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991.
The influence of competition level on referees’ decision-making was investigated. Referees’ decisions in 90 handball games (30 games X 3 competition levels) were observed in different situations related to the advantage rule, and 100 referees from two different levels of expertise were subsequently asked to offer explanations for the competition-level effects from the first part of the study. Results revealed that at the highest level of competition referees intervened less frequently with sporting sanctions, but more frequently with disciplinary sanctions. These effects were apparent mainly in immediate intervention situations and unsuccessful advantage situations, but not in successful situations. Referees explained these effects of competition level in terms of a player competence stereotype, in addition to referees’ different expertise across competition level. The implications of the findings for understanding how status-related stereotypes impact on intervention behavior are discussed.  相似文献   
992.
Most previous studies of income inequality have either ignored capital gains or have used taxable realized capital gains to estimate top incomes. Neither of these approaches is fully satisfactory. We apply for the first time a new methodology that allows us to account for fundamental accrued capital gains as part of the top incomes in a theoretically consistent manner. We estimate the shares of the super-rich in Chile showing that accrued capital gains have a large impact on these estimates. Also, the top income shares estimated using fundamental capital gains appear to exhibit a more stable and presumably more plausible time profile than estimates based on capital gains derived from asset market variations.  相似文献   
993.
When immigrants enter the US they typically access a marriage market with a larger supply of educated spouses compared to the marriage market in their home countries. Absent any selectivity bias, this access should increase the likelihood that migrants ‘marry-up’ in terms of education. We combine survey data on British and German immigrants in the US with data on natives in Britain and Germany to estimate the causal effect of migration on educational mobility through cross-national marriage. To control for selective mating, we instrument educational attainment using government spending on education in the years each person was of school-age. To control for selective migration, we instrument the migration decision using inflows of immigrants to the US during puberty and early adulthood. We find strong selectivity effects that work against the positive prospects of the US marriage market. All migrants give up spousal education in exchange for US entry and assimilation. Migrant men also give up spousal education because they cannot compete with native men as bread-earners. Migrant women have some advantage in the US marriage market, as they can compete with native women in home production.  相似文献   
994.

Background

Real-world fall events objectively measured by body-worn sensors can improve the understanding of fall events in older people. However, these events are rare and hence challenging to capture. Therefore, the FARSEEING (FAll Repository for the design of Smart and sElf-adaptive Environments prolonging Independent livinG) consortium and associated partners started to build up a meta-database of real-world falls.

Results

Between January 2012 and December 2015 more than 300 real-world fall events have been recorded. This is currently the largest collection of real-world fall data recorded with inertial sensors. A signal processing and fall verification procedure has been developed and applied to the data. Since the end of 2015, 208 verified real-world fall events are available for analyses. The fall events have been recorded within several studies, with different methods, and in different populations. All sensor signals include at least accelerometer measurements and 58 % additionally include gyroscope and magnetometer measurements. The collection of data is ongoing and open to further partners contributing with fall signals. The FARSEEING consortium also aims to share the collected real-world falls data with other researchers on request.

Conclusions

The FARSEEING meta-database will help to improve the understanding of falls and enable new approaches in fall risk assessment, fall prevention, and fall detection in both aging and disease.
  相似文献   
995.
The present study uses canonical analysis to examine the contingency model of organizations in the nursing home field. Data on environmental pressures and managerial practices relevant to the decision-making process are analyzed. Results support the theory that managerial practices are contingent on environmental pressures. The implications of these results for health-care decision makers and for future assessments of managerial-environmental relationships are discussed.  相似文献   
996.
Under conditions of degeneracy, sensitivity analysis information such as cost and right-hand-side ranges, which are produced by standard linear programming procedures used in commercial codes, can be misleading. From a managerial perspective, the interpretation of such information can be erroneous. In this paper we present these problems, explain their occurence with elementary examples, and discuss procedures for their resolution.  相似文献   
997.
This paper examines forecast error with an intention not to minimize forecast error so much as to bias the resultant error in order to achieve better managerial results. Much work has been accomplished by other researchers toward the goal of minimizing forecast error—sometimes by the use of sophisticated forecasting techniques. The results of this paper indicate that manipulating forecast error bias may be the better managerial strategy as opposed to going to great lengths to minimize forecast error. Subject Areas: Forecasting, Aggregate Planning, Capacity Planning, and Production/Operations Management.  相似文献   
998.
We investigate the performance of capacity-sensitive order review and release (ORR) procedures in job shop environments that have not been previously explored. Previous research has ignored the case of job shops which must perform to very tight due-dates because of time-sensitive customers. We propose and test a new capacity sensitive ORR procedure called path based bottleneck (PBB) in such environments, along with the modified infinite loading (MIL) procedure which has been shown to work well in several studies. We compare the performance of these two controlled release rules with that of immediate release rule under different conditions of capacity utilization and customer specified exogenous duedates. Our results indicate that PBB performs well in lowering total costs when due-dates are tight, while MIL is a better procedure with relatively loose to medium due-dates. We also show that in many cases, the shortest processing time (SPT) dispatching rule is a superior performer than a due-date based rule like critical ratio (CR); a conclusion which is contrary to the existing research in this area. In addition, the shop floor control policies recommended are shown to be sensitive to the cost structure of the firm. The managerial implications of this research in providing effective shop floor control in job shops operating under tight due-date conditions are also discussed.  相似文献   
999.
This study investigates the impact of worker learning, worker flexibility, and labor attrition on the system performance of a dual resource constrained (DRC) job-shop. The effects of learning and labor attrition have not been previously addressed in DRC literature. Results from the study, consistent with previous literature, show that the greatest benefits are achieved when inter-departmental worker flexibility is incrementally introduced into the system. In addition, the learning environment, which depends on the initial processing time of jobs and the learning rates of workers, is shown to impact the acquisition of flexibility. The study also shows that the impact of labor attrition on system performance under certain shop conditions may be significant.  相似文献   
1000.
We examine the phenomenon of shifting production bottlenecks from an analytic perspective. We quantify the propensity of a work center to be a bottleneck, defined as maximal queue length, using a simple Jackson production network model. Comparison of the analytic model against an empirical simulation-based model shows that the two are in good agreement. A scalar measure of bottleneck shiftiness is proposed and used to investigate several policies for mitigating shiftiness. Simulation experiments show that several commonly observed managerial policies for coping with shifting bottlenecks actually increase shiftiness, but that shiftiness declines when the capacity of nonbottleneck resources is increased.  相似文献   
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