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排序方式: 共有521条查询结果,搜索用时 13 毫秒
1.
The purpose of this study was to identify relevant factors associated with the noncustodial father's frequency of contact with his child following divorce. The findings of the research revealed that a combination of demographic, personal characteristics, and psychosocial factors are related to the father's frequency of contact with the child.  相似文献   
2.
The objective of this paper is to introduce the Wiener-Kolmogorov (WK) method to business researchers and to applied workers who have an interest in spectral techniques. It is seen that the advantage of the WK method is that it provides better forecasts than autoregressive regression analysis when the order of the true autoregressive process is large. The paper outlines the steps involved in the WK method. Also discussed is a labor-saving feature to guide one at the outset as to whether the WK algorithm should be used. A numerical example is given to illustrate the application of the method in time-series forecasting.  相似文献   
3.
A Diamond-Stiglitz approach to the demand for self-protection   总被引:1,自引:0,他引:1  
The existing research concerning the relationship between risk aversion and prudence and the demand for self-protection assumes that the loss variable follows a Bernoulli distribution, and that changes in the level of self-protection are mean preserving. The analysis here replaces these two very strong conditions with ones which are more general. When doing this, the method of analysis is also significantly modified. This modification includes representing a change in the level of self-protection using the procedure developed by Diamond and Stiglitz (Journal of Economic Theory 8:337-360, 1974) for representing a change in risk. This alternate representation allows the existing findings to be generalized considerably, and also simplifies the analysis.  相似文献   
4.
The hypothesis testing and confidence region are considered for the common mean vector of several multivariate normal populations when the covariance matrices are unknown and possibly unequal. A generalized confidence region is derived using the concepts of generalized method based on the generalized pp-value. The generalized confidence region is illustrated with two numerical examples. The merits of the proposed method are numerically compared with those of existing methods with respect to their expected area or expected d-dimensional volumes and coverage probabilities under different scenarios.  相似文献   
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6.
In this paper, we consider a Bayesian analysis of the unbalanced (general) growth curve model with AR(1) autoregressive dependence, while applying the Box-Cox power transformations. We propose exact, simple and Markov chain Monte Carlo approximate parameter estimation and prediction of future values. Numerical results are illustrated with real and simulated data.  相似文献   
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8.
Places affected or threatened by extreme environmental disturbances confront a number of significant issues, including whether their populations will stay the same or change through migration. Research on Hurricanes Katrina and Rita shows some displaced residents returned to their disaster-affected communities once the built environment was restored, new migrants settled in affected places as part of the rebuilding effort, and the regional migration system grew more urbanized and spatially concentrated during post-disaster years. Research also shows that not all disaster-affected places recovered their populations. Our study examines whether differential recovery is systematically patterned along the rural–urban gradient. Using U.S. Census Bureau estimates and IRS county-to-county migration data, we investigate whether the 2005 hurricane season differentially exacerbated or altered previous migration trends across a rural–urban gradient that incorporates proximity to metropolitan areas and disaster-related housing loss. We find a rural–urban differential in Gulf Coast recovery migration: The disaster boosted migration among non-metropolitan counties, yet these increases were smaller and short-lived compared to the patterns found for metropolitan counties, most especially high loss metropolitan counties. Our findings encourage theories of environmental migration to incorporate spatial differentiation and scenarios of environmental changes to account for differential impacts on settlement patterns across the rural–urban continuum.  相似文献   
9.
The advent of the wide variety of new, highly integrated, advanced manufacturing technologies available for acquisition by a firm's managers has brought to light an accompanying set of unexpected issues. These issues include expectations for the benefits and costs of these technologies, determining the appropriate order of implementation and finding a way to justify acquisition when many of the benefits are a function of the technology's learning and synergistic effects on other operations and technologies. We present here a model that captures the interaction effects of these highly integrated technologies and discuss the data requirements for application of the construct. We then illustrate the model's workings with a number of multitechnology examples and show the danger of ignoring the synergistic and learning effects of these technologies when considering their acquisition.  相似文献   
10.
Diversification gains in mean-variance efficiency derived from including real estate in financial asset portfolios are examined. Optimal financial and mixed-asset portfolios were generated by selecting from an investment universe including several distinct financial and real estate media. Deficiencies of previous studies were overcome by employing data with improved representativeness and comparability. The efficient mixed-asset portfolios dominated the efficient financial asset portfolios implying that purely financial asset diversification is inefficient. The optimal mixed-asset portfolio prescribed that approximately two-thirds of the investment wealth be allocated to real estate and one-third to the financial media.  相似文献   
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