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1.
Marc Frenette 《LABOUR》2004,18(2):207-232
It is well known that the earnings of recent cohorts of immigrant men have fallen further behind native‐born men. Using several years of Canadian Census data, this study finds that immigrants have turned to self‐employment at a much faster rate than the native born. In addition, the earnings gap between self‐employed immigrant and native‐born men has not grown with successive cohorts, but rather has followed a cyclical movement: narrowing at the peak, and widening in times of weaker economic activity. However, immigrants choosing self‐employment still face challenges, as their earnings are far below native‐born earnings, and convergence is a lengthy process.  相似文献   

2.
《Risk analysis》2018,38(7):1444-1454
The performance of fire protection measures plays a key role in the prevention and mitigation of fire escalation (fire domino effect) in process plants. In addition to passive and active safety measures, the intervention of firefighting teams can have a great impact on fire propagation. In the present study, we have demonstrated an application of dynamic Bayesian network to modeling and safety assessment of fire domino effect in oil terminals while considering the effect of safety measures in place. The results of the developed dynamic Bayesian network—prior and posterior probabilities—have been combined with information theory, in the form of mutual information, to identify optimal firefighting strategies, especially when the number of fire trucks is not sufficient to handle all the vessels in danger.  相似文献   

3.
We study buyer‐determined procurement auctions where both price and non‐price characteristics of bidders matter for being awarded a contract. Although, in scoring auctions bidders perfectly know how price and non‐price attributes determine the awarding of the contract, this remains uncertain in buyer‐determined auctions where the buyer is free to choose once all bids have been submitted. We analyze the impact of information bidders have with respect to the buyer's awarding decision. As we show theoretically whether it is in the buyer's interest to conceal the impact of non‐price characteristics depends on how important the quality aspects of the procured good are to the buyer: The more important quality aspects are, the more interesting concealment becomes. In a counterfactual analysis using data from a large European procurement platform, we analyze the reduction of non‐price information available to the bidders. Confirming our hypothesis, for auction categories where bidders’ non‐price characteristics strongly influence buyers’ decisions concealment of non‐price information leads to an increase in buyers’ surplus of up to 15% due to higher competitive pressure and lower bids. Conversely, for categories where bidders’ non‐price characteristics are of little importance concealment of non‐price information leads to a decrease in buyers’ surplus of up to 6%.  相似文献   

4.
Determining the most effective public warnings to issue during a hazardous environmental event is a complex problem. Three primary questions need to be answered: Who should take protective action? What is the best action? and When should this action be initiated? Warning triggers provide a proactive means for emergency managers to simultaneously answer these questions by recommending that a target group take a specified protective action if a preset environmental trigger condition occurs (e.g., warn a community to evacuate if a wildfire crosses a proximal ridgeline). Triggers are used to warn the public across a wide variety of environmental hazards, and an improved understanding of their nature and role promises to: (1) advance protective action theory by unifying the natural, built, and social themes in hazards research into one framework, (2) reveal important information about emergency managers’ risk perception, situational awareness, and threat assessment regarding threat behavior and public response, and (3) advance spatiotemporal models for representing the geography and timing of disaster warning and response (i.e., a coupled natural‐built‐social system). We provide an overview and research agenda designed to advance our understanding and modeling of warning triggers.  相似文献   

