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1.
We study how experimental subjects report subjective probability distributions in the presence of ambiguity characterized by uncertainty over a fixed set of possible probability distributions generating future outcomes. Subjects observe draws from the true but unknown probability distribution generating outcomes at the beginning of each period of the experiment and state at selected periods a) the likelihoods that each probability distribution in the set is the true distribution, and b) the likelihoods of future outcomes. We estimate heterogeneity of rules used to update uncertainty about the true distribution and rules used to report distributions of future outcomes. We find that approximately 65% of subjects report distributions by properly weighing the possible distributions using their expressed uncertainty over them, while 22% of subjects report distributions close to the distribution they perceive as most likely. We find significant heterogeneity in how subjects update their expressed uncertainty. On average, subjects tend to overweigh the importance of their prior uncertainty relative to new information, leading to ambiguity that is substantially more persistent than would be predicted using Bayes’ rule. Counterfactual simulations suggest that this persistence will likely hold in settings not covered by our experiment.  相似文献   

2.
This paper investigates whether preferences over environmental risks are best modeled using probability-weighted utility functions or can be reasonably approximated by expected utility (EU) or subjective EU models as is typically assumed. I elicit risk attitudes in the financial and environmental domains using multiple-price list experiment. I examine how subjects?? behavioral, attitudinal, and demographic characteristics affect their probability weighting functions first for financial risks, then for oil-spill risks. I find that most subjects tend to overweight extreme positive outcomes relative to expected utility in both the environmental and financial domains. Subjects are more likely to overemphasize low probability, extreme environmental outcomes than low probability, extreme financial outcomes, leading subjects to offer more support for mitigating environmental gambles than financial gambles with the same odds and equivalent outcomes. I conclude that EU models are likely to underestimate subjects?? willingness to pay for environmental cleanup programs or policies with uncertain outcomes.  相似文献   

3.
We studied how evaluation of changes in low-probability risks are affected by reference points and framing effects. Subjects considered hypothetical situations with one or two low-probability risks. Different frames were used to describe changes in risk levels. In the first experiment, subjects chose between risk-reduction options that achieved the same overall risk reduction: large reduction of one risk vs. equal (smaller) reduction of two risks. When the risks were described as losses relative to the no-risk ideal, more subjects were indifferent between the options than when the same options were described as gains relative to the status quo. In the latter case subjects preferred equal reduction of both risks, unless one risk could be reduced to zero. In a related experiment, subjects were less willing to pay any price for a commodity that carried small increases in two risks than for a commodity carrying a comparable large increase in one risk. In other experiments, subjects evaluated single changes in risks rather than comparing or evaluating pairs of changes. Subjects again placed particularly high value on reducing any risks to zero, and they were even more inclined to do so when some other risk would also be reduced to zero. In a final experiment, elimination of risk was found to be less highly valued if its source was not fully eliminated, and a status-quo effect was found. The findings are interpreted in terms of reference theories of choice.  相似文献   

4.
A ‘bonus culture’ among financial traders has been blamed for the excessive risk-taking in the run-up to the latest financial crisis. I show that when individuals are more social gain seeking than social loss averse (i.e. gloating is stronger than envy), social comparison predicts more risk-taking as well as a preference for negatively correlated gambles. Testing these two joint propositions in a laboratory experiment, I find that preference for positively or negatively correlated outcomes is highly correlated with risk-taking in a social risky investment task. While only a third of subjects prefer negatively correlated outcomes in a peer comparison setting, in line with relatively stronger social gain seeking, those subjects invest on average 50 % more in a risky gamble in their peer comparison setting than a reference group that made the same decision in an isolated individual setting. Subjects with a preference for positively correlated outcomes, in line with relatively stronger social loss aversion, do not show a higher propensity to invest in a risky gamble compared to the individual reference group.  相似文献   

5.
Bias toward the status quo, found in choice and in emotional reactions to adverse outcomes, has been confounded with bias toward omission. We unconfounded these effects with scenarios in which change occurs unless action is taken. Subjects reacted more strongly to adverse outcomes caused by action, whether the status quo was maintained or not, and subjects preferred inaction over action even when inaction was associated with change. No status-quo bias was found in a matching task, which did not require action. The observed status-quo bias is at least partly caused by a bias toward omissions.  相似文献   

6.

