Subjective beliefs and economic preferences during the COVID-19 pandemic.

The COVID-19 pandemic presents a remarkable opportunity to put to work all of the research that has been undertaken in past decades on the elicitation and structural estimation of subjective belief distributions as well as preferences over atemporal risk, patience, and intertemporal risk. As contributors to elements of that research in laboratories and the field, we drew together those methods and applied them to an online, incentivized experiment in the United States. We have two major findings. First, the atemporal risk premium during the COVID-19 pandemic appeared to change significantly compared to before the pandemic, consistent with theoretical results of the effect of increased background risk on foreground risk attitudes. Second, subjective beliefs about the cumulative level of deaths evolved dramatically over the period between May and November 2020, a volatile one in terms of the background evolution of the pandemic. Supplementary Information: The online version contains supplementary material available at 10.1007/s10683-021-09738-3.

Eliciting Beliefs about COVID-19 Prevalence and Mortality: Epidemiological Models Compared with The Street.

Subjective belief elicitation about uncertain events has a long lineage in the economics and statistics literatures. Recent developments in the experimental elicitation and statistical estimation of subjective belief distributions allow inferences about whether these beliefs are biased relative to expert opinion, and the confidence with which they are held. Beliefs about COVID-19 prevalence and mortality interact with risk management efforts, so it is important to understand relationships between these beliefs and publicly disseminated statistics, particularly those based on evolving epidemiological models. The pandemic provides a unique setting over which to bracket the range of possible COVID-19 prevalence and mortality outcomes given the proliferation of estimates from epidemiological models. We rely on the epidemiological model produced by the Institute for Health Metrics and Evaluation together with the set of epidemiological models summarised by FiveThirtyEight to bound prevalence and mortality outcomes for one-month, and December 1, 2020 time horizons. We develop a new method to partition these bounds into intervals, and ask subjects to place bets on these intervals, thereby revealing their beliefs. The intervals are constructed such that if beliefs are consistent with epidemiological models, subjects are best off betting the same amount on every interval. We use an incentivised experiment to elicit beliefs about COVID-19 prevalence and mortality from 598 students at Georgia State University, using six temporally-spaced waves between May and November 2020. We find that beliefs differ markedly from epidemiological models, which has implications for public health communication about the risks posed by the virus.

Willpower without risk?

Ainslie does not formally incorporate risk and uncertainty in his framework for modelling impulses and willpower. To provide a complete account of the motivational bases of choice behaviour, Ainslie should extend his framework to incorporate risk attitudes and subjective beliefs.

Fixed Attributes and Discounting Behavior.

Delay discounting tasks present alternatives that differ in two attributes: amount and delay. Typically, choice is modeled by application of a discount function to each option, allowing alternative-wise comparison. However, if participants make decisions by comparing attributes, manipulations that affect the salience of either attribute may affect patience. In Experiment 1, participants completed one block of trials in which amount was a fixed attribute (constant across trials), and another in which delay was fixed. Consistent with the hypothesis that the varying attribute would be more salient, participants exhibited less patience in the amount-fixed condition. Moreover, this effect was larger for participants who responded more quickly when making choices that favored the varying attribute. In Experiment 2, these findings were extended by adding trial blocks with a working memory dual task. We replicated the fixed-attribute effect, along with the aforementioned association with reaction time. Contrary to expectation, the fixed-attribute effect was not larger when participants were under working memory load. Instead, working memory load was associated with more patient responses, which may be related to idiosyncrasies of the task including the absence of immediate rewards. Overall, results suggest a fixed-attribute effect on patience, which is consistent with a multi-attribute decision framework.

Incentivizing university students to quit smoking: a randomized controlled trial of a contingency management intervention in a developing country.

