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11.
The matching identification problem (MIP) is a combinatoric search problem related to the fields of learning from examples, boolean functions, and knowledge acquisition. The MIP involves identifying a single “goal” item from a large set of items. Because there is commonly a cost associated with evaluating each guess, the goal item should be identified in as few guesses as possible. As in most search problems, the items have a similar structure, which allows an evaluation of each guessed item. In other words, each guessed item elicits partial information about the goal item, i.e. how similar the guess is to the goal. With this information the goal is more quickly identified.The unordered MIP has been studied by Mehrez and Steinberg (ORSA J. Comput. 7 (1995) 211) in which they proposed two different types of algorithms. The purpose of the present paper is to suggest an improved Spanning Heuristic algorithm. Its improvement increases as the problem size increases. Further results and comparisons are derived for the unordered and ordered cases.This research shows that when the search space is very large, it is better to inquire from items that are known not to be the goal (they have been ruled out by previous guesses), for the purpose of acquiring more information about the goal. As the search space is narrowed, it is better to guess items that have not been ruled out. 相似文献
12.
Douglas L. Bessette Lauren A. Mayer Bryan Cwik Martin Vezér Klaus Keller Robert J. Lempert Nancy Tuana 《Risk analysis》2017,37(10):1993-2004
Individuals use values to frame their beliefs and simplify their understanding when confronted with complex and uncertain situations. The high complexity and deep uncertainty involved in climate risk management (CRM) lead to individuals’ values likely being coupled to and contributing to their understanding of specific climate risk factors and management strategies. Most mental model approaches, however, which are commonly used to inform our understanding of people's beliefs, ignore values. In response, we developed a “Values‐informed Mental Model” research approach, or ViMM, to elicit individuals’ values alongside their beliefs and determine which values people use to understand and assess specific climate risk factors and CRM strategies. Our results show that participants consistently used one of three values to frame their understanding of risk factors and CRM strategies in New Orleans: (1) fostering a healthy economy, wealth, and job creation, (2) protecting and promoting healthy ecosystems and biodiversity, and (3) preserving New Orleans’ unique culture, traditions, and historically significant neighborhoods. While the first value frame is common in analyses of CRM strategies, the latter two are often ignored, despite their mirroring commonly accepted pillars of sustainability. Other values like distributive justice and fairness were prioritized differently depending on the risk factor or strategy being discussed. These results suggest that the ViMM method could be a critical first step in CRM decision‐support processes and may encourage adoption of CRM strategies more in line with stakeholders’ values. 相似文献
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14.
Lifetime Data Analysis - The recurrent/terminal event data structure has undergone considerable methodological development in the last 10–15 years. An example of the data structure that has... 相似文献
15.
Demography - One of the most consistent patterns in the social sciences is the relationship between sibship size and educational outcomes: those with fewer siblings outperform those with many. The... 相似文献
16.
Diana Hernández Yang Jiang Daniel Carrión Douglas Phillips Yumiko Aratani 《Journal of Children and Poverty》2016,22(2):77-92
The costs for rent and utilities account for the largest share of living expenses, yet these two critical dimensions of material hardship have seldom been examined concurrently in population-based studies. This paper employs multivariate statistical analysis using American Community Survey data to demonstrate the relative risk ratio of low-income renter-occupied households with children experiencing ‘rent burden', ‘energy insecurity', or a ‘double burden’ as opposed to no burden. Findings suggest that low-income households are more likely to experience these economic hardships in general but that specific groups are disproportionately burdened in different ways. For instance, whereas immigrants are more likely to experience rental burden, they are less likely to experience energy insecurity and are also spared from the double burden. In contrast, native-born African Americans are more likely than all other groups to experience the double burden. These results may be driven by the housing stock available to certain groups due to racial residential segregation, decisions regarding the quality of housing low-income householders are able to afford, as well as home-country values, such as modest living and energy conservation practices, among immigrant families. This paper also points to important policy gaps in safety net benefits related to housing and energy targeting low-income households. 相似文献
17.
This article examines the concept of career exploration in adult populations. In contrast to the prevailing positive view of career exploration, the authors present a more complex and balanced perspective of this process, addressing some of the barriers to career exploration and the applicability of this concept to different populations. They examine differences between voluntary exploration and forced or chance exploration, discuss how relationships may be barriers to exploration, consider various outcomes of career explorations, and call for a more holistic view of the individual in career counseling. 相似文献
18.
Penicillin and ampicillin drugs are approved for use in food animals in the United States to treat, control, and prevent diseases, and penicillin is approved for use to improve growth rates in pigs and poultry. This article considers the possibility that such uses might increase the incidence of ampicillin-resistant Enterococcus faecium (AREF) of animal origin in human infections, leading to increased hospitalization and mortality due to reduced response to ampicillin or penicillin. We assess the risks from continued use of penicillin-based drugs in food animals in the United States, using several assumptions to overcome current scientific uncertainties and data gaps. Multiplying the total at-risk population of intensive care unit (ICU) patients by a series of estimated factors suggests that not more than 0.04 excess mortalities per year (under conservative assumptions) to 0.14 excess mortalities per year (under very conservative assumptions) might be prevented in the whole U.S. population if current use of penicillin drugs in food animals were discontinued and if this successfully reduced the prevalence of AREF infections among ICU patients. These calculations suggest that current penicillin usage in food animals in the United States presents very low (possibly zero) human health risks. 相似文献
19.
B. Douglas Bernheim Debraj Ray evin Yeltekin 《Econometrica : journal of the Econometric Society》2015,83(5):1877-1911
We argue that poverty can perpetuate itself by undermining the capacity for self‐control. In line with a distinguished psychological literature, we consider modes of self‐control that involve the self‐imposed use of contingent punishments and rewards. We study settings in which consumers with quasi‐hyperbolic preferences confront an otherwise standard intertemporal allocation problem with credit constraints. Our main result demonstrates that low initial assets can limit self‐control, trapping people in poverty, while individuals with high initial assets can accumulate indefinitely. Thus, even temporary policies that initiate accumulation among the poor may be effective. We examine implications concerning the effect of access to credit on saving, the demand for commitment devices, the design of financial accounts to promote accumulation, and the variation of the marginal propensity to consume across income from different sources. We also explore the nature of optimal self‐control, demonstrating that it has a simple and behaviorally plausible structure that is immune to self‐renegotiation. 相似文献
20.
Gary Douglas Rubin 《Business and Society Review》2015,120(4):519-548
This work concerns itself with the debate taking place in the United States about the duty of care financial advisers owe investors. On one side it is argued that advisers need only concern themselves with recommendations which meet certain suitability standards. On the other side, there are those who argue the suitability standard is not strong enough to adequately protect investor interests. Instead of ensuring investment recommendations are merely suitable, financial advisers owe their investors a fiduciary duty to “act in the best interest of the customer without regard to the financial or other interests … of the investment adviser providing the advice.” (SEC, 2011). In applying a properly understood conception of what fiduciary means I argue that regulations should not be harmonized but that fiduciary duty should apply to all who provide personalized investment advice to retail customers. I will further argue that even if the regulations are harmonized as proposed, because of exemptions for broker‐dealers as envisioned in the proposal, and which currently apply to Registered Investment Advisers, the efficacy of fiduciary duty is diluted to the point of rendering its current application, much less its potential uniform imposition, irrelevant. 相似文献