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101.
It is commonly assumed that contractors are largely calculative, instrumental and self-interested in their relationship with organizations and interface with them accordingly (e.g. low corporate interest and emotional investment). This paper describes a survey involving 117 contractors (62 on 'permanent' agency contracts and 55 on 'temporary' agency contracts) and a comparable (age, job level/grade, years of work experience) group of 86 direct employees (on fixed-term contracts). The survey comprised measures of the psychological contract, of organizational identification, social (corporate) attraction, team spirit and intention to leave. The findings show that contractors are not inevitably 'emotionally' detached from their place of work, in some cases investing in it as much as direct company employees. While transactional (e.g. financial gain, instrumentality) exchange considerations were more salient among contractors than employees, this did not appear to preclude the development of a relational (e.g. corporate integration and long-term investment) contractual orientation. 'Team spirit' and 'organizational identification' predicted the development of relational contracts over and above contractual status. The findings and their management implications are discussed in terms of 'strategic partnership'. 相似文献
102.
Examining the relationship between the competitive processes between and within organizations, we use selection system theory to link resource value to product value. We identify three dimensions (in‐selection, before‐selection and after‐selection) that facilitate determining the value of resources based on the functions they serve in the competitive process between organizations in the product market, i.e. the external selection system. Subsequently, we use these dimensions to explore the competitive process among resource providers within organizations, i.e. the internal selection system. This leads us to formulate three propositions that link the competitive process within organizations to the competitive process between organizations. First, we posit that if resources that individually score highly along only one of the three dimensions are bundled, it is more likely that organizational performance can be sustained. Second, we argue that providers of resources scoring highly along multiple dimensions will enjoy stronger means of appropriation in comparison with providers of resources scoring highly along only one of the three dimensions. Third, we contend that the extent to which an organization endeavours to remunerate its resource providers based on their perceived contribution to the organization's competitive position has a curvilinear (inverted U‐shaped) relationship with organizational performance. 相似文献
103.
Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System. 相似文献
104.
Christopher R. Kirman Sean M. Hays Gregory L. Kedderis Michael L. Gargas & Dale E. Strother 《Risk analysis》2000,20(1):135-152
Historically, U.S. regulators have derived cancer slope factors by using applied dose and tumor response data from a single key bioassay or by averaging the cancer slope factors of several key bioassays. Recent changes in U.S. Environmental Protection Agency (EPA) guidelines for cancer risk assessment have acknowledged the value of better use of mechanistic data and better dose–response characterization. However, agency guidelines may benefit from additional considerations presented in this paper. An exploratory study was conducted by using rat brain tumor data for acrylonitrile (AN) to investigate the use of physiologically based pharmacokinetic (PBPK) modeling along with pooling of dose–response data across routes of exposure as a means for improving carcinogen risk assessment methods. In this study, two contrasting assessments were conducted for AN-induced brain tumors in the rat on the basis of (1) the EPA's approach, the dose–response relationship was characterized by using administered dose/concentration for each of the key studies assessed individually; and (2) an analysis of the pooled data, the dose–response relationship was characterized by using PBPK-derived internal dose measures for a combined database of ten bioassays. The cancer potencies predicted for AN by the contrasting assessments are remarkably different (i.e., risk-specific doses differ by as much as two to four orders of magnitude), with the pooled data assessments yielding lower values. This result suggests that current carcinogen risk assessment practices overestimate AN cancer potency. This methodology should be equally applicable to other data-rich chemicals in identifying (1) a useful dose measure, (2) an appropriate dose–response model, (3) an acceptable point of departure, and (4) an appropriate method of extrapolation from the range of observation to the range of prediction when a chemical's mode of action remains uncertain. 相似文献
105.
Social interaction, particularly in older adolescents, increasingly involves computer‐mediated communication. Although studies of public computer‐mediated communication are increasingly common, studies of private text messaging remain rare. As approaches for obtaining such data evolve with technological advances, developmental scientists need designs in which to use such approaches that reduce sampling biases in both participants and text messages. In this study (n = 854; 46% male; 22% African American, 60% European American), we examined selection biases in the participant sample (i.e., factors associated with actual participation), procedural biases in the participant sample (i.e., factors related to failed data capture due to technological or procedural issues), and selection biases in the sample of text messages (i.e., based on self‐reported reasons for texting). Findings from our study suggest that studying human interaction directly through analysis of text message data is not only feasible, but also may be successfully undertaken with minimal biases regarding sample selection and text message selection among those who are engaged in research and engaged in text messaging outside of the study context. However, biases may occur depending on the type of platform (iPhone vs. Android) used by participants for texting. 相似文献
106.
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108.
今天,日益增长的全球资本主义经济是一张复杂的动态的网络,这个网络由社会、文化以及反映我们个人和大众的意识的经济体制构成。随着意识创造并联结了所有事物这一观点被人们日渐认可,以及全球责任感的增强,资本主义经济体制可以切实地被改变,从而促进经济的长期繁荣。 相似文献
109.
Pulier (2000, Theory and Decision 49: 291) and Machina (2000, Theory and Decision 49: 293) seek to dissolve the Barrett–Arntzenius infinite decision puzzle (1999, Theory and Decision 46: 101). The proposed dissolutions, however, are based on misunderstandings concerning how the puzzle works and the nature of supertasks more generally. We will describe the puzzle in a simplified form, address the recent misunderstandings, and describe possible morals for decision theory. 相似文献
110.
Our “Restated diversification theorem” (Skogh and Wu, 2005) says that risk-averse agents may pool risks efficiently without assignment of subjective probabilities to outcomes, also at genuine uncertainty. It suffices that the agents presume that they face equal risks. Here, the theorem is tested in an experiment where the probability of loss, and the information about this probability, varies. The result supports our theorem. Moreover, it tentatively supports an evolutionary theory of the insurance industry—starting with mutual pooling at uncertainty, turning into insurance priced ex ante when actuarial information is available. 相似文献