Discounted utility theory and its generalizations (e.g., quasihyperbolic discounting, generalized hyperbolic discounting) use discount functions for weighting utilities of outcomes received in different time periods. We propose a new simple test of convexity–concavity of discount function. This test can be used with any utility function (which can be linear or not) and any preferences over risky lotteries (expected utility theory or not). The data from a controlled laboratory experiment show that about one third of experimental subjects reveal a concave discount function and another one third of subjects reveal a convex discount function (for delays up to two month).

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7.
One fundamental assumption often made in the literature on unawareness is that risk preferences are invariant to changes of awareness. We study how exposure to unawareness affects choices under risk. Participants in our experiment choose repeatedly between varying sure outcomes and a lottery in three phases. All treatments are exactly identical in phase 1 and phase 3, but differ in phase 2. There are five different treatments pertaining to the lottery faced in phase 2: The control treatment (i.e., a standard lottery), the treatment with awareness of unawareness of lottery outcomes but known number of outcomes, the treatment with awareness of unawareness of outcomes but with unknown number of outcomes, the treatment with unawareness of unawareness of some outcomes, and the treatment with an ambiguous lottery. We study both whether behavior differs in phase 3 across treatments (between subjects effect) and whether differences of subjects’ behavior between phases 1 and phase 3 differ across treatments (within subject effects). We observe no significant treatment effects.  相似文献   

8.
Orphan and vulnerable children (OVC) often have worse educational, developmental, nutritional, and behavioral outcomes than non‐OVC. Much of these disparities come from reduced household earnings due to the loss of parental income. The present study used conditional process analysis to evaluate income and savings among OVC households, using cross‐sectional data from 1,060 OVC in a 3‐year Kenyan empowerment program that combined elements of cash transfer, psychosocial support, and small business entrepreneurship. Higher monthly earnings were significantly associated with program participation in a graded fashion. Approximately one‐third of the association was mediated by material inputs, indicating that a substantial portion may be explained by other unobserved program elements. Eighty‐five percent of increased rates of saving money in the past year were mediated by improved monthly income, cash transferred and improved food consumption. Data analysis highlights the need for multisectoral approaches and the need for more research to understand how to improve household economic stability among OVC. Key Practitioner Message: ? Orphans and vulnerable children (OVC) are at risk of greater poverty, leading to multiple developmental and health challenges; ? Current policy in Kenya to offset costs of caring for OVC utilizes monthly cash transfers to households providing care for OVC; ? The present study found that increases in monthly income in an OVC multisectoral empowerment program were largely due to factors beyond the material inputs.  相似文献   

9.
This paper formulates and axiomatizes utility models for denumerable time streams that make no commitment in regard to discounting future outcomes. The models address decision under certainty and decision under risk. Independence assumptions in both contexts lead to additive or multiplicative utilities over time periods that allow unambiguous comparisons of the relative importance of different periods. The models accommodate all patterns of future valuation. This discount-neutral feature is attained by restricting preference comparisons to outcome streams or probability distributions on outcome streams that differ in at most a finite number of periods.  相似文献   

10.
This paper reports the results of experiments designed to test the effect of experience on preferences for self-protection against low and high probability losses. Subjects gained experience by repeatedly making choices about whether or not to invest in a protective activity and then observing the result of their choice. Half of the subjects faced a low probability risk while the other half faced a higher probability risk with the severity of loss scaled down to hold expected value constant. Protection was more common against the high probability risk. Despite receiving full information about the risks in advance, most subjects made choices in response to prior outcomes. This led to a great deal of experimentation when losses were common (the high probability risk) but very little experimentation when losses were infrequent (the low probability risk).  相似文献   

11.
We conduct an experiment on individual choice under risk in which we study belief updating when an agent receives a signal that restricts the number of possible states of the world. Subjects observe a sample drawn from an urn and form initial beliefs about the urn??s composition. We then elicit how beliefs are modified after subjects receive a signal that restricts the set of the possible urns from which the observed sample could have been drawn. We find that this type of signal increases the frequency of correct assessments and that prediction accuracy is higher for lower levels of risk. We also show that prediction accuracy is higher after invalidating signals (i.e. signals that contradict the initial belief). This pattern is explained by the lower level of risk associated with invalidating signals. Finally, we find evidence for a lack of persistence of choices under high risk.  相似文献   

