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101.
102.
We re-evaluate Andreu and Spanos's findings in favour of trend stationarity by considering the extended Nelson-Plosser data set. This expanded (to 1988) data set includes a period of rather different behaviour compared with the original Nelson-Plosser data used by Andreou and Spanos. We find that Andreou and Spanos's models (with only minor adjustments) exhibit remarable stability over this extended period, and indicate that their conclusions are more robust than they have shown. 相似文献
103.
104.
Steven M. Ortiz 《Symbolic Interaction》2003,26(4):601-611
Using findings from a study of the world of the wives of professional athletes, this article explores the complex motivations for and displays of trust, rapport, and group acceptance during ethnographic research. Episodic exchanges between a male ethnographer and female collaborators revealed subtle issues of gender and perceived relative worth. This article proposes the outsider strategy of “muted masculinity” as a means of exploring ethnographic issues in which the boundaries between insiders and outsiders are uncertain. 相似文献
105.
Mohammad Salehi M. George A.F. Seber 《Australian & New Zealand Journal of Statistics》2004,46(3):483-494
Not having a variance estimator is a seriously weak point of a sampling design from a practical perspective. This paper provides unbiased variance estimators for several sampling designs based on inverse sampling, both with and without an adaptive component. It proposes a new design, which is called the general inverse sampling design, that avoids sampling an infeasibly large number of units. The paper provide estimators for this design as well as its adaptive modification. A simple artificial example is used to demonstrate the computations. The adaptive and non‐adaptive designs are compared using simulations based on real data sets. The results indicate that, for appropriate populations, the adaptive version can have a substantial variance reduction compared with the non‐adaptive version. Also, adaptive general inverse sampling with a limitation on the initial sample size has a greater variance reduction than without the limitation. 相似文献
106.
Using 1994 National Long Term Care Survey data, we estimated logistic regressions of formal and informal home health care use and hours. Home health care use and intensity were differentially impacted by chronic conditions, are higher for Medicaid enrollees and rural or small town residents, but lower for HMO enrollees. Decreases in the probability of home health care use increased informal instrumental activities of daily living (IADL) support four hours and decreased informal activities of daily living (ADL) support eight hours weekly. IADL caregiving substituted for formal care, but ADL caregiving declined with reductions in formal care. Public policy reducing formal home health care access may reduce informal ADL caregiving and increase informal IADL caregiving, producing net declines in support. 相似文献
107.
Jan C. H. van Eijkeren 《Risk analysis》2002,22(1):159-173
A mechanistic model is presented describing the clearance of a compound in a precision-cut liver slice that is incubated in a culture medium. The problem of estimating metabolic rate constants in PBPK models from liver slice experiments is discussed using identifiability analysis. From the identifiability problem analysis, it appears that in addition to the clearance, the compound's free fraction in the slice and the diffusion rate of the exchange of the compound between culture medium and liver slice should be identified. In addition, knowledge of the culture medium volume, the slice volume, the compound's free fraction, and octanol-water-based partition between medium and slice is presupposed. The formal solution for identification is discussed from the perspective of experimental practice. A formally necessary condition for identification is the sampling of parent compound in liver slice or culture medium. However, due to experimental limitations and errors, sampling the parent compound in the slice together with additional sampling of metabolite pooled from the medium and the slice is required for identification in practice. Moreover, it appears that identification results are unreliable when the value of the intrinsic clearance exceeds the value of the diffusion coefficient, a condition to be verified a posteriori. 相似文献
108.
Mr. Patrick J. Morrissette M.S.ED. 《Child and Adolescent Social Work Journal》1994,11(3):235-246
This paper proposes a developmental framework for foster parents and outlines four distinct growth stages. Such a framework can be of value to program administrators who are required to assess foster parent development during the crucial matching process. To draw a distinction between each developmental stage, specific instrumental tasks and indicators are outlined. 相似文献
109.
110.
Abstract This study examines the contentions of two recent perspectives on rural economic organization and their implications for poverty. Building from (1) agrarian political economy and (2) the rural restructuring literatures, we present a comparative regional analysis of how farming patterns and other aspects of economic organization differentially affect poverty in rural areas. Data are based on 2,349 nonmetropolitan U.S. counties for the 1970–1980 period. Nonhired labor-dependent, family-operated farming (smaller and larger family farming) has relatively similar cross-regional effects on rural poverty. The effects of industrialized farming are more spatially variant, suggesting that this type of farming is integrated into regional political economies in different ways than are simple commodity units. However, farming patterns have only a small effect on rural poverty relative to other factors, such as the local employment structure, characteristics of the population, and geographic location. The results of this study highlight the need to move beyond the farm sector to understand both the dynamics of this sector and the socioeconomic consequences of rural restructuring. More broadly, the study underscores the importance of testing general sociological relationships under different spatial (e.g., regional) contexts. 相似文献