In this paper, inference for the scale parameter of lifetime distribution of a k-unit parallel system is provided. Lifetime distribution of each unit of the system is assumed to be a member of a scale family of distributions. Maximum likelihood estimator (MLE) and confidence intervals for the scale parameter based on progressively Type-II censored sample are obtained. A β-expectation tolerance interval for the lifetime of the system is obtained. As a member of the scale family, half-logistic distribution is considered and the performance of the MLE, confidence intervals and tolerance intervals are studied using simulation. 相似文献
This paper addresses the poverty of services available to lesbian victims of partner abuse, despite the need for such services. Drawing on data from a survey of 1,505 help providers (to which 566 responded), the paper focuses on the services that the help providers themselves claim to offer. The data reveal a serious disparity in help providers' rhetoric and offical policies and the reality of the services available. The paper concludes with suggestions for improving services to battered lesbians. 相似文献
Some degree of error is inevitable in multi‐agent bioassays regardless of design or measurement technology. Estimation error can be reduced post facto by exploiting the matrix partial ordering of the bioassay survival estimates. The standard method for this is order‐restricted regression (ORR). If the joint action of the bioassay agents admits a tolerance‐based interpretation, additional structure beyond matrix partial ordering is available, leading to a new method of error reduction. This tolerance‐based error reduction (TBER) procedure almost always outperforms ORR. Like ORR, TBER applies to complete factorial bioassay designs and, using weighting, to incomplete designs. 相似文献
Has civil society declined in the United States in the past 20 years? Multiple indicators suggest evidence for decline. This paper questions Robert Putnam's generational explanation for decline and suggests an alternative explanation, namely the structural economic transformation of the U.S. and how it has been managed. Individuals' perceptions of economic distress have increased since 1972 and are related to changes in indicators of civil society, including associational memberships, trust, anomia, and espoused racial and gay tolerance. Economic distress is also related to political interest and participation. Other consequences of an eroding civil society are discussed, including rising crime and inhibited economic productivity