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271.
Objectives. The primary goal of this article is to examine factors associated with grandparent care giving within the American Indian/Alaska Native (AIAN) population. Methods. Data from the 2000 Census of Population, 5% Public Use Microdata Sample, are used to evaluate a multivariate logistic regression model focusing on living with and caring for grandchildren. Particular emphasis is placed on characteristics that may reflect culturally‐based ideas about grandparents' responsibility for the care of their grandchildren. Results. Indicators related to Native‐American identity—specifically, reporting race as AIAN only rather than mixed race, reporting tribal membership, and living in a nonmetropolitan area of an “Indian” state—increase the likelihood of being responsible for a grandchild among Native‐American singles and couples aged 45 and over. Conclusions. Cultural and resource characteristics combine to produce high levels of grandparent care giving within the AIAN population. Inasmuch as those with lower educational and economic resources are especially likely to have responsibility for a grandchild, special attention should be directed toward ensuring adequate support for these caregivers. 相似文献
272.
Two Bayes-type procedures for estimating a multinomial cell probabilities vector, P, in the presence of linear constraints on the parameters are proposed and illustrated by examples from contingency table analysis. Estimation under log-linear constraints is also considered. 相似文献
273.
Van Leeuwen JM Boyle S Salomonsen-Sautel S Baker DN Garcia JT Hoffman A Hopfer CJ 《Child welfare》2006,85(2):151-170
This article reports on results of a one-day public health survey conducted in six states by homeless youth providers to measure and compare risk factors between lesbian, gay, and bisexual (LGB) homeless youth and non-LGB homeless youth. This article intends to inform the child welfare field on existing gaps in services and areas where more training and technical support is necessary in providing services to homeless LGB youth. The findings point to substantial differences within the homeless youth sample and demonstrate that in addition to the public health risks young people face merely by being homeless, the risks are exacerbated for those who self-identify as lesbian, gay, or bisexual. The article informs child welfare providers and policymakers about the substantial vulnerability of LGB youth beyond that of non-LGB homeless youth and the need to fund programming, training, technical assistance and further research to specifically respond to the complex needs of this population. 相似文献
274.
Revenue Management Systems (RMS) are commonly used in the hotel industry to maximize revenues in the short term. The forecasting‐allocation module is a key tactical component of a hotel RMS. Forecasting involves estimating demand for service packages across all stayover nights in a planning horizon. A service package is a unique combination of physical room, amenities, room price, and advance purchase restrictions. Allocation involves parsing the room inventory among these service packages to maximize revenues. Previous research and existing revenue management systems assume the demand for a service package to be independent of which service packages are available for sale. We develop a new forecasting‐allocation approach that explicitly accounts for this dependence. We compare the performance of the new approach against a baseline approach using a realistic hotel RMS simulation. The baseline approach reflects previous research and existing industry practice. The new approach produces an average revenue increase of at least 16% across scenarios that reflect existing industry conditions. 相似文献
275.
Intergenerational social mobility studies have largely explored the relationship between one aspect of parent background (e.g., education, income, occupational status, wealth, or neighborhood context) and the corresponding aspect of that parent's child once they reach adulthood. Studies examining these various measures have provided differing conclusions about the extent that social origins constrain attainment in the U.S. In contrast, the persistence of racial inequality in intergenerational mobility is one consistent finding. For instance, across various measures, research demonstrates Black individuals are more likely than White individuals to experience downward mobility, and less likely to exceed the socioeconomic standings of their parents. In this article, we argue that a more holistic measure of both origin and destination, one that combines the above-mentioned indicators, is necessary to advance our understanding of the extent that origin constrains future attainment. We summarize lessons gleaned from one-dimensional estimates, and from other approaches that either combine some dimensions of socioeconomic background or attempt to capture a more holistic background in other ways. We then make a recommendation for methodological interventions to accomplish this more holistic approach and conclude with research and policy implications. 相似文献
276.
Yield management is the dynamic pricing, overbooking, and allocation of perishable assets across market segments in an effort to maximize short-term revenues for the firm. Numerous optimization heuristics for allocation and overbooking exist for the airline industry, whose perishable asset is the airplane seat. When an airplane departs, no revenue is gained from the empty seat(s). In the hotel industry, the perishable asset is the hotel room-once a room is left empty for a night, that night's revenue cannot be recaptured. The literature on yield management heuristics for the hotel industry is sparse. For the hotel operating environment, no research has adequately (1) integrated overbooking with allocation, (2) modeled the phenomenon of hotel patrons extending or contracting their stay at a moment's notice, or (3) performed a realistic performance comparison of alternative heuristics. This research develops (1) two hotel-specific algorithms that both integrate overbooking with the allocation decisions, (2) a simulation model to reproduce realistic hotel operating environments, and (3) compares the performance of five heuristics under 36 realistic hotel operating environments. Seven conclusions are reached with regard to which heuristic(s) perform best in specific operating environments. Generally, heuristic selection is very much dependent on the hotel operating environment. A counterintuitive result is that in many operating environments, the simpler heuristics work as well as the more complex ones. 相似文献
277.
278.
Early in the pandemic of coronavirus disease 2019 (COVID-19), face masks were used extensively by the general public in several Asian countries. The lower transmission rate of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Asian countries compared with Western countries suggested that the wider community use of face masks has the potential to decrease transmission of SARS-CoV-2. A risk assessment model named Susceptible, Exposed, Infectious, Recovered (SEIR) model is used to quantitatively evaluate the potential impact of community face masks on SARS-CoV-2 reproduction number (R0) and peak number of infectious persons. For a simulated population of one million, the model showed a reduction in R0 of 49% and 50% when 60% and 80% of the population wore masks, respectively. Moreover, we present a modified model that considers the effect of mask-wearing after community vaccination. Interestingly mask-wearing still provided a considerable benefit in lowering the number of infectious individuals. The results of this research are expected to help public health officials in making prompt decisions involving resource allocation and crafting legislation. 相似文献
279.
A major issue in value-function assessment is the possibility of receiving an indefinite response from a decision maker to a question about preferences. The conventional treatment requires a single, definite response from the decision maker. This approach either assumes that response error is zero or accepts the final solution as only approximate, without knowing how approximate it might be. In this paper we examine the issue of indefinite responses, define it more precisely, and present a method for incorporating it into decision making. The method is adaptive in that it is iterative and interactive with the decision maker who, at each iteration, is provided with information regarding the potential advantage of answering more trade-off questions and/or answering questions more carefully to reduce response error. In contrast to other approaches that “force” rationality and decisiveness, we work with irrationality and indecisiveness on the part of the decision maker. The method is demonstrated for the case of concave, increasing value functions. 相似文献