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91.
Summary Based on 14 case studies of highly effective therapies and the reasons they succeeded less frequently than they could, we
propose a variety of steps to improve the health care system of the U.S.A. Whatever proposal emerges from current national
debates until innovations are shown to be safe and effective, they should not be supported; when slightly better technologies
are much more expensive than other good ones we need to consider appropriate choices carefully; simplified billing and bookkeping
would reduce our costs; when a technology is rapidly introduced cautionnary measures may be needed; tracking immunization
and repairing their omissions requires a new system; educational programs such as seen effective in hypertension should be
applied in other areas such as vaccination; in organ transplantation the nation should consider “presumed consent”; our payment
system sometimes creates perverse incentives and therefore needs review; and the preferences of the public in allocation of
health resources need to be discovered once the public is informed about the issues.
Research supported by Andrew W. Mellon Foundation. 相似文献
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In the development of many diseases there are often associated random variables which continuously reflect the progress of a subject towards the final expression of the disease (failure). At any given time these processes, which we call stochastic covariates, may provide information about the current hazard and the remaining time to failure. Likewise, in situations when the specific times of key prior events are not known, such as the time of onset of an occult tumour or the time of infection with HIV-1, it may be possible to identify a stochastic covariate which reveals, indirectly, when the event of interest occurred. The analysis of carcinogenicity trials which involve occult tumours is usually based on the time of death or sacrifice and an indicator of tumour presence for each animal in the experiment. However, the size of an occult tumour observed at the endpoint represents data concerning tumour development which may convey additional information concerning both the tumour incidence rate and the rate of death to which tumour-bearing animals are subject. We develop a stochastic model for tumour growth and suggest different ways in which the effect of this growth on the hazard of failure might be modelled. Using a combined model for tumour growth and additive competing risks of death, we show that if this tumour size information is used, assumptions concerning tumour lethality, the context of observation or multiple sacrifice times are no longer necessary in order to estimate the tumour incidence rate. Parametric estimation based on the method of maximum likelihood is outlined and is applied to simulated data from the combined model. The results of this limited study confirm that use of the stochastic covariate tumour size results in more precise estimation of the incidence rate for occult tumours. 相似文献
96.
This study investigated the gender-specific, self-reported sexual behaviors and attitudes of never-married college students attending a southeastern university in 1973 and 1988. Data were collected by means of a mailed questionnaire that remained essentially unchanged for both years. The authors found that both men and women reported an increase in heterosexual relationships that included sexual intercourse and a decrease in nonsexual relationships with the other gender. The majority of the students perceived themselves as adequately informed about sexuality and satisfied with their relationships, although the proportion of men who reported being satisfied with their relationships declined over the 15 years. The students indicated that sexuality education should focus primarily on information about AIDS and on preparation for marriage. 相似文献
97.
THE INFLUENCE OF ECONOMICS ON ANTITRUST LAW 总被引:1,自引:0,他引:1
WILLIAM E. KOVACIC 《Economic inquiry》1992,30(2):294-306
Economists today play prominent roles in formulating antitrust policy and litigating antitrust cases. This paper explains why economics influences antitrust law and describes how economic theories enter and shape the antitrust system. Antitrust policy and doctrine change over time in response to developments in economic theory, and the decentralization of the antitrust adjudication system and the wide latitude accorded judges in interpreting antitrust statutes ensure that legal rules will reflect advances in the economic literature concerning the appropriate content of standards governing business conduct. 相似文献
98.
Bivariate probit estimates with partial observability identify the factors influencing the worker’s decision to seek a state
or local government job and the factors influencing the government’s decision to hire particular workers. The estimates routinely
confirm the presence of a local job queue but confirm the presence of a state job queue only when the role of unionization
is explicitly recognized. Our results suggest that the net benefits from local and state government employment are greater
than those from private sector employment. The estimates also indicate that local governments disproportionately hire racial
minorities relative to the local governments’ pool of applicants but indicate no such relationship for state governments.
The authors thank Dale Belman, Jugal Ghorai, and Matt Higgins for help on this and related work. We also thank the referee
and the editor for useful suggestions. 相似文献
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Rapid advances in sociological computing are changing virtually every aspect of scholarly sociological work. These changes
offer an opportunity for sociologists to improve the quality of their work and bring new insights and approaches to bear on
important sociological problems. Nevertheless, sociologists display a profound ambivalence toward computer work by other sociologists.
Left unchecked, this ambivalence threatens to turn sociological computing into an opportunity missed. Inadequate rewards,
lack of training, and a general failure to understand the importance of computing in sociology threaten to stifle the development
of quality soft-ware, push sociologists competent in computing into other fields, and jeopardize the quality of sociological
scholarship. This article documents these ambivalent tendencies and proposes reasonable steps the discipline should take to
assure that sociological computing does not become an opportunity missed. 相似文献