5.
L Kopylev  J Fox 《Risk analysis》2009,29(1):18-25
It is well known that, under appropriate regularity conditions, the asymptotic distribution for the likelihood ratio statistic is χ2. This result is used in EPA's benchmark dose software to obtain a lower confidence bound (BMDL) for the benchmark dose (BMD) by the profile likelihood method. Recently, based on work by Self and Liang, it has been demonstrated that the asymptotic distribution of the likelihood ratio remains the same if some of the regularity conditions are violated, that is, when true values of some nuisance parameters are on the boundary. That is often the situation for BMD analysis of cancer bioassay data. In this article, we study by simulation the coverage of one- and two-sided confidence intervals for BMD when some of the model parameters have true values on the boundary of a parameter space. Fortunately, because two-sided confidence intervals (size 1–2α) have coverage close to the nominal level when there are 50 animals in each group, the coverage of nominal 1−α one-sided intervals is bounded between roughly 1–2α and 1. In many of the simulation scenarios with a nominal one-sided confidence level of 95%, that is, α= 0.05, coverage of the BMDL was close to 1, but for some scenarios coverage was close to 90%, both for a group size of 50 animals and asymptotically (group size 100,000). Another important observation is that when the true parameter is below the boundary, as with the shape parameter of a log-logistic model, the coverage of BMDL in a constrained model (a case of model misspecification not uncommon in BMDS analyses) may be very small and even approach 0 asymptotically. We also discuss that whenever profile likelihood is used for one-sided tests, the Self and Liang methodology is needed to derive the correct asymptotic distribution.  相似文献   

6.
Much attention has been paid to lengthy wait times in emergency departments (EDs) and much research has sought to improve ED performance. However, ED congestion is often caused by the inability to move patients into the wards while the wards in turn are often congested primarily due to patients waiting for a bed in a long‐term care (LTC) facility. The scheduling of clients to LTC is a complex problem that is compounded by the variety of LTC beds (different facilities and room accommodations), the presence of client choice and the competing demands of the hospital and community populations. We present a Markov decision process (MDP) model that determines the required access in order for the census of patients waiting for LTC in the hospitals to remain below a given threshold. We further present a simulation model that incorporates both hospital and community demand for LTC in order to predict the impact of implementing the policy derived from the MDP on the community client wait times and to aid in capacity planning for the future. We test the MDP policy vs. current practice as well as against a number of other proposed policy changes.  相似文献   

7.
This paper considers whether gains made by shareholders from corporate takeovers are achieved at the expense of employees, as proposed by the ‘wealth transfer’ perspective. It analyses the contribution of employee lay‐offs, along with employment and wage changes, to the takeover premium and abnormal share price movements. The analysis draws on a unique dataset of British takeovers, combining documentary, share price and accounting data. The results show that lay‐offs planned at the takeover have either no effect or adverse effects on shareholder returns. Wages growth is positively, not inversely, related to shareholder returns from the second year after the takeover, whilst positive employment changes have a similar effect in the following year. Closer scrutiny indicates that labour and shareholders share gains when the firm does well, but share pain when it does not. There is evidence, therefore, that labour and shareholder interests can be complementary, rather than antagonistic, after takeovers.  相似文献   

8.
Two forms of single‐hit infection dose‐response models have previously been developed to assess available data from human feeding trials and estimate the norovirus dose‐response relationship. The mechanistic interpretations of these models include strong assumptions that warrant reconsideration: the first study includes an implicit assumption that there is no immunity to Norwalk virus among the specific study population, while the recent second study includes assumptions that such immunity could exist and that the nonimmune have no defensive barriers to prevent infection from exposure to just one virus. Both models addressed unmeasured virus aggregation in administered doses. In this work, the available data are reanalyzed using a generalization of the first model to explore these previous assumptions. It was hypothesized that concurrent estimation of an unmeasured degree of virus aggregation and important dose‐response parameters could lead to structural nonidentifiability of the model (i.e., that a diverse range of alternative mechanistic interpretations yield the same optimal fit), and this is demonstrated using the profile likelihood approach and by algebraic proof. It is also demonstrated that omission of an immunity parameter can artificially inflate the estimated degree of aggregation and falsely suggest high susceptibility among the nonimmune. The currently available data support the assumption of immunity within the specific study population, but provide only weak information about the degree of aggregation and susceptibility among the nonimmune. The probability of infection at low and moderate doses may be much lower than previously asserted, but more data from strategically designed dose‐response experiments are needed to provide adequate information.  相似文献   

9.
Journal of Management and Governance - An amendment to this paper has been published and can be accessed via the original article.  相似文献   

