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991.
The manufacturing complexity of many high‐tech products results in a substantial variation in the quality of the units produced. After manufacturing, the units are classified into vertically differentiated products. These products are typically obtained in uncontrollable fractions, leading to mismatches between their demand and supply. We focus on product stockouts due to the supply–demand mismatches. Existing literature suggests that when faced with product stockouts, firms should satisfy all unmet demand of a low‐end product by downgrading excess units of a high‐end product (downward substitution). However, this policy may be suboptimal if it is likely that low‐end customers will substitute with a higher quality product and pay the higher price (upward substitution). In this study, we investigate whether and how much downward substitution firms should perform. We also investigate whether and how much low‐end inventory firms should withhold to strategically divert some low‐end demand to the high‐end product. We first establish the existence of regions of co‐production technology and willingness of customers to substitute upward where firms adopt different substitution/withholding strategies. Then, we develop a managerial framework to determine the optimal selling strategy during the life cycle of technology products as profit margins shrink, manufacturing technology improves, and more capacity becomes available. Consistent trends exist for exogenous and endogenous prices.  相似文献   
992.
Swartwood RM  Veach PM  Kuhne J  Lee HK  Ji K 《Omega》2011,63(2):161-181
Online grief communities represent relatively new forms of peer support. However, the degree to which they are helpful for individual grieving processes is unknown. To date, no research has evaluated the type or quality of support exchanged in online grief communities. To begin to address these questions, this study analyzed 564 messages from internet grief websites to: (1) classify the type of helping skills used, and (2) extract themes contained in the content of the messages. Messages selected for analysis were the first response to an original post, assuming they would be the first effort to provide support to a grieving individual. Results revealed a majority of responses contained self-disclosure. Themes in the messages suggested provision of more than "one-way" support; messages themes also included exchanging hope for the future by sharing one's own story, validating the grief experience, providing resources, and exchanging psychosocial support. Clinical implications and research recommendations are discussed.  相似文献   
993.
A股市场上大股东减持的时机选择和市场反应研究   总被引:1,自引:0,他引:1       下载免费PDF全文
利用公开披露的减持公告数据,从短时间窗口考察大股东减持的时机选择能力以及减持披露后的市场反应机制的研究结果显示,减持公告前后累计超额收益(CAR)呈先升后降的倒V形,CAR[-20,-1]和CAR[0,20]分别高达4.12%和-2.61%,大股东在减持中表现出精准的时机选择能力,并获利丰厚,而市场认为减持传达了估值偏高或前景不佳的新信息,对此作出了显著的负面反应。在公告当日,市场对绩差公司、民营控股公司的大股东减持以及大额的减持作出更大的负面反应;在公告后的较长时间内,绩差公司、控股股东的减持负面影响更持久。可见,精准的时机选择能力反映出大股东在交易中的确利用了重要的私有信息,减持前高达4.12%的超额收益为强化监管提供了有力的经验支持。  相似文献   
994.
The professional literature has not adequately addressed the behavioral and social factors that contribute to different coping outcomes for African American elder caregivers as compared to non African Americans. Awareness and understanding of these unique experiences would better prepare professionals to work with such clients. This study examines the predictors of emotional distress among 46 African American women who provide care to dependent elderly parents. Multivariate statistical analyses show that elder caregivers' rating of quality of life, their years of caregiving, as well are their poor heath constitute significant predictors of risk for depression. The results of the study provide support for the inclusion of more culturally appropriate measures of caregiver distress, and provide insights to inform social work practice, policy and research concerning African American female elder caregivers in the 21st century.  相似文献   
995.
Objectives. We describe the geography, population composition, and housing stock of extremely affluent neighborhoods and evaluate the extent to which conclusions about these neighborhoods differ across definitions of affluence. Methods. Using Census 2000 data on tracts in the 100 largest U.S. metropolitan areas, we compare neighborhoods at the very top of the income distribution (highest 2 percent) to their counterparts in lower‐income categories. The distributions for median household income, median family income, per‐capita income, and the household income ratio allow us to define affluence in alternative ways. Results. Contrary to past findings, rich neighborhoods are no longer concentrated in the Northeast, and they exhibit substantial proportions of foreign‐born and Asian residents and average labor force participation rates. Other of their characteristics (e.g., educational level, professional‐managerial employment, housing size and value) seem more predictable. Although certain results vary depending on how affluence is defined, the majority do not. Conclusion. Our analysis lays an empirical foundation for future work on affluent neighborhoods, which have received scant research attention. It also makes a conceptual contribution, demonstrating that such neighborhoods stand out irrespective of the definitional approach taken.  相似文献   
996.
This paper seeks to discover whether the known inaccuracy of informant recall about their communication behavior can be accounted for by experimentally varying the time period over which recall takes place. The experiment took advantage of a new communications medium (computer conferencing) which enabled us to monitor automatically all the interactions involving a subset of the computer network. The experiment itself was administered entirely by the computer, which interviewed informants and recorded their responses. Variations in time period failed to account for much of the inaccuracy, which continues, as in previous experiments at an unacceptably high level. One positive finding did emerge: although the informants did not know with whom they communicated, the informants en masse seemed to know certain broad facts about the communication pattern. All other findings were negative. For example, it is impossible to predict the people an informant claimed to communicate with but did not; and it is impossible to predict who the five people are that an informant forgot to mention that she or he had communication with. Thus, despite their presumed good intentions, our findings here confirm what we have learned from six previous experiments: What people say about their communications bears no resemblance to their behavior. This suggests that other forms of data gathering, based on questions which require that informants recall their behavior, may well be suspect.  相似文献   
997.

When heterogeneous players make strategic investment decisions in multi-stage contests, they might conserve resources in a current contest to spend more in a subsequent contest, if the degree of heterogeneity in the current (subsequent) contest is sufficiently large (small). We confirm these predictions using data from German professional soccer, in which players are subject to a one-match ban if they accumulate five yellow cards. Players with four yellow cards facing the risk of being suspended for the next match are (i) less likely to be fielded when the heterogeneity in the current match increases and (ii) more likely to receive a fifth yellow card in the current match when heterogeneity in the next match increases or heterogeneity in the next match but one (when they return from their ban) decreases.

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This article investigates the interaction between oligopoly power, labor unionization, and worker wages. Using data from the Panel Study of Income Dynamics for workers in manufacturing industries little evidence is found that workers are exploited by oligopolistic employers, but rather wages for production workers increase with both unionization and employer's market power. There is evidence, however, that unionization reduces variation in wages due to increased oligopoly power.  相似文献   
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