Correcting sample selection in FARS data to estimate seatbelt use

Introduction

In this paper, we show that FARS data can be a comparable alternative to observational NOPUS data in estimating seat belt use in the United States once we correct for sample selection bias.

Results

Based on assumptions of independence for seatbelt choice, we establish a lower and upper bound for seatbelt usage rates, and find that once we correct for sample selection bias, the seatbelt usage estimates from the corrected FARS emerge at least as a comparable alternative to NOPUS estimates.

Impact on Industry

This implies that researchers can use corrected FARS to complement NOPUS, thus being able to utilize the rich cross-sectional details available in FARS data to analyze various relevant research questions.     

Comparative study of photovoltaic technologies based on performance,cost and space requirement: Strategy for selection and application

The module performance is an important consideration for selecting PV technologies for electricity production, as well as the economic aspect. Also, PV energy yield under varying environmental conditions is largely dependent on the type of technology used. Therefore, this article presents a comparative analysis of different PV modules, of the same power, namely, monocrystalline, polycrystalline, amorphous silicon and hybrid, based on performance, cost and space requirement. The performance is evaluated in terms of module power output, yield, capture losses, fill factor and efficiency, according to the IEC 61724 standards, using Gwako, Nigeria as a case study. A novel technique called Fundamental PV Module Performance Analysis is used to analyze and compare the performance of the PV modules. The performance of a single module is then employed to calculate the overall performance of a PV array designed for a small off-grid house, and a suitable module is determined amongst the modules under study. Results provide insights into the behaviors of the different technologies with the environmental factors of the location, which have an impact on their power and kWh/kW outputs and the efficiency. This knowledge, coupled with the understanding of the constraints of cost and the module space requirements would be useful to researchers, engineers, installers etc. in Nigeria, for planning and developing photovoltaic electric systems for off-grid applications.     

Regional Management of Farmland Feeding Geese Using an Ecological Prioritization Tool

Wild geese foraging on farmland cause increasing conflicts with agricultural interests, calling for a strategic approach to mitigation. In central Norway, conflicts between farmers and spring-staging pink-footed geese feeding on pastures have escalated. To alleviate the conflict, a scheme by which farmers are subsidized to allow geese to forage undisturbed was introduced. To guide allocation of subsidies, an ecological-based ranking of fields at a regional level was recommended and applied. Here we evaluate the scheme. On average, 40 % of subsidized fields were in the top 5 % of the ranking, and 80 % were within the top 20 %. Goose grazing pressure on subsidized pastures was 13 times higher compared to a stratified random selection of non-subsidized pastures, capturing 67 % of the pasture feeding geese despite that subsidized fields only comprised 13 % of the grassland area. Close dialogue between scientists and managers is regarded as a key to the success of the scheme.     

Eco-material selection using fuzzy TOPSIS method

In the classical multiple attribute decision-making or MADM methods, the ratings and the weights of the criteria are known precisely. However, in eco-material selection exercises, the available data are typically inadequate because of the selection dual quantitative and qualitative natures. Some of the qualitative selection criteria can be rated in several classes rather being expressed by exact numerical values; hence the application of fuzzy concepts in decision-making seems attractive to deal with such kind of ratings. Thusly, the presented study attempts to propose an eco-material selection approach specific to the automobile body panels using a fuzzy technique for order preference by similarity to ideal solution (TOPSIS), to incorporate both numerical and rating-based criteria into one holistic sustainability model. TOPSIS and fuzzy logic can aid the material selection process in translating the design goals and parameters into usable numbers that in turn can be used to rank candidate materials in their closeness to the ideal solution. An additional uniqueness of this study stems from using the fuzzy-TOPSIS as a scoring tool without any assigned weights for the different selection attributes, in order to avoid the bias that is typically associated with other classical MADM, such as quality function deployment, analytical hierarchy process and digital logic.     

城市污水处理厂工艺方案选择技术经济分析

城市污水处理厂需要较大的投资和运营费用.在我国目前经济条件比较落后,怎样用最少的钱达到最佳的处理效果非常关键.污水处理厂建设中最重要的就是污水处理工艺的选择.通过工程预算得到不同工艺不同规模的处理方案的总费用,通过曲线拟和得到不同工艺的费用和规模的函数关系式.根据技术经济学原理,将污水治理项目的费用和削减污染物的数量相联系,对项目的费用流和削减污染物负荷流进行贴现计算.     

