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We focus on the fertility of Swedish men and women who lived in a consensual or marital union in the 1970s and 1980s, and where at least one of the partners had children before they entered that union. Couples without any children before the current union were included for contrast. We find clear evidence that couples wanted a shared biological child, essentially regardless of how many children (if any) they had before their current union. The shared child seems to have served to demonstrate commitment to the union, as did its conversion into a formal marriage. We have not found much support for the hypothesis that our respondents sought to enter parenthood to attain adult status. A second birth might have been valued because it provided a sibling for the first child -- a half-sibling acting as a substitute for a full sibling -- but our evidence for such eåects is contradictory. Our analysis makes it very clear that parity progression depends on whose parity we consider. 相似文献
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This paper develops multivariate models to describe homogamy or, more generally, marriage preferences, for corresponding characteristics of brides and grooms. The purpose of these models is to obtain interpretable measures of the degree of homogamy (or marriage preference) on one dimension and to adjust these measures for homogamy on other dimensions. The models are applied to a sample of marriages in Montevideo, Uruguay, with pairs of corresponding variables for the brides and grooms. The analysis estimates the unadjusted and adjusted levels of homogamy on previous marital status, age, education, religion, and location. Homogamy on location, or propinquity, is the single most important variable. Previous marital status and age describe the readiness or eligibility to marry and are associated in their effect on homogamy. Education and religion describe vertical and horizontal differentiation of marriage partners, respectively. The multivariate analysis verifies that these dimensions are largely independent of each other. 相似文献
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In this paper we review the literature on appointment policies, specifically in terms of the objective function commonly used and the assumptions made about the behavior of demand. First, we provide an economic framework to analyze the problem. Based on this framework we make a critical analysis of the objective functions used in the literature. We also question the validity of the assumption made throughout the literature that demand is exogenous and independent of customers' waiting times. We conclude that the objective functions used in the literature are appropriate only in the case of a central planner facing a demand that is unresponsive to waiting time. For other scenarios, such as a private server facing a demand that does react to waiting time, these objective functions are only shortcuts for the real objective functions that must be used. A more general model is then proposed that fits these scenarios well. Finally, we determine the impact of using the literature's objective functions on optimal appointment policies. 相似文献
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FELIPE CARO RODRIGO ANDALAFT XIMENA SILVA ANDRES WEINTRAUB PEDRO SAPUNAR MANUEL CABELLO 《Production and Operations Management》2003,12(3):290-306
An important issue being discussed for Chilean pine plantation policies is the application of environmental protection measures when managing its timber areas. Typical measures, already in place in more developed countries, include imposing riparian strips and protecting fragile soils from the use of heavy machinery. While environmental protection measures have been considered vital for decades, so far there has been almost no attempt to quantify both the benefits and costs of these measures. This paper attempts to measure the costs associated with the main measures which can help both the forestry firms and the government evaluate the cost impact of the new environmental protection regulations being studied. The analysis for different environmental scenarios is carried out by modifying a mixed integer LP, currently used for tactical planning by one forestry firm. 相似文献
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