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In light of use by airline unions of partial-strike tactics, such as concerted refusals to bid for overtime work and so-called ” CHAOS” tactics involving unannounced refusals to fly after passengers have been ticketed and are ready to board, the authors examine whether the Railway Labor Act (RLA) should be interpreted to permit employers to discipline employees for engaging in such tactics, or whether these are a protected form of economic pressure. Although in many respects bargaining duties and economic weapons under the RLA are read consonant with precedents under the National Labor Relations Act (NLRA) (which governs all industries other than rail and air transport), there are a few decisions suggesting that during the period when self-help may be resorted to, employees can engage in partial strike activities as long as they violate no court order but are subject to permanent replacement in limited circumstances. These decisions, the authors submit, fail to take account of Supreme Court decsions since the 1930s that some economic pressures by unions, such as slowdowns and sitins, may not violate the labor laws but nor are they protected by those laws so as to immunize partial strikers from employer discipline. These decisions are not based on unique features of the NLRA. Rather, they give recognition to the background assumptions of Congress that employers may act to protect their property interests as long as they do not run afoul of NLRA or RLA protections and that employees who engage in partial-strike activities are subject to employer discipline even where not strictly necessary to maintain operations. Moreover, these tactics skew the bargaining process by giving employees an essentially risk-free gambit to pressure their economic position through planned disruption of carrier operations. Professor Estreicher is also labor and employment counsel to O’Melveny & Myers, LLP. The views expressed herein are the authors’ and should not be attributed to any organization. Hannah Breshin and Tom Jerman of O’Melveny & Myers, assisted the authors with this article. We also thank Professor Herbert Northrup for his helpful comments.  相似文献   
23.
Immigration has historically been associated with moral entrepreneurship and xenophobia. In periods of high unemployment and global dislocation, immigrants easily become the targets of political commentators who complain of their criminality, morals, demand on public services, and competition for scarce employment. In this exercise, looking at the recidivism of immigrants who come to Canada with a previous, foreign criminal history, quite a different picture emerges. Among this random sample (N=204), 97.5 percent of immigrants granted a rehabilitation waiver under the provisions of the Canadian Immigration Act were not re‐arrested in Canada within a period of about 3.5 years after their landing was approved by the Minister. Of those who were arrested, most of the delinquency was manageable and, in fact, resulted in either an acquittal, diversion or lower‐range sanctions. This is not the kind of imagery complained of by the tabloids or critics in the body politic. It behooves us, then, to exercise care in discussing crime and immigration, as it is a subject easily prone to the creation of “moral panics” and resulting repressive legislation against persons of color.  相似文献   
24.
We investigate wage differentials between ethnic groups in Israel, proposing a new methodology and an illustration based on the latest Israeli census. By using separate wage equations for the various occupations, our methodology allows us to decompose the wage differential into three components: one reflecting human capital differences; one reflecting wage discrimination; and a third indicating occupational segregation. We find that 70 percent of the wage gap is due to segregation, 26 percent to wage discrimination and only 4 percent to human capital differences. Evidence is also found for the existence of duality in the Israeli labor market.  相似文献   
25.
How are social networks organized and how much structure and openess do they have? The ambiguity of networking and the grade of organization are discussed and described theoretically and with an authentic example.  相似文献   
26.
This paper describes the design optimization of a robot sensor used for locating 3-D objects employing the Taguchi method in a computer simulation scenario. The location information from the sensor is to be utilized to control the movements of an industrial robot in a 'pick-and-place' or assembly operation. The Taguchi method, which is based on the Analysis-of-Variance (ANOVA) approach, is utilized to improve the performance of the sensor over a wider operating range. A review of the Taguchi method is presented along with step-by-step implementation details to identify and optimize the design parameters of the sensor. The method allows us to gauge the impact of various interactions present in the sensor system exclusively and permits us to single out those factors that have a dominant influence on the overall performance of the sensor. The investigation suggests that the Taguchi method is a more structured and efficient approach for achieving a robust design compared with the classical full factorial design approach.  相似文献   
27.
This paper outlines the conceptual bases, strategies, and psychological attributes of leadership by self-leadership. In addition, relations to other theories of leadership are drawn. Dimensions and correlates of self-leadership competence are described and discussed. Various approaches for developing self-leadership competence are discussed as well.  相似文献   
28.
Sets of relatively short time series arise in many situations. One aspect of their analysis may be the detection of outlying series. We examine the performance of standard normal outlier tests applied to the means, or to simple functions of the means, of AR(1) series, not necessarily of equal lengths. Although unequal lengths of series implies that the means have unequal variances, that are only known approximately, it is shown that nominal significance levels hold good under most circumstances. Thus a standard outlier test can usefully be applied, avoiding the complication of estimating the time series' parameters. The test's power is affected by unequal lengths, being higher when the slippage occurs in one of the longer series  相似文献   
29.
The last observation carried forward (LOCF) approach is commonly utilized to handle missing values in the primary analysis of clinical trials. However, recent evidence suggests that likelihood‐based analyses developed under the missing at random (MAR) framework are sensible alternatives. The objective of this study was to assess the Type I error rates from a likelihood‐based MAR approach – mixed‐model repeated measures (MMRM) – compared with LOCF when estimating treatment contrasts for mean change from baseline to endpoint (Δ). Data emulating neuropsychiatric clinical trials were simulated in a 4 × 4 factorial arrangement of scenarios, using four patterns of mean changes over time and four strategies for deleting data to generate subject dropout via an MAR mechanism. In data with no dropout, estimates of Δ and SEΔ from MMRM and LOCF were identical. In data with dropout, the Type I error rates (averaged across all scenarios) for MMRM and LOCF were 5.49% and 16.76%, respectively. In 11 of the 16 scenarios, the Type I error rate from MMRM was at least 1.00% closer to the expected rate of 5.00% than the corresponding rate from LOCF. In no scenario did LOCF yield a Type I error rate that was at least 1.00% closer to the expected rate than the corresponding rate from MMRM. The average estimate of SEΔ from MMRM was greater in data with dropout than in complete data, whereas the average estimate of SEΔ from LOCF was smaller in data with dropout than in complete data, suggesting that standard errors from MMRM better reflected the uncertainty in the data. The results from this investigation support those from previous studies, which found that MMRM provided reasonable control of Type I error even in the presence of MNAR missingness. No universally best approach to analysis of longitudinal data exists. However, likelihood‐based MAR approaches have been shown to perform well in a variety of situations and are a sensible alternative to the LOCF approach. MNAR methods can be used within a sensitivity analysis framework to test the potential presence and impact of MNAR data, thereby assessing robustness of results from an MAR method. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
30.
Empirical applications of poverty measurement often have to deal with a stochastic weighting variable such as household size. Within the framework of a bivariate distribution function defined over income and weight, I derive the limiting distributions of the decomposable poverty measures and of the ordinates of stochastic dominance curves. The poverty line is allowed to depend on the income distribution. It is shown how the results can be used to test hypotheses concerning changes in poverty. The inference procedures are briefly illustrated using Belgian data. An erratum to this article can be found at  相似文献   
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