natural sciences and humanities. We make three primary arguments: that (1) replication studies are more prevalent than is commonly perceived, (2) calls for and discussions of replication do not attend enough to issues of theory, and (3) we should reconsider as a discipline how we evaluate replications. In developing this third argument, we draw on the concept of episteme, discussing two epistemes that concurrently exist in sociology: the scientific project and the aesthetic object. The former overlaps with approaches to knowledge growth in the natural sciences, the latter with the humanities. We propose that sociology is situated between these extremes, presenting unique challenges for replication research. In particular, nuanced considerations of replications in sociology foreclose any simplistic accounts of a replication problem in the discipline.     

Testing Set-Point Theory in a Swiss National Sample: Reaction and Adaptation to Major Life Events

Set-point theory posits that individuals react to the experience of major life events, but quickly adapt back to pre-event baseline levels of subjective well-being in the years following the event. A large, nationally representative panel study of Swiss households was used to examine set-point theory by investigating the extent of adaptation following the experience of marriage, childbirth, widowhood, unemployment, and disability. Our results demonstrate that major life events are associated with marked changes in life satisfaction and, for some events (e.g., marriage, disability), these changes are relatively long lasting even when accounting for normative, age related changes.     

Online control by attributes in the presence of classification errors with variable inspection interval

ABSTRACT

The procedure for online control by attribute consists of inspecting a single item at every m items produced (m ≥ 2). On each inspection, it is determined whether the fraction of the produced conforming items decreased. If the inspected item is classified as non conforming, the productive process is adjusted so that the conforming fraction returns to its original status. A generalization observed in the literature is to consider inspection errors and vary the inspection interval. This study presents an extension of this model by considering that the inspected item can be rated independently r (r ≥ 1) times. The process is adjusted every time the number of conforming classifications is less than a, 1 ≤ a ≤ r. This method uses the properties of an ergodic Markov chain to obtain the expression for the average cost of this control system. The genetic algorithm methodology is used to search for the optimal parameters that minimize the expected cost. The procedure is illustrated by a numerical example.     

Robustness of the student t based M-estimator

This paper considers the maximum likelihood type (M) estimator based on Student's t distribution for the location/scale model. The Student t M-estimator is generally thought to be robust to outliers. This paper shows that this is only true if the degrees of freedom parameter is kept fixed. By contrast, if the degrees of freedom parameter is also estimated from the data, the influence functions for the scale and degrees of freedom parameter become unbounded. Moreover, the influence function of the location parameter remains bounded, but its change-of-variance function is unboi~nded. The intuitioil behind these results is explained in the paper. The rates at which both the influence functions and the change-of-variance function diverge to infinity, are very slow. Tliis implies that outliers have to be extremely large in order to become detrimental to the performance of the Student t based M-estimator with estimated degrees of freedom. The theoretical results are illustrated in a a simulation experiment using several related competing estimators and several distributions for the error process.     

On the Internal Structure of Cities

We prove the existence of a symmetric equilibrium in a circular city in which businesses and housing can both be located anywhere in the city. In this equilibrium, firms balance the external benefits from locating near other producers against the costs of longer commutes for workers. An equilibrium city need not take the form of a central business district surrounded by a residential area. We propose a general algorithm for constructing equilibria, and use it to study the way land use is affected by changes in the model's underlying parameters.     

Strengthening a linear reformulation of the 0-1 cubic knapsack problem via variable reordering

The 0-1 cubic knapsack problem (CKP), a generalization of the classical 0-1 quadratic knapsack problem, is an extremely challenging NP-hard combinatorial optimization problem. An effective exact solution strategy for the CKP is to reformulate the nonlinear problem into an equivalent linear form that can then be solved using a standard mixed-integer programming solver. We consider a classical linearization method and propose a variant of a more recent technique for linearizing 0-1 cubic programs applied to the CKP. Using a variable reordering strategy, we show how to improve the strength of the linear programming relaxation of our proposed reformulation, which ultimately leads to reduced overall solution times. In addition, we develop a simple heuristic method for obtaining good-quality CKP solutions that can be used to provide a warm start to the solver. Computational tests demonstrate the effectiveness of both our variable reordering strategy and heuristic method.