Three-level main-effects designs exploiting prior information about model uncertainty

To explore the projection efficiency of a design, Tsai, et al [2000. Projective three-level main effects designs robust to model uncertainty. Biometrika 87, 467–475] introduced the Q criterion to compare three-level main-effects designs for quantitative factors that allow the consideration of interactions in addition to main effects. In this paper, we extend their method and focus on the case in which experimenters have some prior knowledge, in advance of running the experiment, about the probabilities of effects being non-negligible. A criterion which incorporates experimenters’ prior beliefs about the importance of each effect is introduced to compare orthogonal, or nearly orthogonal, main effects designs with robustness to interactions as a secondary consideration. We show that this criterion, exploiting prior information about model uncertainty, can lead to more appropriate designs reflecting experimenters’ prior beliefs.     

Asthma Patients' Activities and Air Pollution: A Semiparametric Censored Regression Analysis

Asthma patients' health status may be especially sensitive to some types of air pollution, but the evidence on this is mixed. We explore the effects of ground-level ozone on asthma patient's activities, breaking apart the usual aggregated category of leisure into indoor and outdoor activities, and differentiating those by whether the activities were active or inactive. Applying the semiparametric censored estimation method we demonstrate that even though the period over which activities were observed was relatively low in ozone levels, there is a significant impact of ozone on a few activities. The (non-ozone) economic and demographic variables in the model play significant roles in explaining the allocation of time among seven activities, suggesting the suitability of the approach for other household decision-making contexts.     

Beyond recruitment: Predictors of differential participation in a national antihunger organization

Surprisingly little research has sought to explain differential participation after recruitment into social movement organizations (SMOs). This study examines the influence of several sets of predictors on participation by members of a national organization in the antihunger movement. The findings highlight the importance of incentive, ideological, and microstructural factors for differential participation and suggest that favorable perceptions of SMOs also promote participation. Final remarks address the implications of the findings for the social movement and voluntary organization literatures.     

Circuit optimization via sequential computer experiments: design of an output buffer

In electrical engineering, circuit designs are now often optimized via circuit simulation computer models. Typically, many response variables characterize the circuit's performance. Each response is a function of many input variables, including factors that can be set in the engineering design and noise factors representing manufacturing conditions. We describe a modelling approach which is appropriate for the simulator's deterministic input–output relationships. Non-linearities and interactions are identified without explicit assumptions about the functional form. These models lead to predictors to guide the reduction of the ranges of the designable factors in a sequence of experiments. Ultimately, the predictors are used to optimize the engineering design. We also show how a visualization of the fitted relationships facilitates an understanding of the engineering trade-offs between responses. The example used to demonstrate these methods, the design of a buffer circuit, has multiple targets for the responses, representing different trade-offs between the key performance measures.     

