An evaluation of fixed and randomized price sequence on the alcohol purchase task

Presentation matters: Effects of cigarette purchase task design on systematic data and purchasing behavior

Hypothetical purchase tasks (HPTs) are effective tools for evaluating participants' demand for substances. The present study evaluated the effect of task presentation on producing unsystematic data and purchasing behavior in a sample of individuals who smoke cigarettes. Participants (n = 365) were recruited from Amazon Mechanical Turk and randomly assigned to complete two of three HPT presentations: List (prices on one page in an increasing order), Ascending (one price per page in an increasing order), or Random (one price per page in a random order). We evaluated outcomes using a mixed model regression with a random effect for participants. We observed a significant effect of task presentation on passing the criterion assessing consistency in effects of contiguous prices (i.e., Bounce; X²(2) = 13.31, p = .001). A significant effect of task presentation on Trend or Reversals from Zero was not observed. For purchasing behavior, we observed a significant effect of task presentation on R², X²(2) = 17.89, p < .001; BP₁, X²(2) = 13.64, p = .001; ln(α), X²(2) = 332.94, p < .001; and ln(Omax), X²(2) = 20.26, p < .001; we did not observe a significant effect of task presentation on ln(Q₀) or ln(Pmax). We recommend against using the Random HPT presentation to avoid unsystematic data. While the List and Ascending presentations do not differ across unsystematic criteria or purchasing behavior, the List presentation may be preferred due to participant experience. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Reliability and validity of behavioral-economic measures: A review and synthesis of discounting and demand

This review sought to synthesize the literature on the reliability and validity of behavioral-economic measures of demand and discounting in human research, introduce behavioral-economic research methodologies for studying addictive behaviors, discuss gaps in the current literature, and review areas for future research. A total of 34 studies was included in this review. The discounting literature showed similar responding regardless of whether hypothetical or actual outcomes were used, though people tended to discount the outcome presented first more steeply, suggesting order effects. Although delay-discounting measures seem to show temporal stability, exceptions were found for probability- and experiential-discounting tasks. The demand literature also demonstrated similar responding regardless of outcome type; however, some demand indices showed exceptions. Randomized price sequences tended to show modest increases in Omax and α and modestly higher rates of inconsistent or nonsystematic responses compared with sequential price sequences. Demand indices generally showed temporal stability, although the stability was weaker the larger the time interval between test sessions. Future studies would benefit by examining addictive commodities beyond alcohol, nicotine, and money; examining temporal stability over longer time intervals; using larger delays in discounting tasks; and using larger sample sizes.

(Non-) impact of task experience on behavioral economic decision-making

Behavioral economic research has been widely conducted via crowdsourcing resources to evaluate novel task designs or pilot interventions. One under recognized and yet-to-be tested concern is the impact of non-naïvety (i.e., prior task exposure) on behavioral economic task performance. We evaluated the influence of non-naïvety on task performance in two popular areas of behavioral economic research: behavioral economic demand and delay discounting. Participants (N = 485) recruited using Amazon Mechanical Turk (mTurk) completed alcohol and soda purchase tasks and delay discounting tasks for monetary and alcohol outcomes. Equivalence of responding and effect sizes with clinical variables were compared based on prior task experience. Over one quarter of participants reported demand task experience (26.9%) and nearly half endorsed delay discounting task experience (48.6%). Statistically equivalent responding was observed for alcohol purchase task data with less-than-small effect size differences based on task experience (d = 0.01-0.13). Similar results were observed for a soda purchase task thereby supporting generalization to a non-alcohol commodity. Measures of convergent and discriminant validity for behavioral economic demand indicated medium-to-large and stimulus-specific effect sizes with little variation based on prior task exposure. Delay discounting for money and alcohol showed some sensitivity to prior task experience (i.e., less steep discounting for non-naïve participants), however these effects were attenuated after accounting for group differences in alcohol use. These findings support the fidelity of behavioral economic task outcomes and emphasize that participant non-naïvety in crowdsourcing settings may minimally impact performance on behavioral economic assays commonly used in behavioral and addiction science. (PsycInfo Database Record (c) 2022 APA, all rights reserved).