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Using Ecological Inference Point Estimates as Dependent Variables in Second-Stage Linear Regressions 总被引:1,自引:0,他引:1
The practice of using point estimates produced by the King ecologicalinference technique as dependent variables in second-stage linearregressions leads to second-stage results that, in general,are inconsistent. This conclusion holds even when all assumptionsbehind King's ecological technique are satisfied. Second-stageinconsistency is a consequence of the fact that King-based pointestimates of disaggregated quantities contain errors correlatedwith the true quantities the estimates measure. Our findingson second-stage inconsistency, as well as a fix that we propose,follow from econometric theory in conjunction with an analysisof simulated and real ecological data sets. 相似文献
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We report here the results of mtDNA analysis of remains exhumed in July, 1995 from Mt. Olivet Cemetery in Kearney, Nebraska, that are thought to be those of Jesse James. The remains were poorly preserved, presumably due to wet and slightly acidic soil conditions, and insufficient DNA for analysis was obtained from two bone samples. However, two of four teeth, and two hairs recovered in 1978 from the original burial site on the James Farm, did yield reproducible mtDNA sequences. These mtDNA sequences from the teeth and hairs were all identical, suggesting that they came from the same individual; furthermore, this mtDNA sequence was identical to mtDNA sequences determined from blood samples from two maternal relatives of Jesse James. Therefore, either the remains are indeed those of Jesse James, or they are from an unrelated individual who, by chance, happens to have the same mtDNA sequence. To assess the probability that an unrelated individual would have the same sequence, we searched the forensic mtDNA database, and found that this sequence does not appear among the 2426 mtDNA sequences therein. Hence, the mtDNA analysis supports the identification of the exhumed remains from Mt. Olivet Cemetery as those of Jesse James. 相似文献
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