10.
This paper proposes a structural nonequilibrium model of initial responses to incomplete‐information games based on “level‐k” thinking, which describes behavior in many experiments with complete‐information games. We derive the model's implications in first‐ and second‐price auctions with general information structures, compare them to equilibrium and Eyster and Rabin's (2005) “cursed equilibrium,” and evaluate the model's potential to explain nonequilibrium bidding in auction experiments. The level‐k model generalizes many insights from equilibrium auction theory. It allows a unified explanation of the winner's curse in common‐value auctions and overbidding in those independent‐private‐value auctions without the uniform value distributions used in most experiments.  相似文献   

11.
This paper studies the effects of progressive income taxes and education finance in a dynamic heterogeneous‐agent economy. Such redistributive policies entail distortions to labor supply and savings, but also serve as partial substitutes for missing credit and insurance markets. The resulting tradeoffs for growth and efficiency are explored, both theoretically and quantitatively, in a model that yields complete analytical solutions. Progressive education finance always leads to higher income growth than taxes and transfers, but at the cost of lower insurance. Overall efficiency is assessed using a new measure that properly reflects aggregate resources and idiosyncratic risks but, unlike a standard social welfare function, does not reward equality per se. Simulations using empirical parameter estimates show that the efficiency costs and benefits of redistribution are generally of the same order of magnitude, resulting in plausible values for the optimal rates. Aggregate income and aggregate welfare provide only crude lower and upper bounds around the true efficiency tradeoff.  相似文献   

12.
The procurement of maintenance, repair, and operating (MRO) goods has remained a relatively understudied topic in the literature. Though vital cost efficiencies can be extracted from procurement processes through investments in e‐procurement systems, there is little empirical work that addresses how such systems should be deployed within organizations. In this study, we focus on the role of e‐procurement systems in MRO procurement and study two critical aspects of infusion. The first dimension captures the depth of e‐procurement use within the procurement function, while the second dimension depicts the breadth of use. We argue that these two dimensions of e‐procurement use, and their interaction, will be related to the performance of the MRO procurement process. Using survey data from 193 service organizations and structural equation modeling techniques, we show that the two infusion dimensions are significantly associated with improved process performance. Additionally, we show a substantial substitutive effect between the two use dimensions on performance. Our work has significant implications for managers who seek to gain efficiencies by the deployment of Internet‐based technologies within operational processes. Our conceptualization of e‐procurement infusion along two dimensions provides a more fine‐grained analysis of performance benefits accruing from the infusion of information technologies within organizations.  相似文献   

13.
The ongoing COVID‐19 pandemic is having a profound impact on organizations across the world, as businesses and societies face their greatest challenges for many decades. Over the past 20 years, the International Journal of Management Reviews (IJMR) has published many reviews of research that bring together the key findings across important bodies of research relevant to understanding how organizations might confront grand challenges such as these. Reflecting on this work, we have chosen a number of recent reviews published in the journal which have relevance both for practitioners and scholars in the current crisis. We invited the authors of these papers to offer some comments, which we have drawn from in the discussion below.  相似文献   

14.
15.
When firms evaluate their service system design choices, there is typically more uncertainty surrounding the value that a particular auxiliary service provides than there is on the cost of providing that service. To help inform this decision, we propose an approach where we compare the relative value of the segment of passengers who use an auxiliary service to the relative value of the segment that does not use it. We demonstrate this approach for a typical auxiliary service common to the airline industry. In 2008, most US airlines implemented checked baggage fee policies to decrease their costs by reducing the number of customer service agents needed in the check‐in and baggage handling processes. The success of this change has led to a current debate at many of these airlines on whether to make further staffing cuts in these areas, essentially making it even less attractive for passengers to check their baggage. Our proposed methodology helps answer whether passengers who continue to check bags in today's baggage‐fee era are more or less valuable than passengers who do not check bags. We explore this question empirically by examining, through a stated preference survey, if a history of checking or not checking bags can be used to segment passengers based on how their itinerary choices are influenced by common airline service attributes (on‐time performance, itinerary time, number of connections, airfare, and schedule delay). Contrary to the opinions of some top airline executives, we find that the passengers who continue to check bags at airlines that charge baggage fees are generally less sensitive to differences in three of these important service attributes and are less likely to switch airlines when a competing airline improves its offerings along these dimensions. Thus, airlines that charge for checked bags should consider improving the customer experience for their bag‐checking passengers, as they represent a potentially more valuable segment class to the airline.  相似文献   

