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981.
The paper analyses the impact of foreign workers on the Italian labour market. We address the issue of whether immigrants from less developed countries are complementary or substitutes to domestic workers. We construct a data set on immigrant workers from the Administrative Social Security Archive which starts in 1986, before the general amnesty of 1990–91, when a large share of illegal immigrants were granted working permits, and end in 1995. A two-stage procedure devised by Moulton is applied to yearly cross-sections of wages by industry and region. Our results show that the inflow of immigrants raises the wages of native manual workers (i.e. it has a complementary effect), and this effect is larger in small firms and in the north of the country. We postulate that the positive impact on native wages is due to the existence of labour constraints on the side of firms. Firms are unable to expand their output because they cannot find native workers who are willing to undertake certain (typically low-skilled) jobs. Immigrants help to fill this gap. This view is reinforced by the fact that over a ‘crucial threshold’ of the share of foreign work (7.7–12 percent) additional inflows in the labour market of foreign work have a negative effect on native wages (i.e. they compete with natives).  相似文献   
982.
One of the cornerstones of any non-inferiority trial is the choice of the non-inferiority margin delta. This threshold of clinical relevance is very difficult to determine, and in practice, delta is often "negotiated" between the sponsor of the trial and the regulatory agencies. However, for patient reported, or more precisely patient observed outcomes, the patients' minimal clinically important difference (MCID) can be determined empirically by relating the treatment effect, for example, a change on a 100-mm visual analogue scale, to the patient's satisfaction with the change. This MCID can then be used to define delta. We used an anchor-based approach with non-parametric discriminant analysis and ROC analysis and a distribution-based approach with Norman's half standard deviation rule to determine delta in three examples endometriosis-related pelvic pain measured on a 100-mm visual analogue scale, facial acne measured by lesion counts, and hot flush counts. For each of these examples, all three methods yielded quite similar results. In two of the cases, the empirically derived MCIDs were smaller or similar of deltas used before in non-inferiority trials, and in the third case, the empirically derived MCID was used to derive a responder definition that was accepted by the FDA. In conclusion, for patient-observed endpoints, the delta can be derived empirically. In our view, this is a better approach than that of asking the clinician for a "nice round number" for delta, such as 10, 50%, π, e, or i.  相似文献   
983.
The nucleolus method has been suggested in the literature as a means for accounting decision makers to allocate joint costs in situations where entities share a common resource. The nucleolus has the advantage, vis-à-vis other methods, of maximizing the benefit to the least-well-off entity or groups of entities, and therefore reducing the possibility that one or more entities may desire to withdraw from the sharing arrangement. The nucleolus is basically a linear programming model. Because of its formulation, the nucleolus may yield multiple optimal solutions. No reformulation of the nucleolus seems to exist to overcome this problem The minimum total propensity to disrupt (MTPD) is suggested as an extension of the nucleolus to identify unique values for allocations with multiple solutions. The MTPD, while exhibiting deficiencies as a stand-alone method, is similar in overall objective to the nucleolus and its mathematical function possesses a unique minimum. It is therefore the logical method for identifying a unique nucleolus solution. The use of the MTPD extension is critically examined through a representative application.  相似文献   
984.
Paced assembly lines are widely used in repetitive manufacturing applications. Most previous research on the design of paced lines has assumed that each task along the line can be performed by only one worker (or a fixed number of workers). In many cases, however, task duration times may be reduced by increasing the number of workers or changing the equipment assigned to work stations. Thus, the problem becomes one of assigning resource alternatives (e.g., workers and/or equipment) and tasks to work stations to minimize total cost for a desired production rate. For this problem, we present three procedures. The first formulates the problem as a shortest path problem and guarantees optimality. The second and third are heuristic adaptations of the shortest path procedure that are capable of solving large problems. The procedures are compared in terms of solution quality and computation time on a set of 128 randomly generated problems for which optimal solutions could be found. Our simulation results indicate that the choice of procedure depends on problem complexity and resource costs.  相似文献   
985.
