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21.
Acquisitive growth strategies continue to be popular, in spite of increasing evidence that they often do not enhance the financial performance of acquiring firms and may adversely affect innovation. However, some acquisitions are associated with both increases in financial performance and a strengthened commitment to R&D while others experience decreases in both. Multiple theories have been offered to explain acquisitions and their outcomes, but few have received strong empirical support. This paper describes a multiple rater, multiple-case study of acquisitions that had highly favourable outcomes and others that experienced highly unfavourable outcomes. All twelve of the high performing acquisitions studied were found to exhibit the dual characteristics of friendliness during acquisition negotiations and resource complementarities between the two firms. Additionally, debt played an important role in the success (low to moderate debt) or lack of success (high or extraordinary debt) in 21 of the 24 acquisitions studied. Inadequate target evaluation was a factor in 11 of the 12 acquisitions with low performance. Importantly, the results of both sets of acquisitions suggested that a configuration of attributes affected post-acquisition performance. Other findings both supported and contradicted commonly held beliefs about acquisitions, as well as highlighted variables not typically associated with acquisition strategies. The study provides directions for future theory development and empirical research on acquisitions.  相似文献   
22.
We analyse theoretical properties of the slice sampler. We find that the algorithm has extremely robust geometric ergodicity properties. For the case of just one auxiliary variable, we demonstrate that the algorithm is stochastically monotone, and we deduce analytic bounds on the total variation distance from stationarity of the method by using Foster–Lyapunov drift condition methodology.  相似文献   
23.
Leaders form different quality leader–member exchange (LMX) relationships with their subordinates. This variable treatment termed LMX differentiation can have negative effects on individuals' behavior and attitudes. In this study, we examined the cross-level main effect of justice climate on task performance and the moderating role of justice climate on the relationship between LMX differentiation and task performance. We tested these two hypotheses using a field study of 90 subordinates nested under 27 supervisors. Procedural justice climate, not distributive justice climate, was found to positively influence subordinate task performance. Further, distributive justice climate, not procedural justice climate, was found to moderate the LMX differentiation–task performance relationship; such that the relationship was positive when distributive justice climate was high and negative when distributive justice climate was low. Findings and future directions are discussed.  相似文献   
24.
The benchmark dose (BMD) approach has gained acceptance as a valuable risk assessment tool, but risk assessors still face significant challenges associated with selecting an appropriate BMD/BMDL estimate from the results of a set of acceptable dose‐response models. Current approaches do not explicitly address model uncertainty, and there is an existing need to more fully inform health risk assessors in this regard. In this study, a Bayesian model averaging (BMA) BMD estimation method taking model uncertainty into account is proposed as an alternative to current BMD estimation approaches for continuous data. Using the “hybrid” method proposed by Crump, two strategies of BMA, including both “maximum likelihood estimation based” and “Markov Chain Monte Carlo based” methods, are first applied as a demonstration to calculate model averaged BMD estimates from real continuous dose‐response data. The outcomes from the example data sets examined suggest that the BMA BMD estimates have higher reliability than the estimates from the individual models with highest posterior weight in terms of higher BMDL and smaller 90th percentile intervals. In addition, a simulation study is performed to evaluate the accuracy of the BMA BMD estimator. The results from the simulation study recommend that the BMA BMD estimates have smaller bias than the BMDs selected using other criteria. To further validate the BMA method, some technical issues, including the selection of models and the use of bootstrap methods for BMDL derivation, need further investigation over a more extensive, representative set of dose‐response data.  相似文献   
25.
In the United States and around the rest of the world, there is a renewed focus on ensuring that schools are providing students with the skills necessary to compete in the global economy. High-quality summer learning programs are an ideal vehicle to help students gain content knowledge and develop innovative skills: they provide time for individual exploration and hands-on, experiential opportunities that can instill a lifelong love of learning that carries into the classroom and the workforce.  相似文献   
26.
Van Hook J  Zhang W  Bean FD  Passel JS 《Demography》2006,43(2):361-382
The utility of postcensal population estimates depends on the adequate measurement of four major components of demographic change: fertility, mortality, immigration, and emigration. Of the four components, emigration, especially of the foreign-born, has proved the most difficult to gauge. Without "direct" methods (i.e., methods identifying who emigrates and when), demographers have relied on indirect approaches, such as residual methods. Residual estimates, however are sensitive to inaccuracies in their constituent parts and are particularly ill-suited for measuring the emigration of recent arrivals. Here we introduce a new method for estimating foreign-born emigration that takes advantage of the sample design of the Current Population Survey (CPS): repeated interviews of persons in the same housing units over a period of 16 months. Individuals appearing in a first March Supplement to the CPS but not the next include those who died in the intervening year, those who moved within the country, and those who emigrated. We use statistical methods to estimate the proportion of emigrants among those not present in the follow-up interview. Our method produces emigration estimates that are comparable to those from residual methods in the case of longer-term residents (immigrants who arrived more than 10 years ago), but yields higher--and what appear to be more accurate--estimates for recent arrivals. Although somewhat constrained by sample size, we also generate estimates by age, sex, region of birth, and duration of residence in the United States.  相似文献   
27.
The present study examined the career advancement prospects of MIS and non-MIS employees, as well as the relationships of career advancement prospects with job performance evaluations, job satisfaction, career satisfaction, and organizational commitment for MIS and non-MIS professionals and managers. Participants included 134 MIS professionals and managers and 397 non-MIS professionals and managers of a large communications company. The results provided no evidence that MIS employees experience more restricted career advancement prospects than non-MIS employees. In addition, job performance evaluations generally had positive effects on career advancement prospects; career advancement prospects had a number of positive effects on job satisfaction, career satisfaction, and organizational commitment; and job satisfaction and career satisfaction had positive effects on organizational commitment. These findings are related to prior research, suggestions for future research are offered, and implications for the management of MIS employees are identified.  相似文献   
28.
The importance of sensitivity analysis information in linear programming has been stressed in the management science literature for some time. Indeed, Gal [3] has devoted an entire text to just this issue. Linear programs with common inputs (cost coefficients or right-hand-side values) present a problem in that classical sensitivity analysis does not allow for the simultaneous changes required to determine the sensitivity of these models to common inputs. We first survey the approaches previously developed for simultaneous-change sensitivity analysis and cast them in the framework of the special common input case. These general techniques are compared to a simple aggregate variable technique that has not received attention in the literature.  相似文献   
29.
30.
We use a regression discontinuity design to study how academic probation affects outcomes and course‐taking behaviors at a large public university in the United States. Consistent with past work, students placed on probation improve their grade point average (GPA) in the subsequent semester. We document that part of this GPA improvement is attributable to strategic course‐taking, and there is significant heterogeneity in these behaviors across race. Non‐minority students placed on probation attempt fewer credits, easier courses, and are more likely to withdraw from courses in the following term. In contrast, underrepresented minorities exhibit few of these behaviors, consistent with past work that suggests black and Hispanic students are less likely to possess helpful institutional knowledge and use available support systems such as academic counseling. (JEL I20, I23)  相似文献   
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