12.
We conduct experiments to analyze investment behavior in decisions under risk. Subjects can bet on the outcomes of a series of coin tosses themselves, rely on randomized ‘experts’, or choose a risk-free alternative. We observe that subjects who rely on the randomized experts pick those who were successful in the past, showing behavior consistent with the hot hand belief. Obviously the term ‘expert’ suffices to attract some subjects. For those who decide on their own, we find behavior consistent with the gambler’s fallacy, as the frequency of betting on heads (tails) decreases after streaks of heads (tails).  相似文献   

13.
This short‐term longitudinal study examined relations between emotion knowledge and social functioning in a sample of low‐income kindergarten and 1st graders. Individual differences in spontaneous emotion naming and emotion recognition skills were used to predict children's social functioning at school, including peer‐nominated sociometric status, and child self‐reports of negative experiences with peers in school (peer victimization and rejection). Children who had greater emotional vocabulary and recognized emotions more accurately had better outcomes in all areas, and many of the associations between fall emotion knowledge skills and spring social functioning outcomes held after covarying grade and children's previous status with regard to these outcomes. Results are discussed with regard to implications for prevention and intervention programs (e.g., the PATHS curriculum) that focus on teaching emotion knowledge skills in order to foster high‐risk children's social competence.  相似文献   

14.
India's demographic trends portend moderately rapid ageing of the population. This, combined with the limited coverage of pension and health care programmes in terms of population, types of risks covered, and benefit levels has led to greater urgency in extending the coverage and reform directions of the current pension and health care programmes. This article analyses three pension and health care initiatives in India directed at the workers and their families engaged in the informal sector. The first initiative, India's National Social Assistance Programme (NSAP), undertaken in 1995 provides budget‐financed transfers targeted at older persons. It is funded by the Union government but implemented by the state governments. The second initiative, called Swavalamban, was started in 2010, but has been subsumed under Atal Pension Yojana (APY), in the 2015–16 budget. Both are voluntary co‐contributory initiatives aimed at providing access to retirement income to low‐income individuals (government co‐contributing with the individual). Unlike Swavalamban, the APY initiative has provisions for minimum guaranteed pension benefits, with contributions required by the members adjusted accordingly. Effectiveness in increasing enrollment and in sustaining contributions over a longer period will impact on the extent of retirement income security obtained by the members. The third initiative, Rashtriya Swasthya Bima Yojana (RSBY), is insurance‐based and aims to provide hospital care to low‐income households. The article argues that for improving outcomes of these initiatives, more effective implementation, greater fiscal resources, and an integrated and systemic approach which is aided by technology‐enabled platforms such as Aadhaar, will be needed.  相似文献   

15.
We report results of an experiment testing for present-value maximization in intertemporal income choice. Two-thirds of subjects did not maximize present value. Through a series of experimental manipulations that impose costs on non-present value maximizers, we are able to reduce the level of violations substantially. We find, however, that a sizeable proportion of subjects continue to systematically violate present-value principles. Our interpretation is that these subjects either cannot or choose not to distinguish between t income and t expenditure in making their choices. Self-management, bounded rationality, and sequence preference are suggested as possible explanations for such behavior.  相似文献   

16.
We use the multiple price list method and a recursive expected utility theory of smooth ambiguity to separate out attitude towards risk from that towards ambiguity. Based on this separation, we investigate if there are differences in agent behaviour under uncertainty over gain amounts vis-a-vis uncertainty over loss amounts. On an aggregate level, we find that (i) subjects are risk averse over gains and risk seeking over losses, displaying a “reflection effect” and (ii) they are ambiguity neutral over gains and are mildly ambiguity seeking over losses. Further analysis shows that on an individual level, and with respect to both risky and ambiguous prospects, there is limited incidence of a reflection effect where subjects are risk/ambiguity averse (seeking) in gains and seeking (averse) in losses, though this incidence is higher for ambiguous prospects. A very high proportion of such cases of reflection exhibit risk (ambiguity) aversion in gains and risk (ambiguity) seeking in losses, with the reverse effect being significantly present in the case of risk but almost absent in case of ambiguity. Our results suggest that reflection across gains and losses is not a stable individual characteristic, but depends upon whether the form of uncertainty is precise or ambiguous, since we rarely find an individual who exhibits reflection in both risky and ambiguous prospects. We also find that correlations between attitudes towards risk and ambiguity were domain dependent.   相似文献   

