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971.
We consider kernel methods to construct nonparametric estimators of a regression function based on incomplete data. To tackle the presence of incomplete covariates, we employ Horvitz–Thompson-type inverse weighting techniques, where the weights are the selection probabilities. The unknown selection probabilities are themselves estimated using (1) kernel regression, when the functional form of these probabilities are completely unknown, and (2) the least-squares method, when the selection probabilities belong to a known class of candidate functions. To assess the overall performance of the proposed estimators, we establish exponential upper bounds on the \(L_p\) norms, \(1\le p<\infty \), of our estimators; these bounds immediately yield various strong convergence results. We also apply our results to deal with the important problem of statistical classification with partially observed covariates.  相似文献   
972.
973.
This paper complements evidence on the Allais paradox from advanced countries and educated people by a novel investigation in a poor rural area. The share of Allais-type behavior is indeed high and related to indicators of “lacking ability,” such as poor education, unemployment, and little financial sophistication. Based on prospective reference theory, we extend these characteristics by biased processing of probabilistic information. Finally, we reveal that Allais-type behavior is linked to risk-related characteristics, such as risk tolerance and optimism. This indicates a potential problem as exactly the more dynamic among the poor tend to make inconsistent decisions under uncertainty.  相似文献   
974.
This paper studies the relationship between people’s ambiguity attitudes and income in the field using language as a natural source of ambiguity. It shows that the method of Baillon et al. (2017b) can be adapted for field studies, providing ambiguity measurement tasks that are more comprehensible for nonacademic subjects. Ambiguity attitudes were elicited in two groups of Chinese adolescents (poor rural and rich urban), among whom the income variation is big. In the rural group the poorer are both more ambiguity averse and more a-insensitive, whereas in the urban group the richer are more a-insensitivite. On average, the poor rural adolescents are worse at dealing with ambiguity than their urban counterparts. A-insensitivity, which measures people’s understanding of an ambiguous situation, is an important but sometimes neglected component of ambiguity attitude. Policies aiming to help people improve decisions may focus more on reducing a-insensitivity as this cognitive bias is more likely to be influenced by intervention than people’s intrinsic aversion towards ambiguity.  相似文献   
975.
Some insurance markets are characterized by “advantageous selection”, that is, ex-post risk and coverage are negatively correlated. We show that expectation-based loss aversion as in K?szegi and Rabin (Quarterly Journal of Economics, 121(4), 1133–1165, 2006; The American Economic Review, 97(4), 1047–1073, 2007) provides a natural explanation for this phenomenon in environments in which risk aversion models do not, e.g., when agents face modest-scale risks and/or in absence of moral hazard. More exposure to risk has two competing effects on an agent’s willingness to pay for insurance: a positive effect, as in standard expected utility models; and a negative one, due to a reference effect. We determine conditions under which an insurance provider optimally sets a high price at which only low risk agents buy.  相似文献   
976.
Decisions about how to share resources with others often need to be taken under uncertainty regarding its allocational consequences. Although risk preferences are likely important, existing research is silent about how social and risk preferences interact in such situations. In this paper we provide experimental evidence on this question. In a first experiment givers are not exposed to risk while beneficiaries’ final earnings may be larger or smaller than the allocation itself, depending on the realized state of the world. In a second experiment, risk affects the earnings of givers but not of beneficiaries. We find that individuals’ risk preferences are predictive for giving in both experiments. Increased risk exposure of beneficiaries tends to decrease giving whereas increased risk exposure of givers has no effect. We propose a simple non-linear generalization of a model allowing for other-regarding preferences, ex-post and ex-ante fairness, and risk aversion. We find some support for it in our data when risk is on the beneficiaries’ side but less so when risk is on the givers’ side. Our results point to the importance of the further development of models of social preferences that also incorporate risk preferences.  相似文献   
977.
