The robust economic statistical design of the Hotelling's T2 chart

ABSTRACT

Economic statistical designs aim at minimizing the cost of process monitoring when a specific scenario or a set of estimated process and cost parameters is given. But, in practice the process may be affected by more than one scenario which may lead to severe cost penalties if the wrong design is used. Here, we investigate the robust economic statistical design (RESD) of the T² chart in an attempt to reduce these cost penalties when there are multiple scenarios. Our method is to employ the genetic algorithm (GA) optimization method to minimize the total expected monitoring cost across all distinct scenarios. We illustrate the effectiveness of the method using two numerical examples. Simulation studies indicate that robust economic statistical designs should be encouraged in practice.     

Equality of Opportunity versus Equality of Opportunity Sets

We characterize two different approaches to the idea of equality of opportunity. Roemer’s social ordering is motivated by a concern to compensate for the effects of certain (non-responsibility) factors on outcomes. Van de gaer’s social ordering is concerned with the equalization of the opportunity sets to which people have access. We show how different invariance axioms open the possibility to go beyond the simple additive specification implied by both rules. This offers scope for a broader interpretation of responsibility-sensitive egalitarianism.     

Social aspects of economic readjustment in Hungary: A consideration of the role of social-economic indicators

Social Accounting Matrices have been used as a means of analysing national economic structure but it is argued in this paper that their usefulness could be enhanced if they were designed to include compatible sets of socio-economic indicators which might reflect physical stocks and flows rather than strictly monetary flows. This paper considers ways in which this might be accomplished, giving particular consideration to optional approaches based on economic, social and quality of life indicators. Three approaches to providing supplementary information to the conventional Social Accounting Matrix model are considered. These include the incorporation of indicators of characteristics of households, the disaggregation of data to a geographical base and use of indicators of social attitudes and expectations. Although work continues on the first two of these suggestions, certain results concerning the third are presented. A consideration is given to the use of available secondary data to meet the needs identified. It is shown, however, that such information fails to meet the objectives of the study for various reasons. It is concluded that the necessary data can only be collected by surveys. Preliminary results of a survey carried out in Hungary beginning in May 1991 by Gallup/Hungary are presented. This information reflects attitudes of the population toward changes which are taking place and would seem to provide a means of estimating perceptions of changes in expected quality of life that result from the current efforts toward economic readjustment in Hungary.     

Value of Information in Closed Loop Supply Chains

We explore the value of information (VOI) in the context of a firm that faces uncertainty with respect to demand, product return, and product recovery (yield). The operational decision of interest in matching supply with demand is the quantity of new product to order. Our objective is to evaluate the VOI from reducing one or more types of uncertainties, where value is measured by the reduction in total expected holding and shortage costs. We start with a single period model with normally distributed demands and returns, and restrict the analysis to the value of full information (VOFI) on one or more types of uncertainty. We develop estimators that are predictive of the value and sensitivity of (combinations of) different information types. We find that there is no dominance in value amongst the different types of information, and that there is an additional pay‐off from investing in more than one type. We then extend our analysis to the multi‐period case, where returns in a period are correlated with demands in the previous period, and study the value of partial information (VOPI) as well as full information. We demonstrate that our results from the single period model (adapted for VOPI) carry‐over exactly. Furthermore, a comparison with uniformly distributed demand and return show that these results are robust with respect to distributional assumptions.     

Temporary Migration Overseas and Household Labor Supply: Evidence from Urban Philippines

The impact of international migration on the labor supply of workers' nonmigrant relatives has not been well documented in the literature. Using household survey data representing mostly overseas contract workers, i.e., temporary migrants, this paper shows that labor supplies of migrants and their nonmigrant relatives are inseparable. Migrants reduce the labor supply of nonmigrant relatives, which translates into lower earnings from local labor markets. Households substitute income for more leisure – a significant and previously little recognized benefit of emigration for Philippine households. This benefit varies by gender of nonmigrants and is generally higher for men.     

Swastika,pink triangle and yellow star—the destruction of sexology and the persecution of homosexuals in Nazi Germany

Much early sexological research, indeed the very concept of sexology, was the work of German Jews. Hitler's rise to power first curtailed, then prevented, and finally destroyed all German sex research and a flourishing sex reform movement. Once the scientific and scholarly study of sex had come to an end, the sexual ideology‐of Nazism, which was antisemitic, antifeminist, and homophobic, could easily be put into practice. The official persecution of German homosexuals between 1933 and 1945 is discussed as a typical policy of a régime which rejected the rational and critical approach to sexual questions.