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111.
In this paper, we demonstrate how public opinion surveys can be designed to collect information pertinent to computational behavior modeling, and we present the results of a public opinion and behavior survey conducted during the 2009–2010 H1N1 influenza pandemic. The results are used to parameterize the Health Belief Model of individual health‐protective decision making. Survey subjects were asked questions about their perceptions of the then‐circulating influenza and attitudes towards two personal protective behaviors: vaccination and avoidance of crowds. We empirically address two important issues in applying the Health Belief Model of behavior to computational infectious disease simulation: (1) the factors dynamically influencing the states of the Health Belief Model variables and (2) the appropriateness of the Health Belief Model in describing self‐protective behavior in the context of pandemic influenza. 相似文献
112.
This paper concerns the forecasting of seasonal intraday time series that exhibit repeating intraweek and intraday cycles. A recently proposed exponential smoothing method involves smoothing a different intraday cycle for each distinct type of day of the week. Similar days are allocated identical intraday cycles. A limitation is that the method allows only whole days to be treated as identical. We introduce a new exponential smoothing formulation that allows parts of different days of the week to be treated as identical. The result is a method that involves the smoothing and initialisation of fewer terms. We evaluate forecasting up to a day ahead using two empirical studies. For electricity load data, the new method compares well with a range of alternatives. The second study involves a series of arrivals at a call centre that is open for a shorter duration at the weekends than on weekdays. Among the variety of methods considered, the new method is the only one that can model in a satisfactory way in this situation, where the number of periods on each day of the week is not the same. 相似文献
113.
This paper proposes new models for locating emergency medical services (EMS) by incorporating survival functions for capturing multiple-classes of heterogeneous patients. The Maximal Expected Survival Location Model for Heterogeneous Patients (MESLMHP) aims to maximize the overall expected survival probability of multiple-classes of patients, whereby different classes could be defined according to agreed patient categories based on response time targets, or by capturing differing medical conditions each with a corresponding survival function. Furthermore, we propose and demonstrate an approximation approach to solving the extended stochastic version of MESLMHP, which utilizes queuing theory to permit the modeling of congestion and utilization at each ambulance station, and does not require assumptions to be made on the utilization of ambulances. Both models are demonstrated using data from the ambulance service in Wales. We show that our multiple outcome measures and survival-maximizing approach, rather than one based on average response time targets alone or a single patient class provides more effective EMS ambulance allocations. 相似文献
114.
Sankalp Chaturvedi Michael J. Zyphur Richard D. Arvey Bruce J. Avolio Gerry Larsson 《The Leadership Quarterly》2012,23(2):219-232
In this study, we examined the moderating influences of gender and age with respect to testing the heritability of leadership emergence. A large data base of 12,112 twins from Sweden was used in the current study to decompose the variance of emergent leadership into an unobservable genetic component and environmental components that are either common or unshared among twin pairs. Consistent with prior leadership research on genetics, we found that a genetic factor is able to explain a significant proportion of the variation across individuals in predicting how twins perceive their emergent leadership behavior (about 44% for women and 37% for men). Furthermore, we also found that the magnitude of genetic influence on emergent leadership varied with age, but only for women with the heritability estimate being highest for the mid-age women versus lowest for the older women. Implications for advancing research on the genetic and environmental influences on leadership emergence are discussed. 相似文献
115.
Using data collected from 107 pairs of identical and 89 pairs of fraternal female twins, this study examined the genetic and environmental associations between transformational leadership and leadership role occupancy. Results show that 78% of the covariance between the two leadership variables was attributable to overlapping genetic factors, while 22% of the covariance to overlapping environmental factors. In particular, 13% (2%) of the variance in leadership role occupancy was accounted for by the same genetic (environmental) factors related to transformational leadership. Unique sets of genetic and environmental variables, which are not associated with transformational leadership, explained 16% and 69% of the variance in leadership role occupancy, respectively. The results suggest that multiple manifestations of leadership (i.e., transformational leadership and leadership role occupancy) are differentially heritable. Although the association between these two variables is largely due to overlapping genetic rather than environmental factors, unique (i.e., non-overlapping) genetic and environmental influences still play an important role in impacting these leadership variables. 相似文献
116.