遗传算法对QSAR研究中变量选择的应用

将遗传算法引入定量结构活性关系（ＱＳＡＲ）研究中,对变量进行造反选择,可同时建立几种比较好的ＱＳＡＲ模型,并以交互验证的决定系数作为适应函数,以保证模型质量的可靠性。将其分别应用于氯代酚和单取代苯系列化合物,均得到较好的结果。同时,在这些应用中也反映了遗传算法在变量选择中存在的局限性,限不能保证选择的所有变量在模型中都有显著贡献。     

Male-male competition ensures honest signaling of male parental ability in the three-spined stickleback (Gasterosteus aculeatus)

The importance of socially imposed costs for the evolution and maintenance of honest sexual signals has received less attention than other costs. Here I show that male-male competition can increase the honesty of sexual signaling in relation to male parental ability in a species with flexible signaling. When four three-spined stickleback (Gasterosteus aculeatus) males were allowed to court a female first separately and then in competition, red nuptial coloration under competition reflected male parental ability more accurately than red coloration when separated. Parental ability was determined as the ability of the male to raise a clutch of eggs to the hatching stage under interaction with other breeding and non-breeding males. The increased honesty under competition was probably due to subordinate males of poor parental ability decreasing their color expression under interaction to reduce the risk of fights with superior males. However, socially imposed costs of signaling were probably not the main factors maintaining honest signaling, as red coloration reflected male parental ability also in the absence of competition, although less accurately. Nevertheless, the small-scale differences that male-male competition induced can significantly facilitate adaptive female choice and have large impacts on sexual selection. Received: 7 July 2000 / Revised: 31 August 2000 / Accepted: 4 September 2000     

Post-mating odor in females of the solitary bee, Andrena nigroaenea (Apoidea, Andrenidae), inhibits male mating behavior

We investigated odor changes and their behavioral significance in the solitary, ground-nesting bee Andrena nigroaenea. We used gas chromatography with electroantennographic detection and performed behavioral tests with males in the field using natural odor samples and synthetic compounds. We found that only cuticle extracts of young females elicited copulation attempts in the males. We demonstrated that among the 17 compounds which triggered electroantennographic responses, all-trans-farnesyl hexanoate and all-trans-farnesol were significantly more abundant in unattractive cuticle extracts of A. nigroaenea females. Dufour’s gland extracts of these females also contained greater amounts of both compounds. In bioassays using synthetic farnesyl hexanoate and farnesol we found that these compounds inhibit copulation behavior in the males. Farnesyl hexanoate is probably synthesized in Dufour’s gland and used by females for lining brood cells. We interpret the semiochemical function of farnesyl hexanoate and its precursor farnesol to have evolved secondarily. As an outcome of sexual selection, it facilitates the discrimination by males of receptive females from nesting and thus already mated individuals. The dual function of these compounds represents an elegant parsimony in the chemical communication system of this insect. Received: 19 January 2000 / Revised: 29 May 2000 / Accepted: 24 June 2000     

Limitations to colour-based sexual preferences in three-spined sticklebacks (Gasterosteus aculeatus)

Female three-spined sticklebacks (Gasterosteus aculeatus) are suggested to select mates based on their red nuptial coloration, males with a redder display being more preferred. Although there are both laboratory and field data to support this view, there are also published accounts where females do not show a preference for the redder male. Here we report the results of a series of 19 trials where receptive gravid female three-spined sticklebacks were allowed to choose between two size-matched rival males. We used photographic and image analysis techniques to quantify male nuptial coloration to investigate how the magnitude of the colour difference between the two alternative males influenced female preferences. Using the amount of time a female spent oriented towards each male as a measure of his attractiveness to her, females were not always found to select the redder of the two presented males. We did, however, find that that the relative difference in coloration of the two males in each pair was important in determining the level of coloration-based preference, with females only selecting redder males consistently when the difference in coloration was sufficiently large. Received: 26 October 1999 / Received in revised form: 10 January 2000 / Accepted: 13 February 2000     

Male greenfinches (Carduelis chloris) with brighter ornaments have higher virus infection clearance rate

Hamilton and Zuk proposed that bright plumage in birds indicates genetic resistance to parasites, and that by selecting brighter males as mates, females can increase their offspring’s fitness due to this inherited resistance. The theory predicts a negative relationship between parasite load and plumage brightness in males. We used Sindbis virus clearance rate after an experimental infection to quantify parasite resistance in male greenfinches (Carduelis chloris) and related variation in clearance rate with variation in male plumage brightness. We found that certain aspects of brightness of the male plumage (i.e. tail-patch area) could be used to predict the virus infection clearance rate. Wing brightness was uninformative of virus clearance rate, but revealed age class. We found no clear relationship between antibody production rate and virus clearance rate or total viraemia. However, males with large tail patches tended to have a higher antibody production rate. The results suggest that the size of the male tail patch may function as an indicator of an individual male’s ability to resist parasite infections, thus supporting the Hamilton-Zuk theory for a novel taxon of parasites, a virus. Received: 11 November 1999 / Received in revised form: 13 March 2000 / Accepted: 1 April 2000