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21.
Informal caregivers of individuals with Alzheimer's disease spend a considerable amount of time providing care. In this paper, we use Grossman's health production and Becker's time allocation models to develop a model of informal care provision to elderly dementia patients. In our model, time inputs produce caregiving services, which provides utility to the caregiver, but reduces leisure. We assume that time is less productive of services on the margin as the disease progresses. In this framework, an increase in patients' disease severity does not necessarily increase informal caregiver time input. The cost of formal care establishes a reservation price for informal caregiving. When the costs of informal caregiving rise above this reservation level, the patient is institutionalized. We test empirically the effect of deterioration in the patients' condition, proxied by both disease severity and dementia problem behavior, on informal caregiving time. We find that dementia-related problem behaviors and functional limitations significantly increase inputs of informal caregiving time. Patients' problem behavior exerts a modifying effect on functional limitations, and patients' comorbidities have no effect on informal caregiving time.  相似文献   
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Diagnostics for dependence within time series extremes   总被引:1,自引:0,他引:1  
Summary. The analysis of extreme values within a stationary time series entails various assumptions concerning its long- and short-range dependence. We present a range of new diagnostic tools for assessing whether these assumptions are appropriate and for identifying structure within extreme events. These tools are based on tail characteristics of joint survivor functions but can be implemented by using existing estimation methods for extremes of univariate independent and identically distributed variables. Our diagnostic aids are illustrated through theoretical examples, simulation studies and by application to rainfall and exchange rate data. On the basis of these diagnostics we can explain characteristics that are found in the observed extreme events of these series and also gain insight into the properties of events that are more extreme than those observed.  相似文献   
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Conclusion Throughout American history, first on the family farm and now in modern day business institutions, the workplace has been a stabilizing institution in American society that has anchored the ongoing, informal interactions occurring outside the workplace. In 1900, few Americans had a private mode of transportation. Barely 4,000 passenger automobiles were sold in 1900, and while horses were common, they were used primarily for farming, public transportation, and commercial activity in cities. By 1930, nearly 40 million cars had been added to America’s streets. The automobile recast life and work in central cities and eventually the suburbs.  相似文献   
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In our zeal to deal with alcohol and drug abuse, we may have a distorted picture of what the majority of college students actually think about alcohol and drug use. Students in this study done at a public university located in the Deep South report being generally intolerant of substance abuse.  相似文献   
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This paper discusses some uses in econometrics of empirical process theory for dependent rendom variables. Examples considered include non-standard parametric hypotheses tests and semiparametric estimation. The application of bracketing functional limit results is discussed in some detail  相似文献   
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The more things change, the worse they get.Presented April 18, 1991, Duke University, at the Department of Psychiatry's Grand Rounds, this paper condenses, integrates and updates the author's earlier publication. Acknowledgement and thanks for funding and professional sponsorship of the four research studies this paper draws from are selectively due to the Eugene and Agnes E. Meyer Foundation, the Edgar Stern Family Fund, The National Institute for Mental Health, the Baltimore-Washington Institute for Psychoanalysis and the Department of Psychiatry, Children's Hospital National Medical Center.  相似文献   
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A number of researchers have recently challenged the long-held notion among criminologists that rape, along with most other violent crimes, is an intraracial crime. Based on analysis of survey data they concluded that black rapists “prefer” or “seek out” white victims and that the likelihood of a black offender selecting a white victim has been increasing during recent years. Data presented here (1977–88 National Crime Surveys) refute the notion that black rapists “prefer” white victims. Moreover these same data fail to support the contention that rapes involving black offenders and white victims have been increasing. According to National Crime Survey estimates, the proportion of black offenders that victimize whites has been declining. An earlier version of this paper was presented at the annual meetings of the American Society of Criminology, November 1991.  相似文献   
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