986.
Recent literature about sadomasochism in Sociology and Social Psychology is reviewed. Studies include survey research and questionnaire studies, content analyses, ethnographic research, and critical essays. The current state of our knowledge of sadomasochism, including its defining characteristics, sadomasochistic identities, and sadomasochistic subcultures is briefly summarized.  相似文献   
987.
This paper describes a structured methodology for decomposing the conceptual design problem in order to facilitate the design process and result in improved conceptual designs that better satisfy the original customer requirements. The axiomatic decomposition for conceptual design method combines Alexander's network partitioning formulation of the design problem with Suh's Independence Axiom. The axiomatic decomposition method uses a cross‐domain approach in a House of Quality context to estimate the interactions among the functional requirements that are derived from a qualitative assessment of customer requirements. These interactions are used in several objective functions that serve as criteria for decomposing the design network. A new network partitioning algorithm is effective in creating partitions that maximize the within‐partition interactions and minimize the between‐partition interactions with appropriate weightings. The viability, usability, and value of the axiomatic decomposition method were examined through analytic comparisons and qualitative assessments of its application. The new method was examined using students in engineering design capstone courses and it was found to be useable and did produce better product designs that met the customer requirements. The student‐based assessment revealed that the process would be more effective with individuals having design experience. In a subsequent assessment with practicing industrial designers, it was found that the new method did facilitate the development of better designs. An important observation was the need for limits on partition size (maximum of four functional requirements.) Another issue identified for future research was the need for a means to identify the appropriate starting partition for initiating the design.  相似文献   
988.
This article uses the Deming management model developed by Anderson et al. (1994b) as an initial template to analyze total quality in services. While the literatures addressing quality management have developed separately for products and services, the founders of total quality portrayed this management philosophy as universally oriented. Our study first replicates two earlier studies that tested the Deming management model in manufacturing industries. Using hospitals as our unit of analysis, we realized findings similar to the earlier manufacturing studies. Next, we used contributions from the MBNQA literature to test an enhanced model. Our subsequent findings support the MBNQA concept that “leadership drives the system that creates results” and provides evidence of the ubiquitous importance of leadership for ensuring the success of a quality improvement program. Finally, an anomaly of this study and those published earlier is the inability to find support for the relationship between continuous improvement and customer satisfaction. Integrating the substantial work in the service quality literature focused on customer satisfaction measurement is recommended to future researchers to help resolve this issue and further enhance the model.  相似文献   
989.
Uses and gratifications (U&G) is a media use paradigm from mass communications research that guides the assessment of consumer motivations for media usage and access. It has been used previously in research and decision making related to the promotion of emerging radio and television media. Recent adaptations of U&G research to the Internet are incomplete and have not identified important new Internet‐specific gratifications. This paper empirically derives dimensions of consumer Internet use and usage gratifications among customers of a prominent Internet Service Provider (ISP). Results describe three key dimensions related to consumer use of the Internet, including process and content gratifications as previously found in studies of television, as well as an entirely new social gratification that is unique to Internet use. All three dimensions of gratification are relevant to managing the Internet as a commercial medium, and measures developed from the gratification profiles identified here can serve as trait‐valid scales in future Internet and e‐commerce research.  相似文献   
990.
Capital tax competition is known to result in inefficiently low tax rates and an undersupply of public goods. The provision of public goods and with it the welfare of all countries can be enhanced via tax coordination. Based on the standard Zodrow-Mieszkowski-Wilson tax-competition model this paper analyzes the conditions under which tax coordination by a group of countries is self-enforcing. In our analytical framework, there always exists a rather small stable tax coalition. For some subset of the parameter space the grand coalition is stable, even if the total number of countries is large. If the stable coalition is small, it is not very effective in mitigating the inefficiency of the non-cooperative Nash equilibrium. The ineffectiveness is increasing in the total number of countries.  相似文献   
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