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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   
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ABSTRACT

The one-sample Wilcoxon signed rank test was originally designed to test for a specified median, under the assumption that the distribution is symmetric, but it can also serve as a test for symmetry if the median is known. In this article we derive the Wilcoxon statistic as the first component of Pearson's X 2 statistic for independence in a particularly constructed contingency table. The second and third components are new test statistics for symmetry. In the second part of the article, the Wilcoxon test is extended so that symmetry around the median and symmetry in the tails can be examined seperately. A trimming proportion is used to split the observations in the tails from those around the median. We further extend the method so that no arbitrary choice for the trimming proportion has to be made. Finally, the new tests are compared to other tests for symmetry in a simulation study. It is concluded that our tests often have substantially greater powers than most other tests.  相似文献   
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We consider likelihood ratio, score and Wald tests for a three-way random effects ANOVA model. Competitor tests are compared using criteria such as small sample power, asymptotic relative efficiency, and convenient null distribution. The final choice is between a new test and two tests long used in practice.  相似文献   
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Goodness of fit for thei ordered categories discrete uniform distribution can be carried out using Pearson's X2 pstatistic and its components. Applications of this technique are considered and comparisons made with recently suggested empirical uniform distribution  相似文献   
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Summary.  Data in the social, behavioural and health sciences frequently come from observational studies instead of controlled experiments. In addition to random errors, observational data typically contain additional sources of uncertainty such as missing values, unmeasured confounders and selection biases. Also, the research question is often different from that which a particular source of data was designed to answer, and so not all relevant variables are measured. As a result, multiple sources of data are often necessary to identify the biases and to inform about different aspects of the research question. Bayesian graphical models provide a coherent way to connect a series of local submodels, based on different data sets, into a global unified analysis. We present a unified modelling framework that will account for multiple biases simultaneously and give more accurate parameter estimates than standard approaches. We illustrate our approach by analysing data from a study of water disinfection by-products and adverse birth outcomes in the UK.  相似文献   
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This study addresses three questions about the population of children and families served in the highest level of care in the child welfare system in New York State residential treatment centers (RTCs): (1) How prevalent are emotional and behavioral problems in the youth entering RTCs? (2) Has the proportion of youth with such problems increased compared to 10 years ago? (3) Are there identifiable subgroups of youth entering RTCs? One-fourth of RTC admissions in fiscal year 2001 were randomly selected from a representative sample of 16 RTCs. The study completed a standardized data collection instrument based on a review of agency records, and included information that was known at the time each child was admitted. The results show significant increases compared to t10 years earlier in the proportion of youth with mental health problems and juvenile justice backgrounds. The findings suggest that youth who traditionally have been served by other systems of care are now being served in the child welfare system. The increased treatment needs of these youth and the heterogeneity of the RTC population have important implications for policies, programs, and practice.  相似文献   
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Despite evidence that individuals with schizophrenia spectrum disorders experience significant and persistent symptoms of anxiety, there are few reports of the use of empirically supported treatments for anxiety in this population. This article describes how we have tried to adapt mindfulness interventions to help individuals with schizophrenia who experience significant anxiety symptoms. Although mindfulness has been widely used to help individuals without psychosis, to our knowledge, this is the first study adapting it to help those with schizophrenia manage worry and stress. We provide an overview of the intervention and use an individual example to describe how our treatment development group responded. We also explore directions for future research of mindfulness interventions for schizophrenia.  相似文献   
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