Poland's crisis and East European socialism

Conclusion We began this article by asking whether the Polish crisis is a socialist or a Polish disease. By citing the structural factors, we brought out the common difficulties affecting all East European societies in their political and economic development. These difficulties arose out of the transition from extensive to intensive economic growth and the consequent need to replace political mobilization of the population with their political integration. The structural contradictions occurred together with conjunctural developments in the world economy, the collapse of detente, the post-war demographic explosion, and natural calamities. Poland was least able to cope with these structural and conjunctural dynamics. The result was a society united on a national basis in its conflicts with the Party State apparatus. This conflict was never resolved by Solidarity nor by the subsequent military coup.While Poland and Romania had quite similar structural and conjunctural dynamics, it was only in Poland that the constellation of nation-specific factors yielded a societal reaction of system-threatening character. Looking at the rest of Eastern Europe, we do not see a similar constellation of factors. Rather, the combination of structural, conjunctural, and specific conditions has prevented the deeper contradictions from evolving into Solidarity-type mass movements of the Polish variety. Thus, we believe that the Polish developments will not be replicated in any of the other East European countries in the foreseeable future.Does this mean that the Polish experience is so unique that it is without relevance for the other East European states? On the contrary, the recognition of common structural problems points to fundamental conflicts in all the countries of actually existing socialism. The essence of these conflicts may be the same. It is the ability to identify and deal with them that distinguishes one East European regime from another. This ability varies with the specific and conjunctural factors as applied to each country. While there is little likelihood that the Polish disease will spread, this is partly because the other East European states are beginning to take preventive measures. In other words, they are learning from the Polish experience.There are several indicators that these regimes have learned from the Polish crisis. We can summarize them in the following predictions:First, we believe that state power and the repressive apparatus of the various East European countries will be reinforced and made more effective. This applies not so much to overt shows of force but to more sophisticated methods of social control and repression: e.g., limiting information channels, dispersing dissident groups, giving in to workers protests before they spread, taking practical measures to prevent consumer shortages from getting out of hand, and the like.Second, we can expect that oppositional forces, especially intellectuals, will be increasingly restricted in their ability to formulate and articulate system-threatening demands. The East European states will take any measures - jail, slander, internal deportation, cooptation, forced emigration - to make sure that intellectuals' contact with workers is weakened or at least strictly supervised.Third, we can expect the Eastern European states to take further measures to integrate potential system-threatening movements into the official system. We will see further attempts to improve the access possibilities for those social interests that have up to now been neglected, e.g. in physical and social infrastructures, neglected regions. Moreover, there will be renewed efforts to make the system of political socialization (education, propaganda, culture) more effective. Finally, we can expect anti-corruption campaigns within the State, Party, and industrial bureaucracies as the elites attempt to make these organs more legitimate in the eyes of the population.In recent months there seems to be considerable evidence that the East European regimes have taken all these measures. There have been attempts to re-invigorate the official trade unions. Yuri Andropov's succession was marked by a highly publicized anti-corruption campaign designed to win favor among rank-and-file workers. In Romania there have been exhortations towards more self-sufficiency and self-management, so that individual producers will be less dependent on State retail outlets, and the country less dependent on costly foreign imports. The reduction in East-West trade and decline of detente have also given more leeway for the East European repressive apparatus to crack down on dissidents and oppositional movements.With reduced trade, the economic benefits of detente no longer exist as a restraining factor on the authorities. The West now has reduced influence on domestic politics in East Europe. The combination of integration and repressive measures has so far prevented the structural contradictions from growing into true political crises of the Polish variety. Eastern Europe (and Poland) is remarkably quiet.With the broad enthusiasm fostered in the West by the rise of Solidarity, it is understandable that its brutal demise had generated parallel feelings of disillusionment. It would be erroneous to consider the Polish events as an archetype for Eastern Europe. The problems of East European regimes reflect a general system crisis (economic and political), each country's response depends on specific local conditions and fortuitous conjunctures. If the Polish events are to be understood, they must be explained as a variant in a larger East European context.Having concentrated on the crisis aspects in Poland and Romania should not blind us from the fact that these systems have an amazing ability to reproduce themselves - to muddle through. Actually existing socialism is more than simply brute force. Each of the East European societies exhibits a complex dialectic between the forces of functional stability and the forces of immanent contradictions. As such, in addition to their structural aspects, we must analyze each of these societies in their differing vulnerability to conjunctural events and in their specific political, social, and cultural characters.For those who seek to replace actually existing socialism with a more emancipatory socialism, the Polish crisis constitutes a key point of departure. It should be discussed both in terms of what it means for Poland, and for Eastern Europe. The Polish events provide further evidence that the tasks of social theory reside as much in explaining why societies muddle through as why they fall apart.     

RESIDENTIAL MORTGAGE RISK CHARACTERISTICS*

This paper applies discriminant analysis to a relatively large sample of residential mortgages-some of which have defaulted or have been foreclosed and others of which have remained untroubled at least until the date of the last observation-in an attempt to derive a function which would allow mortgage lenders to increase their accuracy of predicting mortgage difficulty. From the data available for testing, no improvement in predictability is obtained, because it is thought that the data may already have been badly biased by the screening process of the loan officers which had already taken place and by the post-loan origination nature of the important variables in mortgage difficulty. The latter is confirmed by discriminant models of post-origination variables which are successful. It is concluded that changes in home value, changes in mortgagor income, mortgage assumption, and regional economic considerations are the major explanations of mortgage difficulty.     

Unmet Need for Family Planning in Developing Countries and Implications for Population Policy

Unmet need for family planning has been a core concept in international population discourse for several decades. This article reviews the history of unmet need and the development of increasingly refined methods of its empirical measurement and delineates the main questions that have been raised about unmet need during the past decade, some of which concern the validity of the concept and others its role in policy debates. The discussion draws heavily on empirical research conducted during the 1990s, much of it localized, in‐depth studies combining quantitative and qualitative methodologies. Of the causes of unmet need other than those related to access to services, three emerge as especially salient: lack of necessary knowledge about contraceptive methods, social opposition to their use, and health concerns about possible side effects. The article argues that the concept of unmet need for family planning, by joining together contraceptive behavior and fertility preferences, encourages an integration of family planning programs and broader development approaches to population policy. By focusing on the fulfillment of individual aspirations, unmet need remains a defensible rationale for the formulation of population policy and a sensible guide to the design of family planning programs.     

Examining cross-state variation in the increase in father-only families

Each state has the power to establish its own policy and laws relating to child custody determination. The number of single-parent families with children that are headed by fathers has been growing in the United States. This paper explores the extent of cross-state variation in the prevalence in father-only families in 1990, and the extent to which there was cross-state variation in the increase in father-only families in the 1980s. The 1980 and 1990 Public Use Microdata Samples (PUMS) drawn from the US decennial censuses are used. Decomposition analyses of growth indicate that increases in the number of father-only families occurred across all states during this period, but at varying rates. The primary reason for the increase in most states is an increase in the proportion of ever-married single-parent families that are headed by a father. It is for these families that are headed by divorced or separated parents that state policy relating to child custody determination is most relevant.