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981.
By reengineering their department's core processes, materiel managers can expand their role in the health care setting while realizing significant cost savings. Using a team model, Inova Health System materiel management staff integrated their processes for vendor selection, purchasing, inventory reduction, and utilization across three hospitals and ancillary services. An integrated approach at all levels of the organization gained buy-in from administrators and staff systemwide.  相似文献   
982.
This paper tests the effect on stock value of an expected change in future trading costs. The capitalized value of a reduction in trading costs is hypothesized to increase the stock value, a trading cost effect. Improved liquidity reduces trading costs. Inclusion as an S&P 500 Index replacement stock is an event hypothesized to increase liquidity. We use 114 observations between January 1, 1983 and October 12, 1989 of stocks added to the Index as replacements for stocks removed. The abnormal return of each stock is regressed against the ratio of the bidask spread to the price of the stock, the change in trading volume of the stock, and the open interest in the Index futures contracts at the close of the month prior to the replacement announcement. We find that the positive abnormal returns for replacement stocks are related to increased daily trading volume after inclusion in the Index. Further, the trading cost effect is proportional to percentage bid-ask spreads prior to inclusion. The trading cost effect increases as trading in derivatives of the Index increases. The volume and stock price changes after replacement are not transitory, indicating an improvement in liquidity. Three alternate hypotheses suggested in prior research to explain the abnormal returns for replacement stocks are tested. Testing each of the three models previously considered: price pressure, inelastic demand curves, and information, we find that none can be accepted with statistical confidence. The abnormal returns of Index replacement stocks are consistent with rational pricing of an anticipated reduction in future transaction costs. This anticipated reduction is capitalized in the value of the stock at the time of the replacement announcement. These results are consistent with a trading cost effect.  相似文献   
983.
This paper explores the relationship between organizational context and the interpretation of strategic issues by examining the hypothesis that CEOs' interpretations of foreign investment in the USA are influenced by the organizational context in which they are embedded. Three aspects of organizational context - the global business experience of the firm; the firm's level of organizational inertia (as represented by firm age and size); and the resources available for responding - are examined as predictors of CEOs' perceptions of foreign investment as a threat or an opportunity. Analysis of data from 320 organizations, controlled by industry, shows that global business experience, firm size, and perceived capability are significant predictors of the perception of threat and opportunity. the discussion addresses the implications of these findings for future research on issue interpretation and organizational context.  相似文献   
984.
Environmental issues are restructuring markets and redirecting capital flows throughout the world. An outline is provided of concerns facing the development of an environmentally responsible or ‘environmental finance’ perspective. It reviews the major ways in which organizations are responding to environmental threats and opportunities in the three major branches of finance — corporate finance, investments and financial institutions — highlighting in particular novel programs and initiatives. In the past, financial concerns have exacerbated the degradation of the natural environment; in the future, they probably hold the key to their preservation.  相似文献   
985.
An effective emergency medical service (EMS) response to emergency medical calls during extreme weather events is a critical public service. Nearly all models for allocating EMS resources focus on normal operating conditions. However, public health risks become even more critical during extreme weather events, and hence, EMS systems must consider additional needs that arise during weather events to effectively respond to and treat patients. This paper seeks to characterize how the volume and nature of EMS calls are affected during extreme weather events with a particular focus on emergency preparedness. In contrast to other studies on disaster relief, where the focus is on delivery of temporary commodities, we focus on the delivery of routine emergency services during blizzards and hurricane evacuations. The dependence of emergency service quality on weather conditions is explored through a case study using real-world data from Hanover County, Virginia. The results suggest that whether it is snowing is significant in nearly all of the regression models. Variables associated with increased highway congestion, which become important during hurricane evacuations, are positively correlated with an increased call volume and the likelihood of high-risk calls. The analysis can aid public safety leaders in preparing for extreme weather events.  相似文献   
986.
This paper describes and develops a model for calculating location-based strategic values of foreclosed properties considered for acquisition and redevelopment by community development corporations (CDCs). A property’s strategic value refers to its proximity to site-specific neighborhood amenities and disamenities (e.g. schools, public transit, distressed properties), given the relative importance of that proximity to CDC organizational and community objectives. We operationalize the concept of strategic value, and apply this concept to a salient public sector decision problem. Using data and value assessments from a CDC engaged in foreclosed housing redevelopment, we compute measures of strategic value for a set of acquisition candidates. We show that strategic values can differ in systematic ways depending on the types of amenities and disamenities identified as relevant for CDC acquisition decisions, the relative importance assigned to those amenities and disamenities, and the utility maximization objectives of the CDC. We conclude by proposing a multi-criteria decision model for foreclosed housing acquisition and redevelopment which incorporates a theory of residential housing impacts for which strategic value measures are a special case.  相似文献   
987.
In this study, three different estimators for estimating the proportion of a sensitive attribute in survey sampling are compared at equal protection of the respondents. The three estimators considered are due to Odumade and Singh (2009, Comm. Statist. Theory Methods) , Singh and Sedory (2011, Sociological Methods and Research) and a new estimator obtained by minimizing a chi‐squared distance. A SAS Macro is developed to compare these three estimators using a simulation study at equal protection of the respondents. A set of data from a real face‐to‐face interview was collected using two decks of cards and has been analyzed. The results are discussed.  相似文献   
988.
The allocation problem for multivariate stratified random sampling as a problem of stochastic matrix integer mathematical programming is considered, minimizing the estimated covariance matrix of estimated means subject to fixed cost or fixed total sample size. With these aims the asymptotic normality of sample covariance matrices for each strata is established. Some alternative approaches are suggested for its solution. An example is solved by applying the proposed techniques.  相似文献   
989.
990.
Les enquêtes à mode de collecte mixte, dans lesquelles le choix du mode de réponse est laissé aux personnes interrogées, sont de plus en plus répandues. Cette possibilité du choix du mode de réponse peut induire une confusion entre deux sortes d'effets : les effets de sélection et les effets de mesure. L'estimation séparée de ces deux effets est impossible à partir des seules données d'une enquête à mode de collecte mixte. Dans cet article, nous montrons comment la même estimation devient possible à partir d'une comparaison entre les résultats d'une enquête à mode de collecte mixte et ceux d'un enquête à mode de collecte unique basées sur le même questionnaire. La méthode que nous proposons permet d'estimer l'effet du mode de réponse sur la moyenne et la variance d'une variable de réponse continue. Elle est illustrée par l'estimation des effets du mode de réponse sur six questions relatives aux opinions vis‐à‐vis des enquêtes.  相似文献   
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