We examined the validity of three leadership approaches in an organization in India. We used a multi-theory and multi-method design to competitively test transformational leadership theory, the nurturant–task leadership model, and a local organization-specific leadership model. Transformation leadership theory is one of the most widely studied and accepted theories in Western countries and is viewed as a universalistic leadership approach. The nurturant–task leadership model was developed in India and viewed as a culture-specific leadership approach. We also developed a local leadership model, called RDO, a pseudonym for the organization, and viewed it as an organization-specific leadership approach, using a qualitative analysis of interview data. The overall results of our qualitative–quantitative work provide strong support for the RDO leadership model, some support for a nurturant–task leadership model, and minimal support for transformational leadership theory. These results suggest that research designs that include a multi-theory, multi-methods approach in a single culture have the potential to increase our understanding of leadership processes. 相似文献
117.
Gianmarco I. P. Ottaviano Giovanni Peri 《Journal of the European Economic Association》2012,10(1):152-197
This paper calculates the effects of immigration on the wages of native US workers of various skill levels in two steps. In the first step we use labor demand functions to estimate the elasticity of substitution across different groups of workers. Second, we use the underlying production structure and the estimated elasticities to calculate the total wage effects of immigration in the long run. We emphasize that a production function framework is needed to combine own‐group effects with cross‐group effects in order to obtain the total wage effects for each native group. In order to obtain a parsimonious representation of elasticities that can be estimated with available data, we adopt alternative nested‐CES models and let the data select the preferred specification. New to this paper is the estimate of the substitutability between natives and immigrants of similar education and experience levels. In the data‐preferred model, there is a small but significant degree of imperfect substitutability between natives and immigrants which, when combined with the other estimated elasticities, implies that in the period from 1990 to 2006 immigration had a small effect on the wages of native workers with no high school degree (between 0.6% and +1.7%). It also had a small positive effect on average native wages (+0.6%) and a substantial negative effect (−6.7%) on wages of previous immigrants in the long run. 相似文献
118.
Sascha Kraus J. P. Coen Rigtering Mathew Hughes Vincent Hosman 《Review of Managerial Science》2012,6(2):161-182
Entrepreneurial Orientation (EO) is often mentioned as an antecedent of growth, competitive advantage and superior performance,
and prior empirical research has often shown a positive relationship between EO and performance appears to exist. However,
an important question that remains unanswered is what effect EO might have on firm performance during periods of economic
crisis, and the severe environmental turbulence that accompany such crises. This research is a first investigation towards
the effects of EO on the performance of small and medium sized firms during the current global economic crisis. In this study
we use the multidimensional model of EO and test a series of hypotheses pertaining to its performance effects using survey
data gathered from 164 Dutch SMEs. The present research shows that proactive firm behavior positively contributes to SME performance
during the economic crisis. We further show that innovative SMEs do perform better in turbulent environments, but those innovative
SMEs should minimize the level of risk and should take action to avoid projects that are too risky. 相似文献
119.
This article examines the existing contractual arrangements and industry standards in private equity. It shows that investors
are, in principle, capable of structuring their particular investments according to their own preferences, there are a range
of governance problems and risks that could be potentially hazardous for some classes of investors. We examine the circumstances
where existing industry codes and legal tools can be used to address the problems that arise in relation to private equity
and buyout activity. 相似文献
120.
Carlos A. Bana e Costa Mónica D. Oliveira 《Omega》2012,40(4):424-436
In the context of increasing demands for social and financial accountability of universities, the required implementation of transparent faculty evaluation systems constitutes a challenge and an opportunity for universities strategically aligning the activity of academic staff with the university goals. However, despite growing interest in the performance appraisal of faculty, only a few reported studies propose models that cover the full range of academic activities and the models in use are typically based on ad hoc scoring systems that lack theoretical soundness. This article approaches faculty evaluation from an innovative comprehensive perspective. Based on the concepts and methods of multiple criteria value measurement, it proposes a new faculty evaluation model that addresses the whole range of academic activities and can be applied within and across distinct scientific areas, while respecting their specificities. Constructed through a socio-technical process, the model was designed for and adopted by the Instituto Superior Técnico, the engineering school of the Technical University of Lisbon. The model has a two-level hierarchical additive structure, with top-level evaluation areas specified by second-level evaluation criteria. A bottom non-additive third level accounts for the quantitative and qualitative dimensions of academic activity related to each evaluation criterion. The model allows (a) the comparison of the performance of academic staff with performance targets reflecting the strategic policy concerns of university management; (b) the definition of the multicriteria value profile of each faculty member at the top level of the evaluation areas; (c) the computation of an overall value score for each faculty member, through an optimisation procedure that makes use of a flexible system of weights and (d) the assignment of faculty members to rating categories. 相似文献