17.
ABSTRACT

This study investigated the impact of Head Start, disability status, and receipt of an Individualized Education Program (IEP) on early language, literacy, and mathematics skills for low-income children with language, cognitive, emotional/behavioral, sensory, and physical disabilities. Secondary analysis of data was performed on a sample of children with disabilities (N = 570) drawn from the Head Start Impact Study, a nationally representative study of approximately 5,000 children randomly assigned to Head Start or non–Head Start programs. Results of ordinary least squares regression analyses indicated that Head Start participation enhanced outcomes for children with multiple disabilities; language, literacy, and mathematics skills at age 5–6 years were higher for these children compared to non–Head Start attendees. Head Start children with disabilities were more likely to have an IEP, though IEP receipt was associated with lower language, literacy, and mathematics scores among all children. There is a need to ensure that Head Start, and programs similar to Head Start, are more widely available to provide comprehensive, quality early childhood programming to children with cumulative risk factors (low income, multiple disabilities). Future research should clarify why IEP receipt was associated with poorer cognitive outcomes.  相似文献   

18.
The concentration of high-frequency controls in a limited period of time (“crackdowns”) constitutes an important feature of many law-enforcement policies around the world. In this paper, we offer a comprehensive investigation on the relative efficiency and effectiveness of various crackdown policies using a lab-in-the-field experiment with real passengers of a public transport service. We introduce a novel game, the daily public transportation game, where subjects have to decide, over many periods, whether to buy or not a ticket knowing that there might be a control. Our results show that (a) concentrated crackdowns are less effective and efficient than random controls; (b) prolonged crackdowns reduce fare-dodging during the period of intense monitoring but induce a burst of fraud as soon as they are withdrawn; (c) pre-announced controls induce more fraud in the periods without control. Overall, we also observe that real fare-dodgers fraud more in the experiment than non-fare-dodgers.  相似文献   

19.
This study tested the hypothesis that the effects of income and cumulative risk on the development of effortful control during preschool would be mediated by parenting. The study utilized a community sample of 306 children (36–40 months) representing the full range of family income, with 29 percent at or near poverty and 28 percent lower income. Two dimensions of effortful control (executive control and delay ability) were assessed at four time points, each separated by nine months, and growth trajectories were examined. Maternal warmth, negativity, limit setting, scaffolding, and responsiveness were observed. Above the effects of child cognitive ability, income, and cumulative risk, scaffolding predicted higher initial levels of executive control that remained higher across the study, and limit setting predicted greater gains in executive control. Parenting did not predict changes in delay ability. Significant indirect effects indicated that scaffolding mediated the effects of income and cumulative risk on growth in executive control. The findings suggest that parenting behaviors can promote effortful control in young children and could be targets of prevention programs in low‐income families.  相似文献   

20.

This paper experimentally investigates the altruistic behavior of physicians and whether this behavior is affected by payment system and uncertainty in health outcome. Subjects in the experiment take on the role of physicians and decide on the provision of medical care for different types of patients, who are identical in all respects other than the degree to which a given level of medical treatment affects their health. We investigate physician altruism from the perspective of ethical principles, by categorizing physicians according to how well their treatment decisions align with different principles for priority setting. The experiment shows that many physicians are altruistic toward their patients but also that the degree of altruism varies across patients with different medical needs. We find a strong effect of payment system that is overall unaffected by the introduction of risk and ambiguity in patients’ health outcomes. There is, however, substantial heterogeneity across individuals, in particular under the capitation payment system where physicians’ responses to the introduction of uncertainty in patient health are modulated by their own generic risk and ambiguity preferences.

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