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941.
We develop, in this article, a sales model for movie and game products at Blockbuster. The model assumes that there are three sales components: the first is from consumers who have already committed to purchasing (or renting) a product (e.g., based on promotion of, or exposure to, the product prior to its launch); the second comes from consumers who are potential buyers of the product; and the third comes from either a networking effect on closely tied (as in a social group) potential buyers from previous buyers (in the case of movie rental and all retail products) or re‐rents (in the case of game rental). In addition, we explicitly formulate into our model dynamic interactions between these sales components, both within and across sales periods. This important feature is motivated by realism, and it significantly contributes to the accuracy of our model. The model is thoroughly tested against sales data for rental and retail products from Blockbuster. Our empirical results show that the model offers excellent fit to actual sales activity. We also demonstrate that the model is capable of delivering reasonable sales forecasts based solely on environmental data (e.g., theatrical sales, studio, genre, MPAA ratings, etc.) and actual first‐period sales. Accurate sales forecasts can lead to significant cost savings. In particular, it can improve the retail operations at Blockbuster by determining appropriate order quantities of products, which is critical in effective inventory management (i.e., it can reduce the extent of over‐stocking and under‐stocking). While our model is developed specifically for product sales at Blockbuster, we believe that with context‐dependent modifications, our modeling approach could also provide a reasonable basis for the study of sales for other short‐Life‐Cycle products.  相似文献   
942.
We propose a theory of task trade between countries that have similar relative factor endowments and technological capabilities, but may differ in size. Firms produce differentiated goods by performing a continuum of tasks, each of which generates local spillovers. Tasks can be performed at home or abroad, but offshoring entails costs that vary by task. In equilibrium, the tasks with the highest offshoring costs may not be traded. Among the remainder, those with the relatively higher offshoring costs are performed in the country that has the higher wage and the higher aggregate output. We discuss the relationship between equilibrium wages, equilibrium outputs, and relative country size.  相似文献   
943.
We investigate the welfare properties of the one‐sector neoclassical growth model with uninsurable idiosyncratic shocks. We focus on the notion of constrained efficiency used in the general equilibrium literature. Our characterization of constrained efficiency uses the first‐order condition of a constrained planner's problem. This condition highlights the margins of relevance for whether capital is too high or too low: the factor composition of income of the (consumption‐)poor. Using three calibrations commonly considered in the literature, we illustrate that there can be either over‐ or underaccumulation of capital in steady state and that the constrained optimum may or may not be consistent with a nondegenerate long‐run distribution of wealth. For the calibration that roughly matches the income and wealth distribution, the constrained inefficiency of the market outcome is rather striking: it has much too low a steady‐state capital stock.  相似文献   
944.

Background

Pregnancy after infertility is a challenging experience. The first-trimester screening test may add stress. Partner support reduces psychological distress in pregnant women after spontaneous conception. No data are available for women who conceive via assisted reproductive technology.

Aim

To assess whether there was a difference between couples who underwent assisted reproductive technology and couples who conceived spontaneously in the support they felt they provided to their partner and whether their perception of support received from their partner reduced their distress.

Methods

This longitudinal prospective study included 52 women (spontaneous conception) and 53 women (assisted reproductive technology), as well as their partners. Participants completed the state scale of the State-Trait Anxiety Inventory, the Edinburgh Depression Scale, and two partner-support subscales of the Dyadic Coping Inventory: before prenatal testing (gestational age 12 weeks), immediately after receiving the results (gestational age of approximately 14 weeks), and once all the prenatal screenings had been completed (gestational age 22 weeks).

Findings

Women who underwent assisted reproductive technology felt less able to help their partner cope with stress and felt their partner was less able to help them cope with stress than women with spontaneous pregnancy. This difference was not observed in men. Higher perceived partner support lowered the anxiety and depression of couples who conceived spontaneously, but did not benefit couples who followed fertility treatment.

Conclusion

These results add to our knowledge of the emotional state of women and their partners during pregnancy after infertility. This knowledge may allow prenatal care providers to offer specialized counselling to women and their partners in the transition from infertility to parenthood.  相似文献   
945.
Economic and rational‐choice theories suggest that individuals form unions or have children because these decisions increase their subjective well‐being or “happiness.” We investigate this relation using within‐MZ (identical) twin pair estimates to control for unobserved factors, such as optimistic preferences, that may simultaneously affect happiness, partnerships, and fertility. Our findings, based on Danish twins aged 25–45 and 50–70 years old, include the following. (1) Currently being in a partnership has large positive effects on happiness. (2) A first child substantially increases well‐being, in analyses without controls for partnerships, and males enjoy an almost 75 percent larger happiness gain from a first‐born son than from a first‐born daughter; however, only females enjoy a happiness gain from the first‐born child with controls for partnerships. (3) Additional children beyond the first child have a negative effect on subjective well‐being for females, while there is no effect for males. (4) Ever having had children does not significantly affect the subjective well‐being of males or females aged 50–70 years.  相似文献   
946.
947.
A representative sample of undergraduate and postgraduate international students at a large Australian university (n = 979, 64% females) completed a mail-back survey examining their perceptions of social connectedness. Four aspects of social connectedness were investigated: (1) connectedness in Melbourne, (2) social mixing and interaction with co-culturals and Australians, (3) involvement in organisations, associations and groups, and (4) connections to home and family. The majority of students report being well-connected to others in Melbourne, although some desire increased personal support from people who know and care about them. Connectedness in Melbourne is related to students’ cultural background and communication skills in the new culture and their evaluation of their perceived academic progress. Students from Asian countries reveal different patterns to other students, especially in the relationships between connectedness and interactions with co-culturals. Awareness of these and other differences among international students from varying cultural backgrounds can help target assistance in achieving a sense of well-being.  相似文献   
948.
The analytic models used by family demographers would be strengthened by the concept of social capital, placed in the context of social exchange theory. Using that concept to designate resources that emerge from social ties, the authors advance five propositions: 1) social capital is a multidimensional attribute of an individual; 2) the dimensions of social capital are the number of relationships a person has, their quality (strength), and the resources available through those relationships; 3) group membership and interaction facilitate the development of social capital; 4) the structural properties of groups influence the development of social capital; and 5) the acquisition and maintenance of social capital is a major motivator of human behavior. The formation of sexual partnerships, the birth and rearing of children, and both intragenerational and intergenerational transfers constitute major forms of investment in social capital in virtually all societies.  相似文献   
949.
Very frequent family interaction, daily or more often, significantly lowered the morale scores in a sample of retired men and women who were highly satisfied with their family life, even after controlling for health, income and other measures of satisfaction. In contrast to other research which has shown that it is the quality not the quantity which affects morale, these findings suggested that both quantity and quality of family interaction were important to morale. An explanation from the social exchange perspective indicates that there is an optimal level of family interaction beyond which the costs outweight the benefits.  相似文献   
950.
In what percentage of married couples do wives outearn their husbands, and, moreover, how persistent are these patterns? This study systematically examined variation in point-in-time estimates across alternative measures of earnings, definitions of types of couples, and data sources and gauged the persistence of these patterns for a period of three calendar years using data from the 2000 Current Population Survey and the 1996–2000 Survey of Income and Program Participation. Among the findings are that in 19% to 30% of all married couples, wives have higher earnings than their husbands. In 60% of such couples, this arrangement persists over the three-year period; for the rest, this arrangement is transitory.  相似文献   
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