Background: Contingency management (CM) is an empirically supported behavioral treatment for tobacco use, but its efficacy with university student smokers in a developing country is unknown. Objectives: We evaluate a randomized controlled trial of a CM smoking cessation program conducted on a sample of treatment-seeking student smokers at the University of Cape Town.Methods: The study included a recruitment period, a 6-week intervention period, and a 6-month follow-up period. Subjects in the control group (information and monitoring; n = 47, 76% male) were given information to help them quit smoking and had their quit attempt monitored, receiving R50 ($8) at each assessment. Subjects in the treatment group (information and monitoring, plus CM; n = 40, 80% male) could additionally earn R150 ($24) in abstinence-contingent incentives at each assessment. Outcome variables: 7-day point-prevalence abstinence at 6 months and at the end of the intervention period, and a repeated measure of smoking intensity of non-abstinent subjects.Results: CM had no long-term effect on abstinence at 6 months but had a marked and statistically significant effect on the likelihood of abstinence by the end of the intervention period (p < .001). In addition, while CM did not affect smoking intensity, participation in the program decreased the average number of cigarettes smoked per day by non-abstainers (p < .001).Conclusions: The CM program was efficacious in promoting abstinence amongst treatment-seeking university students in a developing country but only while incentives were in place. Future research should focus on promoting continuous abstinence with this target sample.

Mixture models of delay discounting and smoking behavior.

BACKGROUND: Smokers exhibit an unusually high willingness to forgo a delayed reward of greater magnitude to receive a smaller, more immediate reward. The functional form of such "delay discounting" behavior is central to the discounting-based operationalization of impulsivity, and has implications for theories regarding the basis of steep discounting among smokers and treatment approaches to addiction. OBJECTIVES: We examined the discounting behavior of current smokers, ex-smokers, and never-smokers to determine whether the functional form of discounting differs between these groups. METHODS: Participants completed a 27-item delay discounting questionnaire (25). We used finite mixture modeling in analyzing data as the product of two simultaneous data-generating processes (DGPs), a hyperbolic function and an exponential function, and compared results to a quasi-hyperbolic (QH) approximation, in a relatively large sample (n = 1205). RESULTS: Consistent with prior reports, current smokers exhibited steeper discounting relative to never-smokers across exponential, hyperbolic, and QH models. A mixture model provided significant support for exponential and hyperbolic discounting in the data, and both accounted for roughly 50% of the participants' choices. This mixture model showed a statistically significantly better fit to the data than the exponential, hyperbolic, or QH functions alone. Contrary to the prevailing view, current smokers were not more likely to discount hyperbolically than nonsmokers, and, thus, were not more prone to time-inconsistent discounting. CONCLUSIONS: The results inform the interpretation of steep discounting among smokers and suggest that treatment approaches could be tailored to the type of discounting behavior that smokers exhibit.

First Evidence of Comorbidity of Problem Gambling and Other Psychiatric Problems in a Representative Urban Sample of South Africa.

We investigate the extent to which problem gambling in a recent South African sample, as measured by the Problem Gambling Severity Index (PGSI), is comorbid with depression, anxiety and substance abuse. Data are from the 2010 South African National Urban Prevalence Study of Gambling Behavior. A representative sample of the urban adult population in South Africa (N = 3,000). Responses to the 9-item PGSI and ratings on the Beck Depression Index, the Beck Anxiety Inventory, and the World Health Organization Alcohol, Smoking and Substance Involvement Screening Tool (WHO ASSIST). Cross tabulations and Chi square analyses along with logistic regression analyses with and without controls for socio-demographic and/or socio-economic variables were used to identify comorbidities. The prevalence of depression, anxiety, alcohol and substance use were clearly higher among the sample at risk for problem gambling. Black African racial status and living in areas characterized by migrant mining workers was associated with increased risk of problem gambling and comorbidities. There is strong evidence that findings of comorbidities between pathological gambling and depression, anxiety and substance abuse in developed countries generalize to the developing country of South Africa. Historical context, however, gives those comorbidities a unique demographic distribution.

A taxometric analysis of problem gambling data from a South African national urban sample.

We investigate the question whether problem gambling (PG) in a recent South African sample, as measured by the Problem Gambling Severity Index (PGSI), is dimensional or categorical. We use two taxometric procedures, Mean Above Minus Below A Cut (MAMBAC) and Maxim Covariance (MAXCOV), to investigate the taxonic structure of PG as constructed by the PGSI. Data are from the 2010 South African National Urban Prevalence Study of Gambling Behavior. A representative sample of the urban adult population in South Africa (N = 3,000). Responses are to the 9 item PGSI. MAMBAC provided positive but modest evidence that PG as measured by the PGSI was taxonic. MAXCOV pointed more strongly to the same conclusion. These analyses also provide evidence that a PGSI cutoff score of 10 rather than the standard 8 may be called for. PG as constructed by the PGSI may best be thought of as categorical, but further studies with more theory based measurements are needed to determine whether this holds in a wider range of samples and for other screens. A higher cutoff score may be called for on the PGSI when it is used for research purposes to avoid false positives.

