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781.
W. C. Benton 《决策科学》2013,44(6):1139-1153
Each year U.S. News and World Report evaluates more than 5,000 U.S. hospitals, of which approximately 3% are considered the best hospitals in America, and hospital profitability has emerged as a business objective for these hospitals. This study investigates the profitability performance of the best (highest quality) hospitals in the United States. A 9‐year longitudinal investigation of profitability for the best hospitals in the United States is conducted. The results offer evidence that the primary drivers of hospital profitability are the case mix index and daily bed capacity. In terms of hospital profitability, there appears to be a tradeoff between these two factors. Finally, caution must be used when ranking U.S. News and World Report Honor Roll hospitals, in terms of profitability and performance.  相似文献   
782.
Slack can act as a double‐edged sword. While it can buffer against environmental threats to help ensure business continuity, slack can also be costly and reduce profitability. In this study we focus on operational slack, the form related to the firm's production processes. We investigate the role of operational slack on firm survival during its venture stage when its survival is significantly challenged by environmental threats. Specifically, we explore how change in three types of environmental uncertainty, namely dynamism, complexity, and lack of munificence, affect the relationship between operational slack and venture survival. Results suggest that with an increase in environmental uncertainty, operational slack lowers the likelihood of venture failure.  相似文献   
783.
While firm internationalization processes have been understood as being dynamic, the dimension of speed has rarely been the main focus of research efforts, which, until a decade ago, focused principally on explaining sequences of entry modes and choices of markets. The emergence of the study of international entrepreneurship has enhanced the role of speed, although this has usually been measured in terms of the time lag between a firm's foundation and its initial international action, with little attempt at defining and explaining the speed of the process once it is under way. This study reviews the concept of speed from an internationalization perspective, describes the multidimensional nature of the concept and sets out the different aspects that link timescales with the types of changes – continuous and discontinuous – that take place during internationalizing processes. The paper concludes with a research agenda as a guide for future work on considering the role of speed in the internationalization process.  相似文献   
784.
The economically optimal sample size in a food safety test balances the marginal costs and marginal benefits of increasing the sample size. We provide a method for selecting the sample size when testing beef trim for Escherichia coli O157:H7 that equates the averted costs of recalls and health damages from contaminated meats sold to consumers with the increased costs of testing while allowing for uncertainty about the underlying prevalence rates of contamination. Using simulations, we show that, in most cases, the optimal sample size is larger than the current sample size of 60 and, in some cases, it exceeds 120. Moreover, lots with a lower prevalence rate have a higher expected damage because contamination is more difficult to detect. Our simulations indicate that these lots have a higher optimal sampling rate.  相似文献   
785.
Quantitative microbiological risk assessment was used to quantify the risk associated with the exposure to Legionella pneumophila in a whirlpool. Conceptually, air bubbles ascend to the surface, intercepting Legionella from the traversed water. At the surface the bubble bursts into dominantly noninhalable jet drops and inhalable film drops. Assuming that film drops carry half of the intercepted Legionella, a total of four (95% interval: 1–9) and 4.5×104 (4.4×104 – 4.7×104) cfu/min were estimated to be aerosolized for concentrations of 1 and 1,000 legionellas per liter, respectively. Using a dose‐response model for guinea pigs to represent humans, infection risks for active whirlpool use with 100 cfu/L water for 15 minutes were 0.29 (~0.11–0.48) for susceptible males and 0.22 (~0.06–0.42) for susceptible females. A L. pneumophila concentration of ≥1,000 cfu/L water was estimated to nearly always cause an infection (mean: 0.95; 95% interval: 0.9–~1). Estimated infection risks were time‐dependent, ranging from 0.02 (0–0.11) for 1‐minute exposures to 0.93 (0.86–0.97) for 2‐hour exposures when the L. pneumophila concentration was 100 cfu/L water. Pool water in Dutch bathing establishments should contain <100 cfu Legionella/L water. This study suggests that stricter provisions might be required to assure adequate public health protection.  相似文献   
786.
Research on dynamic capabilities emphasizes the importance and role of organizational routines in explaining interfirm differences in performance. While performance differences are well documented, few empirical analyses explore the processes inside organizations that lead to dynamic capabilities or attempt to define and measure their performance effects. This paper examines one type of dynamic capability – the development and introduction of new process technologies in semiconductor manufacturing. This dynamic capability is an important source of competitiveness in the semiconductor industry, given the short product lifecycles, rapid price declines, and rapid technological advances that define the industry. Because much of the knowledge that underpins semiconductor manufacturing is idiosyncratic, firm-level R&D organization and information technology practices that facilitate problem solving and learning-based improvement provide important and enduring advantages. We derive models of the rate of improvement in manufacturing yield (i.e. the quality of production) and cycle time (i.e. the speed of production) following the development and introduction of new process technologies in manufacturing facilities, and test the empirical specifications of these models. The ways in which semiconductor manufacturers accumulate experience and articulate and codify knowledge within the manufacturing environment build new process development and introduction dynamic capabilities that improve performance.  相似文献   
787.
Due to growing work-family demands, supervisors need to effectively exhibit family supportive supervisor behaviors (FSSB). Drawing on social support theory and using data from two samples of lower wage workers, the authors develop and validate a measure of FSSB, defined as behaviors exhibited by supervisors that are supportive of families. FSSB is conceptualized as a multidimensional superordinate construct with four subordinate dimensions: emotional support, instrumental support, role modeling behaviors, and creative work-family management. Results from multilevel confirmatory factor analyses and multilevel regression analyses provide evidence of construct, criterion-related, and incremental validity. The authors found FSSB to be significantly related to work-family conflict, work-family positive spillover, job satisfaction, and turnover intentions over and above measures of general supervisor support.  相似文献   
788.
Let G be a graph and be the complement of G. The complementary prism of G is the graph formed from the disjoint union of G and by adding the edges of a perfect matching between the corresponding vertices of G and . For example, if G is a 5-cycle, then is the Petersen graph. In this paper we consider domination and total domination numbers of complementary prisms. For any graph G, and , where γ(G) and γ t (G) denote the domination and total domination numbers of G, respectively. Among other results, we characterize the graphs G attaining these lower bounds. Research supported in part by the South African National Research Foundation and the University of KwaZulu-Natal.  相似文献   
789.
We apply charismatic leadership theory to the historic 2008 United States presidential election, in hopes of inspiring dialogue around how leadership theory can inform the critical process of evaluating and electing public leaders. While numerous leadership theories are relevant to understanding the 2008 election, charismatic leadership theory highlights aspects of the leader, followers, and the unfolding economic crisis that are particularly relevant in helping us to understand how a relatively inexperienced political outsider ascended to the US Presidency. Given the potential perils and challenges newly elected President Barack Obama faces in the months and years ahead, we also suggest four core strategies rooted in charismatic leadership theory that may help him capitalize on his early charismatic appeal, as well as avoid the pitfalls of charisma that have plagued some of his predecessors.  相似文献   
790.
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