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221.
Andreea L. Erciulescu Nathan B. Cruze Balgobin Nandram 《Environmental and Ecological Statistics》2018,25(4):523-547
The publication of official statistics at different levels of aggregation requires a benchmarking step. Difficulties arise when a benchmarking method needs to be applied to a triplet of related estimates, at multiple stages of aggregation. For ratios of totals, external benchmarking constraints for the triplet (numerator, denominator, ratio) are that the weighted sum of denominator/numerator/ratio estimates equals to a constant. The benchmarking weight, applied to the ratio estimates, is a function of the denominator estimates. For example, the United States Department of Agriculture’s National Agricultural Statistics Service’s county-level, end-of-season acreage, production and yield estimates need to aggregate to the corresponding agricultural statistics district-level estimates, which also need to aggregate to the corresponding prepublished state-level values. Moreover, the definition of yield, as the ratio of production to harvested acreage, needs to hold at the county level, the agricultural statistics district level and the state level. We discuss different methods of applying benchmarking constraints to a triplet (numerator, denominator, ratio), at multiple stages of aggregation, where the denominator and the ratio are modeled and the numerator is derived. County-level and agricultural statistics district-level, end-of-season acreage, production and yield estimates are constructed and compared using the different methods. Results are illustrated for 2014 corn and soybean in Indiana, Iowa and Illinois. 相似文献
222.
We examined whether sexualizing a businesswoman impacts attitudes toward subsequently evaluated, nonsexualized females applying for a corporate managerial position. Research shows that sexualized women are perceived as less warm and competent (i.e., objectified). Integrating this work with research on social cognition, we hypothesized that the negative effect of sexualization “spills over” onto other nonsexualized women, reducing their hireability. Across two experiments, initially sexualized women were perceived as less warm and competent, as were subsequently evaluated nonsexualized female job candidates. In turn, these negative perceptions reduced the applicants' probability of being hired. Sexualization of women also increased intentions to hire a subsequently evaluated male candidate. The results were robust when we controlled for evaluators' gender and age. Our findings demonstrate that female job applicants can experience detrimental effects from sexually based objectification, even when they are not the individuals initially sexualized. We discuss implications for women's careers. 相似文献
223.
Nicholas S. Gladstone Matthew L. Niemiller Benjamin Hutchins Benjamin Schwartz Alexander Czaja Michael E. Slay Nathan V. Whelan 《Conservation biology》2022,36(1):e13722
Many taxonomic groups successfully exploit groundwater environments and have adapted to a subterranean (stygobiotic) existence. Among these groups are freshwater gastropods (stygosnails), which represent a widespread and taxonomically diverse component of groundwater ecosystems in North America. However, owing to sampling difficulty and lack of targeted study, stygosnails remain among the most understudied of all subterranean groups. We conducted a literature review to assess the biodiversity and geographic associations of stygosnails, along with the threats, management activities, and policy considerations related to the groundwater systems they inhabit. We identified 39 stygosnail species known to occur in a range of groundwater habitats from karst regions in the United States and Mexico. Most stygosnails exhibit extreme narrow-range endemism, resulting in a high risk of extinction from a single catastrophic event. We found that anthropogenically driven changes to surface environments have led to changes in local hydrology and degradation of groundwater systems inhabited by stygosnails such as increased sedimentation, introduction of invasive species, groundwater extraction, or physical collapse of water-bearing passages. Consequently, 32 of the 39 described stygosnail species in the United States and Mexico have been assessed as imperiled under NatureServe criteria, and 10 species have been assessed as threatened under International Union for Conservation of Nature criteria. Compared with surface species of freshwater snails, stygosnail conservation is uniquely hindered by difficulties associated with accessing subterranean habitats for monitoring and management. Furthermore, only three species were found to have federal protection in either the United States or Mexico, and current laws regulating wildlife and water pollution at the state and federal level may be inadequate for protecting stygosnail habitats. As groundwater systems continue to be manipulated and relied on by humans, groundwater-restricted fauna such as stygosnails should be studied so unique biodiversity can be protected. 相似文献