Current research on how adolescents cope with bullying is primarily quantitative, examines youth in Grades 1 through 6, and neglects to specifically assess how victims of bullying cope with being bullied. The current qualitative study explored the coping strategies of 22 rural middle- and high-school youth victimized by bullying. Results indicated that youth report using an array of emotion focused coping strategies (an internal coping strategy that focuses on emotion regulation) and problem focused coping strategies (active behaviors that are aimed to decrease or eradicate the stressor). These coping strategies included help seeking, physical and verbal aggression, standing up for themselves, and prosocial bystander behavior. While the majority of coping strategies were similar between middle- and high-school participants, these groups reported utilizing verbal and physical aggression in different ways. Further, certain coping strategies, such as help seeking and lashing out with physical and verbal aggression, were utilized as both emotion- and problem-focused coping strategies. Implications are discussed.  相似文献   
978.
In 2011 6.4 million children in the United States ages four to 17 years had a diagnosis of ADHD. Quantitative studies have indicated that parenting stress for parents of children diagnosed with ADHD is high. The purpose of the current meta-synthesis was to conduct a comprehensive review of both the published and unpublished qualitative studies involving the experience of parents raising children diagnosed with ADHD. Searches in online scholarly databases yielded an initial 1217 hits, which were narrowed down to eighty studies that met the criteria. A “meta-ethnography” framework was used for the synthesis. Results of the first part of the analysis were reported in Corcoran et al. (2016) and had to do with the personal impact on parents. The themes in Part II have to do with the processes parents go through in accepting the diagnosis of ADHD and in deciding whether their children should take medication. Parents struggled to make sense of their child’s problems and came to terms with the diagnosis in a series of stages. Regarding medication use, parental attitudes varied greatly, with both costs and benefits noted. Though there was considerable ambivalence towards medication use, some parents reported relief after their child began using medication. Implications from this study are that providers should recognize the processes involved in making decisions about an ADHD diagnosis and the use of medication. Social workers should allow sensitive exploration of parents’ attributions and understanding of their children’s behavior and level of acceptance of the diagnosis. Keeping an ethical and critical stance toward the use of medication, social workers should also have full exploration with parents around the potential benefits and risks associated with the treatment of their children’s ADHD, taking into account parents’ preferences.  相似文献   
979.
Although some research literature focuses on the integration of mental health and career counseling, there has been little that examines both areas in relation to depression and hopelessness. This study investigated the relationship among dysfunctional career thinking, depression, and hopelessness in a sample of 139 undergraduate and graduate students seeking drop‐in or individual career counseling services at a university career center. The authors found that two aspects of dysfunctional career thinking, decision‐making confusion and commitment anxiety, accounted for a significant amount of variance in depression. Decision‐making confusion also accounted for a significant amount of variance in hopelessness. Implications for counseling practice include the need for more careful screening of career clients who present with high levels of anxiety and negative thinking. Future research could involve more diverse client populations, such as unemployed adults, and explore the use of additional screening measures to assess the intersection of career and mental health issues.  相似文献   
980.
Contemporary Colombian conjuncture encompasses two dynamics. These incorporate social, economic, political and cultural aspects, whose related rationalities are yet to be mapped out and understood in their complex and multi-layered dimensions and registers. On the one hand, as I will explain throughout the text, we have been witness to on-going peace talks between the government and the Fuerzas Armadas Revolucionarias de Colombia guerrilla group, a whole set of practices of forgiveness, inaugurations of memory museums, the passing of the victims and land restitution law, as well as the recognition of victims and the effervescence of their movements and organizations. These factors have spiralled victims’ demonstrations and fuelled marches all over the country. On the other hand, there are increased rates of foreign investment in those regions that, until as little as a decade ago, were subject to appalling rates of internal displacement, massacres and disappearances, and which now constitute new borders where global capitalism has been able to reconfigure and increase its rates of capital accumulation. In this article, I analyse the processes referred to above and their complex relationships from the vantage point of a cultural studies interrogation of the affective and the popular, focusing on two Colombian regions: Montes de María and Mapiripán. My goal is to understand how different groups and actors are experiencing these processes in their everyday lives. Here, I include victims and their organizations but also government officials and entrepreneurs related to agro-industry initiatives – mentioned below – today refashioned within the new mantra of corporate responsibility. I want to understand the issue of where people are located and what they are doing, facing, consuming, or resisting in terms of these new challenges. Finally, I wish to offer an analytical study that can capture the everyday textures of these processes in a complex and concrete fashion.  相似文献   
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