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971.
Nine macroeconomic variables are forecast in a real-time scenario using a variety of flexible specification, fixed specification, linear, and nonlinear econometric models. All models are allowed to evolve through time, and our analysis focuses on model selection and performance. In the context of real-time forecasts, flexible specification models (including linear autoregressive models with exogenous variables and nonlinear artificial neural networks) appear to offer a useful and viable alternative to less flexible fixed specification linear models for a subset of the economic variables which we examine, particularly at forecast horizons greater than 1-step ahead. We speculate that one reason for this result is that the economy is evolving (rather slowly) over time. This feature cannot easily be captured by fixed specification linear models, however, and manifests itself in the form of evolving coefficient estimates. We also provide additional evidence supporting the claim that models which ‘win’ based on one model selection criterion (say a squared error measure) do not necessarily win when an alternative selection criterion is used (say a confusion rate measure), thus highlighting the importance of the particular cost function which is used by forecasters and ‘end-users’ to evaluate their models. A wide variety of different model selection criteria and statistical tests are used to illustrate our findings.  相似文献   
972.
A dialectical relationship exists between the capitalist desire for accumulation of wealth and profits, and the rights of employees. Labor process theory exposes facets of the fundamental incongruity between the interests of employers and workers in a capitalist political economy. An analysis of employee rights through the labor process framework facilitates the potential for human emancipation by illuminating the ideological, political, and economic sources of domination and repression that are embedded in the capitalist system. In this article, three core elements of labor process theory—the social relations of production, the managerial control imperative, and the restructuring of work—are used to highlight ways in which organizations maintain their hegemonic position. This exposé offers the basis for an alternative paradigmatic view of the employment relationship and informs our thinking of how employee rights are impacted, and often tempered, in work organizations. Portions of this article were presented by both authors at the 12th Annual International Labour Process Conference March, 1994 in Birmingham, England.  相似文献   
973.
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.

This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students.  相似文献   

974.
    
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975.
This paper develops a rational expectations framework for interpreting the coefficient on age in a standard hedonic model. The model demonstrates that there are two components to the age coefficient: a pure cross-sectional depreciation component and a demand-side component that changes over time. We also show that a constant quality price index with age constant can be estimated by using any repeat sales database that contains the year of construction (or property age). When Fairfax County data are fitted to the model, the time series of age coefficients is non-stationary: they change from negative in the early 1980s to positive in the late 1980s; we infer that the demand-side component dominated in the latter period.  相似文献   
976.
977.
A strategic human resource perspective of firm competitive behavior   总被引:1,自引:0,他引:1  
Embedded within firms are unique stores of intangible human assets that likely influence the way firms compete. We argue that the human and social capital of a firm, particularly at the upper echelon and board of director (BOD) levels, contribute to the firm's awareness of the competitive environment and its motivation and ability to undertake numerous, complex, and forceful competitive actions. We also suggest that the firm's executive compensation systems moderate the effects of these intangible human assets on firm competitive behavior. By examining how human capital, intra-firm social capital, and executive compensation influence firm competitive behavior, we advance a strategic HRM perspective of firm competitive behavior and outline several implications for future research.  相似文献   
978.
979.
This paper examines 2 years of data from GEM Canada in order to develop new insights into the factors that contribute to the performance outcomes of female enterprises and how these factors are affected by the firm’s stage of development. The analysis encompasses both personal and organizational characteristics and assesses their association with selected performance measures at the early stage as well as at the established phase of development. The findings indicate that the greater propensity of men to pursue business growth and earnings can be attributed to marital status (live with a partner) and the expected depth of the ownership team. Moreover, the performance outcomes for male entrepreneurs are influenced by a relatively wide range of variables, with business demographics being more prominent than for the female enterprises. For both genders, the mix of relevant underlying factors varies as the venture progresses along the ‘nascent-new-established’ continuum.  相似文献   
980.
In order to explain coexistence of a deductible for low values of the loss and an upper limit for high values of the loss in insurance contracts, we consider the exchange of risk between two rank dependent expected utility maximizers. It is shown that if the insurer (insured) takes more into account the lowest outcomes – hence maximal losses – than the insured (insurer), then the optimal contract has an upper limit (includes a deductible for high values of the loss). If furthermore, the insured (insurer) neglects the highest outcomes while the insurer (insured) does not, the optimal contract includes a deductible (full insurance) for low values of the loss.  相似文献   
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