The attractiveness of a reward depends in part on the delay to its receipt, with more distant rewards generally being valued less than more proximate ones. The rate at which people discount the value of delayed rewards has been associated with a variety of clinically and socially relevant human behaviors. Thus, the accurate measurement of delay discounting rates is crucial to the study of mechanisms underlying behaviors such as risky sex, addiction, and gambling. In delay discounting tasks, participants make choices between two alternatives: one small amount of money delivered immediately versus a large amount of money delivered after a delay. After many choices, the experimental task will converge on an indifference point: the value of the delayed reward that approximates the value of the immediate one. It has been shown that these indifference points are systematically biased by the direction in which one of the alternatives adjusts. This bias is termed a sequencing effect.

The present research proposed a reference-dependent model of choice drawn from Prospect Theory to account for the presence of sequencing effects in a delay discounting task. Sensitivity to reference frames and sequencing effects were measured in two computer tasks. Bayesian and frequentist analyses indicated that the reference-dependent model of choice cannot account for sequencing effects. Thus, an alternative, perceptual account of sequencing effects that draws on a Bayesian framework of magnitude estimation is proposed and furnished with some preliminary evidence. Implications for future research in the measurement of delay discounting and sensitivity to reference frames are discussed.

Delay discounting is the decline in the present value of a reward with delay to its receipt. (Mazur,1987). The delay discounting task is used to measure delay discounting rate, which requires the participants to choose between two options: one involves immediate delivery of a reward, and other involves delivery after a delay, and the immediate rewards are adjusted in value until the subject feels there is no difference between the immediate and the delayed reward. Some previous studies (Robles and Vargas, 2007; 2008; Robles et al., 2009) found that the order of presentation of the immediate rewards (ascending or descending) significantly influenced the estimated delay discounting rate, which is known as the order effect. Uncertainty about the future and impulsivity could explain delay discounting behavior. The purpose of this study was to explore the order effect in delay discounting assessment. The current study found that the order effect in the delay discounting task can be explained by risk aversion, loss aversion and impulsivity. In the current study, the two kinds of fixed procedure (ascending and descending), and the titrating delay discounting task were used to estimate the degree of delay discounting. Also, two gambling tasks were applied to measure risk and loss aversion indices. The BIS-11 scale was used to assess the level of trait impulsivity. The results indicated that impulsivity biases individuals to choose the immediate small reward rather than the large delayed reward, resulting in lower area under the discounting curve (AUC) when estimated with the ascending-sequence delay discounting task. Also, impulsivity moderated the relationship between loss aversion and AUC estimated with the descending-sequence delay discounting task.

The value of safe sex may be discounted based on contextual factors associated with an opportunity for sex. College students (n = 75) in a within-subjects study selected hypothetical sexual partners from a set of pictures and classified them based on attractiveness and estimated chance of having an STI. In the sexual delay discounting (SDD) task, participants rated their likelihood (0 – 100%) of waiting for some period of time (e.g., 3 hours) to have protected sex with their selected partners, when they could have immediate sex without protection. In the sexual probability discounting (SPD) task, participants rated their likelihood of having protected sex if the opportunity was uncertain (e.g., 50%), when they could have unprotected sex for sure (100%). All participants included in the final analyses were aware of and had a positive attitude towards protection against STIs as they indicated preference for immediate (or certain) protected sex. Results show that participants’ willingness to have safe sex systematically decreased as the delay to and odds against having safe sex increased. However, these discounting patterns were observed only in some partner conditions but not others, showing that preference for delayed (or uncertain) safe sex was altered by perceived attractiveness and STI risk of sexual partners. Moreover, the hyperbolic discounting model provided good to acceptable fit to the delay and probability discounting data in most-wanted and least-STI conditions. Gender differences in devaluation of safe sex were also found.

Recent research has identified affirmation of transcendence and exposure to violent Bible verses as being related to greater prejudice toward value-violating out-groups (Blogowska & Saroglou, 2012; Shen et al., 2013). Effects of exposure to specific Bible verses on attitudes toward out-groups have not been measured in combination with the Post-Critical Belief Scale developed by Hutsebaut (1996). The relationships between exposure to scriptural endorsements of prejudice, affirmation vs. disaffirmation of transcendence, literal vs. symbolic processing of religious content, and prejudice toward value-violating out-groups were examined using an online survey administered to a sample of U.S. adults (N=283). Greater affirmation of transcendence scores were linked to greater prejudice toward atheists and homosexuals and more favorable ratings of Christians and highly religious people. Lower affirmation of transcendence scores were linked to less favorable ratings of Christians and highly religious people and more favorable ratings of atheists. Exposure to scriptural endorsements of prejudice did not have a significant effect on levels of prejudice in this study.