Gambling participation and problem gambling severity among rural and peri-urban poor South African adults in KwaZulu-Natal.

Poor South Africans are significantly poorer and have lower employment rates than the subjects of most published research on gambling prevalence and problem gambling. Some existing work suggests relationships between gambling activity (including severity of risk for problem gambling), income, employment status and casino proximity. The objective of the study reported here is to establish the prevalence of gambling, including at risk and pathological gambling, and the profile of gambling activities in two samples of poor South African adults living in a rural and a peri-urban community. A total of 300 (150 male, 150 female) adults in KwaZulu-Natal, South Africa in communities selected using census data, completed the Problem Gambling Severity Index and a survey of socioeconomic and household information, and of gambling knowledge and activity. It was found that gambling was common, and-except for lottery participation-mostly informal or unlicensed. Significant differences between rural and peri-urban populations were found. Peri-urban subjects were slightly less poor, and gambled more and on a different and wider range of activities. Problem and at risk gamblers were disproportionately represented among the more urbanised. Casino proximity appeared largely irrelevant to gambling activity.

An item response theory analysis of the Problem Gambling Severity Index.

Increases in the availability of gambling heighten the need for a short screening measure of problem gambling. The Problem Gambling Severity Index (PGSI) is a brief measure that allows for the assessment of characteristics of gambling behavior and severity and its consequences. The authors evaluate the psychometric properties of the PGSI using item response theory methods in a representative sample of the urban adult population in South Africa (N = 3,000). The PGSI items were evaluated for differential item functioning (DIF) due to language translation. DIF was not detected. The PGSI was found to be unidimensional, and use of the nominal categories model provided additional information at higher values of the underlying construct relative to a simpler binary model. This study contributes to the growing literature supporting the PGSI as the screen of choice for assessing gambling problems in the general population.

The relationship between addiction and reward bundling: an experiment comparing smokers and non-smokers.

AIMS: Previous studies indicate that addicts show reduced preference for more delayed versus more immediate rewards compared to non-addicts. This may reflect a lower propensity to view such decisions in terms of the larger sequences to which they typically belong (e.g. smoking is a frequently repeated act). Therefore, this study aims to test whether, in a sequence of decisions involving smaller, sooner (SS) versus larger, later (LL) rewards, suggesting or forcing people with a propensity to addiction to make the decision for the series as a whole would increase LL preference. It is hypothesized that people without a propensity to addiction should benefit less from being encouraged to think of reward sequences because they already tend to take that view. DESIGN: Thirty regular smokers (as exemplars of addicted individuals) and 30 non-smokers chose between small short-term and larger long-term monetary rewards over a sequence of four decisions spaced 2 weeks apart. Subjects were divided into three groups: one who made each decision independently with no suggestion that they be considered as a series ('free'), a group to whom it was suggested from the start that they consider each decision as part of the series ('suggested') and a group who were told that their very first choice in the series would be used for the remaining decisions ('forced'). All subjects were paid the amounts they had chosen. SETTING: A laboratory room at the University of Cape Town (UCT). PARTICIPANTS: UCT undergraduate volunteers. ANALYSES: The proportion of LL choices in each subgroup was evaluated by χ(2) tests and a probit model. FINDINGS: Smokers increased their preference for LL rewards when 'bundling' of individual decisions into a sequence was either suggested or forced. This preference increased with repeated experience. Non-smokers showed neither pattern. CONCLUSIONS: The propensity of smokers to prefer small short-term rewards over larger delayed rewards may be mitigated, over a sequence of decisions of this kind, by encouraging or forcing them to think of the sequence as a whole. If replicated, this finding may form the basis of an intervention that could attenuate the choice patterns characteristic of addiction.