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91.
In this paper, we propose the incremental group testing model for the gap closing problem, which assumes that we can tell the difference between the outcome of testing a subset S, and the outcome of testing S {x}. We also give improvements over currently best results in literature for some other models.  相似文献   
92.
Waters  Robert D.  Parker  Frank L. 《Risk analysis》1999,19(2):249-259
The reliability of a treatment process is addressed in terms of achieving a regulatory effluent concentration standard and the design safety factors associated with the treatment process. This methodology was then applied to two aqueous hazardous waste treatment processes: packed tower aeration and activated sludge (aerobic) biological treatment. The designs achieving 95 percent reliability were compared with those designs based on conventional practice to determine their patterns of conservatism. Scoping-level treatment costs were also related to reliability levels for these treatment processes. The results indicate that the reliability levels for the physical/chemical treatment process (packed tower aeration) based on the deterministic safety factors range from 80 percent to over 99 percent, whereas those for the biological treatment process range from near 0 percent to over 99 percent, depending on the compound evaluated. Increases in reliability per unit increase in treatment costs are most pronounced at lower reliability levels (less than about 80 percent) than at the higher reliability levels (greater than 90 percent, indicating a point of diminishing returns. Additional research focused on process parameters that presently contain large uncertainties may reduce those uncertainties, with attending increases in the reliability levels of the treatment processes.  相似文献   
93.
The Duckworth–Lewis method for adjusting targets in rain-interrupted one-day cricket matches is used throughout the world, but, as Frank Duckworth explains, he originally came to statistics from physics via metallurgy, and only thought of applying statistical methods to sport when their power became apparent to him during his career in the nuclear energy industry  相似文献   
94.
The use of lower probabilities is considered for inferences in basic jury scenarios to study aspects of the size of juries and their composition if society consists of subpopulations. The use of lower probability seems natural in law, as it leads to robust inference in the sense of providing a defendant with the benefit of the doubt. The method presented in this paper focusses on how representative a jury is for the whole population, using a novel concept of a second ’imaginary’ jury together with exchangeability assumptions. It has the advantage that there is an explicit absence of any assumption with regard to guilt of a defendant. Although the concept of a jury in law is central in the presentation, the novel approach and the conclusions of this paper hold for representative decision making processes in many fields, and it also provides a new perspective to stratified sampling.  相似文献   
95.
The aim of this study was to examine the relations between popularity and different types of aggressive, destructive, and norm‐breaking behaviors in a large cross‐sectional sample of adolescents (N=3,312, M age=13.60). We were interested in the extent to which the relations of these behaviors with popularity were moderated by positive features (i.e., athletic abilities, physical attractiveness, and prosociality). From a goal‐framing perspective, it was argued that positive features evoke positive affect, which in turn enhances the positive impact of aggressive, destructive, and norm‐breaking behaviors on popularity. The results supported our notion that these latter behaviors are especially related to popularity in adolescents who also exhibit positive features.  相似文献   
96.
97.
Nonindigenous species have caused significant impacts to North American forests despite past and present international phytosanitary efforts. Though broadly acknowledged, the risks of pest invasions are difficult to quantify as they involve interactions between many factors that operate across a range of spatial and temporal scales: the transmission of invading organisms via various pathways, their spread and establishment in new environments. Our study presents a stochastic simulation approach to quantify these risks and associated uncertainties through time in a unified fashion. We outline this approach with an example of a forest pest recently detected in North America, Sirex noctilio Fabricius. We simulate new potential entries of S. noctilio as a stochastic process, based on recent volumes of marine shipments of commodities from countries where S. noctilio is established, as well as the broad dynamics of foreign marine imports. The results are then linked with a spatial model that simulates the spread of S. noctilio within the geographical distribution of its hosts (pines) while incorporating existing knowledge about its behavior in North American landscapes. Through replications, this approach yields a spatial representation of S. noctilio risks and uncertainties in a single integrated product. The approach should also be appealing to decisionmakers, since it accounts for projected flows of commodities that may serve as conduits for pest entry. Our 30-year forecasts indicate high establishment probability in Ontario, Quebec, and the northeastern United States, but further southward expansion of S. noctilio is uncertain, ultimately depending on the impact of recent international treatment standards for wood packing materials.  相似文献   
98.
While utilizing social networks is common in labor markets and may benefit both firms and laborers, social networks are argued to be unusually important in the popular arts. Prior work in economics on the role of relationships in labor markets has generally focused on the benefits and not the costs. This paper takes a different approach by focusing on both costs and benefits, by examining a specific market where relationships are particularly important. This paper argues that in addition to reducing diversity and creating inherent inequalities, excessive reliance on networks can lead to higher agency costs and lower product quality.  相似文献   
99.
Family communication about adolescent sexual health and behavior promotes adolescent health and family connectedness. However, few studies seek the perspective of adolescents regarding their recommended strategies for family communication. Findings of a survey of female adolescent family planning patients (n = 249) indicated adolescent recommendations for better family communication included treat teen as an equal, 63%; increase parental knowledge about lifestyle and peer pressures, 61%, and improve parental listening skills, 61%. There were no statistically significant differences according to age, pregnancy history, or school enrollment status for suggested strategies for improved communication with parents. Sexually active adolescent daughters expressed interest in maintaining family connectedness and support with increased time for family activities as well as increased quality and quantity of dialogue between the adolescent girl and her parents.  相似文献   
100.
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