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Randomized response techniques are widely employed in surveys dealing with sensitive questions to ensure interviewee anonymity and reduce nonrespondents rates and biased responses. Since Warner’s (J Am Stat Assoc 60:63–69, 1965) pioneering work, many ingenious devices have been suggested to increase respondent’s privacy protection and to better estimate the proportion of people, π A , bearing a sensitive attribute. In spite of the massive use of auxiliary information in the estimation of non-sensitive parameters, very few attempts have been made to improve randomization strategy performance when auxiliary variables are available. Moving from Zaizai’s (Model Assist Stat Appl 1:125–130, 2006) recent work, in this paper we provide a class of estimators for π A , for a generic randomization scheme, when the mean of a supplementary non-sensitive variable is known. The minimum attainable variance bound of the class is obtained and the best estimator is also identified. We prove that the best estimator acts as a regression-type estimator which is at least as efficient as the corresponding estimator evaluated without allowing for the auxiliary variable. The general results are then applied to Warner and Simmons’ model.  相似文献   
33.
In this case study, we detail and analyze how the Tobacco Control Evaluation Center (TCEC), an evaluation technical assistance center that serves approximately 100 local tobacco control organizations in California, endeavors to build capacity among the state-funded local providers it serves by using evaluation capacity building activities with an utilization-focused evaluation framework. We call this a "blended approach" and describe these methods. Satisfaction and demand for TCEC services are documented to provide measurements for evaluation capacity building. Final evaluation report scores from two intervention cycles (2004-2007 and 2007-2010) submitted to the California Health Department, Tobacco Control Division are also assessed and compared. These measures demonstrate an increase in evaluation capacity by local projects under TCEC's purview.  相似文献   
34.
In this paper we introduce a new family of robust estimators for ARMA models. These estimators are defined by replacing the residual sample autocovariances in the least squares equations by autocovariances based on ranks. The asymptotic normality of the proposed estimators is provided. The efficiency and robustness properties of these estimators are studied. An adequate choice of the score functions gives estimators which have high efficiency under normality and robustness in the presence of outliers. The score functions can also be chosen so that the resulting estimators are asymptotically as efficient as the maximum likelihood estimators for a given distribution.  相似文献   
35.
Since the early 1990s, the dominant consensus in the debate on land rights reform in sub‐Saharan Africa has been that external interventions to privatise land rights are usually inappropriate and likely to remain so. This article suggests that two elements in the debate – the scope for varying adjudication criteria, procedures and support systems in order to enhance equity, and the influence of a region's agro‐ecological and socioeconomic characteristics on the impacts of tenure change – merit further attention. The article urges a shift towards a more pragmatic approach, sensitive to the diversity of both physical and socio‐economic conditions within which tenure systems operate. Illustrative evidence is drawn from a relatively low‐potential farming region in eastern Kenya.  相似文献   
36.
The U.S. Department of Energy has estimated that over 50 GW of offshore wind power will be required for the United States to generate 20% of its electricity from wind. Developers are actively planning offshore wind farms along the U.S. Atlantic and Gulf coasts and several leases have been signed for offshore sites. These planned projects are in areas that are sometimes struck by hurricanes. We present a method to estimate the catastrophe risk to offshore wind power using simulated hurricanes. Using this method, we estimate the fraction of offshore wind power simultaneously offline and the cumulative damage in a region. In Texas, the most vulnerable region we studied, 10% of offshore wind power could be offline simultaneously because of hurricane damage with a 100‐year return period and 6% could be destroyed in any 10‐year period. We also estimate the risks to single wind farms in four representative locations; we find the risks are significant but lower than those estimated in previously published results. Much of the hurricane risk to offshore wind turbines can be mitigated by designing turbines for higher maximum wind speeds, ensuring that turbine nacelles can turn quickly to track the wind direction even when grid power is lost, and building in areas with lower risk.  相似文献   
37.
Factor screening designs for searching two and three effective factors using the search linear model are discussed. The construction of such factor screening designs involved finding a fraction with small number of treatments of a 2m factorial experiment having the property P2t (no 2t columns are linearly dependent) for t=2 and 3. A ‘Packing Problem’ is introduced in this connection. A complete solution of the problem in one case and partial solutions for the other cases are presented. Many practically useful new designs are listed.  相似文献   
38.
This study examines the influence on CEO paypractices of four corporate control perspectives:managerial control, class hegemony, external control,and efficient market. The results indicate the influence of both market and extra-market controls on thedetermination of CEO pay levels and criteria.Implications for the governance of firms and the studyof corporate control are drawn.  相似文献   
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It has been argued that transracially adopted children have increased risk of problems related to self-esteem and ethnic identity development. We evaluated this hypothesis across four groups of transracial adoptees: Asian (n = 427), Latino (n = 28), Black (n = 6), mixed/other (n = 20), and same-race White adoptees (n = 126) from 357 adoptive families. No mean differences were found in adoptees’ ratings of affect about adoption or of curiosity about birth parents. Some differences were found in general identity development and adjustment. There were notable differences in communication about race/ethnicity across groups and between parent and child report.  相似文献   
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