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951.
A measure of multicollinearity is defined which is useful in evaluating maintained hypotheses and aiding estimator selection as it suggests when a non-traditional estimator proposed by Bock (1975) is minimax and dominates ordinary least squares. An example is used to illustrate the presented methodology.  相似文献   
952.
This paper considers the effects of the presence of eqmi-correlation between observations in a k-way factorial experiment, A technique to provide unbiased F-tests is also constructed.  相似文献   
953.
This study reports preliminary findings regarding the feasibility and efficacy of a novel couple-based treatment, named Strategic Approach Therapy (SAT), for reducing avoidance symptoms of posttraumatic stress disorder (PTSD). Six male Vietnam combat veterans diagnosed with PTSD and their cohabitating marital partners participated in 10 weeks of SAT treatment. Self-report, clinician ratings, and partner ratings of PTSD symptoms were obtained before the first session and after the tenth session of treatment. Veterans reported statistically significant reductions in self-reported, clinician-rated, and partner-rated effortful avoidance, emotional numbing, and overall PTSD severity. These data indicate that SAT offers promise as an effective treatment for PTSD avoidance symptoms.  相似文献   
954.
This prospective longitudinal study examined the unique and combined effects of neighborhood characteristics on parental behaviors in the context of more distal and more proximal influences. With a sample of 368 mothers from high‐risk communities in 4 parts of the United States, this study examined relations between race (African American or European American), locality (urban or rural), neighborhood characteristics, family context, and child problem behaviors, and parental warmth, appropriate and consistent discipline, and harsh interactions. Analyses testing increasingly proximal influences on parenting revealed that initial race differences in warmth and consistent discipline disappeared when neighborhood influences were considered. Although generally culture and context did not moderate other relations found between neighborhood characteristics, family context, and child behaviors, the few interactions found highlight the complex influences on parenting.  相似文献   
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In five Lincolnshire villages between 1252 and 1478 there is evidence that men and women married fairly late before the Black Death, and that by 1348/9 the Western European marriage pattern of late and prudential marriage was well established. Households were usually nucleated; husbands were on average eight years older than their wives before 1348/9, and five years older after 1348/9. Marriages were short: according to the best calculation shorter before 1348/9 than after, most often terminated by the death of the first husband, and were unlikely to produce more than three children. Since there were more males than females amongst children and young adults, many men remained unmarried, but since the death rate of women was very high, men lived longer.  相似文献   
960.
Comments     

In this paper we compare Bartlett-corrected, bootstrap, and fast double bootstrap tests on maximum likelihood estimates of cointegration parameters. The key result is that both the bootstrap and the Bartlett-corrected tests must be based on the unrestricted estimates of the cointegrating vectors: procedures based on the restricted estimates have almost no power. The small sample size bias of the asymptotic test appears so severe as to advise strongly against its use with the sample sizes commonly available; the fast double bootstrap test minimizes size bias, while the Bartlett-corrected test is somehow more powerful.  相似文献   
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