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Darrell O. Ricke Ph.D. Philip Fremont‐Smith M.S. James Watkins B.S. Sara Stankiewicz M.S. Tara Boettcher B.S. Eric Schwoebel Ph.D. 《Journal of forensic sciences》2019,64(5):1468-1474
High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures. 相似文献
65.
In recent years controversy has arisen over whether the rate of women's gun ownership has increased over time. While media reports claimed a rising trend in women's gun ownership, existing scholarly studies found stable rates over time. This paper investigates the issue using the 1973–2002 General Social Survey data. Our bivariate analysis reveals a declining trend in female gun ownership, especially in recent years. The logistic regression results indicate that holding relevant variables constant, the probability of female gun ownership decreases over time. Comparisons are also made with men. Similar results for male gun ownership are obtained. Possible explanations and implications of findings are discussed. 相似文献
66.
Research into e-government is relatively new. Nevertheless, much contemporary thinking and writing about e-government is driven by normative models that appeared less than a decade ago. The authors present empirical evidence from three surveys of local e-government in the United States to test whether these models are accurate or useful for understanding the actual development of e-government. They find that local e-government is mainly informational, with a few transactions but virtually no indication of the high-level functions predicted in the models. Thus, the models do not accurately describe or predict the development of e-government, at least among American local governments. These models, though intellectually interesting, are purely speculative, having been developed without linkage to the literature about information technology and government. The authors offer grounded observations about e-government that will useful to scholars and practitioners alike. 相似文献
67.
Results from previous studies of campaign spending imply that equal-sized grants to both incumbents and challengers are a net benefit to challengers, who on average spend less money and derive greater marginal returns from each additional dollar. This study provides an experimental test of this proposition. Cities holding mayoral elections in November 2005 and 2006 were randomly assigned to broadcast nonpartisan radio ads that stated the names of the mayoral candidates, reminded listeners about the date of the upcoming election, and encouraged them to vote. Consistent with the findings of previous studies on the differential effects of incumbent and challenger campaign spending on election outcomes, we find that these radio ads produced substantially more competitive elections. The borderline statistical significance of our results, however, invites replication of this experiment. 相似文献
68.
While there is a growing academic literature about mail-in ballots, there has been no serious academic research to date on overseas voters, even though the counting of overseas military ballots figured into the 2000 presidential election controversy. The participation of nearly 4 million overseas voters, both civilian and military, is governed by the Uniformed and Overseas Citizens Absentee Voting Act. The authors examine the reported perceptions of military and nonmilitary voters covered by this legislation using two surveys funded by the U.S. Election Assistance Commission, focusing on their perceptions of electronic means of transmitting voting materials. The authors find that civilian overseas citizens have a harder time registering and voting than military overseas citizens; that the key factor is the timely transmission of voting materials; and that, despite privacy concerns, electronic transmission of voting materials is viewed favorably. 相似文献
69.
Local election officials are the administrators of democracy, but we know little about their views. This paper draws from two national surveys of local election officials. The authors find that local election officials generally support the goals of the federal Help America Vote Act but are less enthusiastic about the actual impact of the legislation. Implementation theory helps explain their evaluation of federal reforms. Goal congruence with reform mandates, resource availability, and a willingness to accept federal involvement predicts support for these reforms. Federal policy changes have promoted electronic systems, and some of the authors' findings are relevant to research on e-government. Users of electronic voting machines tend to have high confidence in them despite the significant criticism the machines have faced. Local election officials who support e-government generally are more likely to more positively evaluate federal reforms. 相似文献
70.
Explanations of party competition and vote choice are commonly based on the Downsian view of politics: parties maximise votes by adopting positions on policy dimensions. However, recent research suggests that British voters choose parties based on evaluations of competence rather than on ideological position. This paper proposes a theoretical account which combines elements of the spatial model with the ‘issue ownership’ approach. Whereas the issue ownership theory has focused mainly on party competition, this paper examines the validity of the model from the perspective of both parties and voters, by testing its application to recent British general elections. Our findings suggest that as parties have converged ideologically, competence considerations have become more important than ideological position in British elections. 相似文献