16.
17.
This article illustrates how a traditional U.S. pharmaceutical industry supply chain operates, beginning with pharmaceutical compounds and ending at patient‐dispensing hospitals or pharmacies. Furthermore, to place the problem of U.S. drug shortages in historical perspective, a review of the annual volume of such shortages over the last decade is undertaken. Following this review of recent drug shortages is an analysis of the market forces and business decisions that drive the creation of a pharmaceutical gray market, its attendant “price gouging” and product integrity issues, and the alterations in the traditional pharmaceutical industry supply chain model. In response to persistent drug shortages, the U.S. Food and Drug Administration (FDA) has recently been empowered by the executive and legislative branches of the U.S. government to actively address this issue. To reflect these FDA challenges, a thorough review of these new agency charges and responsibilities is undertaken. Lastly, an analysis of the results of recent FDA public policy actions on mitigating drug shortages, as well as recommendations tor market‐based solutions to the gray market problem that pharmaceutical manufacturers, hospitals and pharmacies could institute as industry‐wide standards of business practice, are discussed in the conclusion.  相似文献   

18.
This study focuses on whether historical satisfaction with an e‐tailer (HSat) moderates baseline relationships in order fulfillment service quality models. HSat is defined as satisfaction with the e‐tailer spanning all transactions except the current encounter. Encounter satisfaction (ESat) is defined as the consumer's satisfaction with the current transaction. In the baseline model, four order fulfillment service quality (OFSQ) dimensions managerially relevant to consumer e‐tailing are examined: timeliness, availability, condition, and billing accuracy. The baseline structural model results support that OFSQ dimensions impact ESat, which in turn predicts two key consequences—repurchase intention and word‐of‐mouth. Adaptation theory is used to model the role of HSat, while controlling for transaction recency, vendor familiarity, and competitive pricing. HSat is shown to have pervasive main and interaction effects upon all baseline model relationships. These moderation effects have great managerial relevance. For example, the results illustrate a phenomenon similar to the service recovery paradox, wherein when a negative service encounter is followed by a highly positive service recovery event, previously dissatisfied consumers, as compared to previously satisfied consumers, respond with higher levels of current satisfaction. For managers, this finding is encouraging because policies that create highly positive events for consumers can thus supersede past negative experiences. Our results show however that HSat cannot be completely superseded by current OFSQ or current ESat.  相似文献   

19.
This article investigates potential differences in risk perception between experts (loss-prevention managers in the U.K. oil and gas production industry) and nonexperts (managers and students). Extant research on expert versus nonexpert perceptions of risk is reviewed, followed by the present study concerning risk perceptions of seven pen-picture scenarios involving the occurrence of hazardous events in the U.K. oil and gas production industry. In contrast to many of the earlier studies of expert versus nonexpert perceptions of risk, the present analysis concludes that experts did not judge the overall riskiness of the portrayed hazardous events as less risky than the nonexperts. Nevertheless, the experts believe more strongly than our nonexperts that the risks portrayed in the scenarios pose little threat to future generations, are more precisely known, and are relatively controllable. Use of multiple regression analysis to help uncover the basis of overall riskiness assessments for expert and lay respondents was inconclusive, however. Finally, little evidence was found that nonexperts were any more heterogeneous in their risk perceptions than experts. It may be that the nature of the risks assessed in the present study may account for the general lack of clear expert versus nonexpert differences in overall perceptions of the riskiness of hazardous events in the North Sea. Earlier findings of strong expert versus nonexpert differences in risk perception assessed hazards of major public concern. It is inferred that using such extreme hazards may have resulted in an exaggerated view of differences in expert versus public (nonexpert) perception of risk.  相似文献   

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