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Most current models of delay discounting multiply the nominal value of a good whose receipt is delayed, by a discount factor that is some function of that delay. This article reviews the logic of a theory that discounts the utility of delayed goods by adding the utility of the good to the disutility of the delay. In limiting cases it approaches other familiar models, such as hyperbolic discounting. In nonlimit cases it makes different predictions, generally requiring, inter alia, a magnitude effect when the value of goods is varied. A different theory is proposed for conditioning experiments. In it utility is computed as the average reinforcing strength of the stimuli that signal the delay. Both theories are extended to experiments in which degree of preference is measured, rather than adjustment to iso‐utility values.

If a repeated gamble is subjectively structured into units each consisting of a string of consecutive losses followed by a single win, longer strings will necessarily be less valuable. Longer, less valuable strings will be discounted by delay more than will shorter, more valuable strings. This implies that the whole gamble's expected, delay‐discounted value will increase as delay discounting increases. With this restructuring, even games of (objectively) negative expected value, such as those at casinos, may be subjectively positive. The steeper the delay discounting, the greater the subjective value of the gamble (over normal ranges of discounting steepness). Frequent gamblers, who value gambles highly, would thus be expected to discount delayed rewards more steeply than would nongamblers.

Response bouts are clusters of responses that occur in rapid succession and are punctuated by pauses during which the response does not occur. Under variable interval schedules of reinforcement, the number of responses in each bout (the bout length) varies among bouts. This experiment was aimed at determining whether the relative rate of reinforcement influenced the relative frequency of bouts of different lengths. Lever pressing in rats was reinforced under a tandem variable time (VT) 150‐s fixed ratio (FR) X, where X could be 1 or 5 and varied randomly after each reinforcer. Two conditions were included: majority FR1 (mFR1) and majority FR5 (mFR5). In mFR1, 75% of reinforcers had a tandem FR requirement of 1 and 25% had a tandem FR requirement of 5; this distribution was reversed in mFR5. The dynamic bi‐exponential refractory model of response bouts was fitted to the interresponse times (IRTs) in each condition. Model parameter estimates and IRTs were then used to simulate probable distributions of bout lengths. These distributions comprised a mixture of short geometrically‐distributed bout lengths and long negative‐binomially‐distributed bout lengths. Long bouts were significantly longer in the mFR5 condition than in the mFR1 condition. In conjunction with previous data, the present study suggests that the prevalence of long bouts increases with the proportion of reinforcers with FR5 requirement. These results suggest that bouts of different lengths are sensitive to the rate at which they are reinforced.

Delay and uncertainty of receipt both reduce the subjective value of reinforcers. Delay has a greater impact on the subjective value of smaller reinforcers than of larger ones while the reverse is true for uncertainty. We investigated the effect of reinforcer magnitude on discounting of delayed and uncertain reinforcers using a novel approach: embedding relevant choices within a computer game. Participants made repeated choices between smaller, certain, immediate outcomes and larger, but delayed or uncertain outcomes while experiencing the result of each choice. Participants' choices were generally well described by the hyperbolic discounting function. Smaller numbers of points were discounted more steeply than larger numbers as a function of delay but not probability. The novel experiential choice task described is a promising approach to investigating both delay and probability discounting in humans.

To understand how effort, defined by number of responses required to obtain a reward, affects reward value, five pigeons were exposed to a self‐control task. They chose between two alternatives, 2 s of access to food after a delay of 10 s, and 6 s of access to food after an adjusting delay. The adjusting delay increased or decreased depending on the pigeons' choices. The delay at which the two alternatives were equally chosen defined the indifference point. To determine whether requiring responses during the delay led to more impulsive (smaller–sooner rewards) or self‐controlled (larger–later rewards) choices, we varied the number of required pecks during the 10‐s delay to the 2‐s reinforcer, and assessed how the requirement affected the indifference points. In the High Rate Phase, they had to peck at least 10 times during the delay; in the Low Rate Phase, they could peck at most 5 times during the delay. For four pigeons the indifference point increased with the response requirement; for one pigeon it decreased. The results suggest that, in general, reward value varies inversely with effort.

Studies indicate that when abstinence is initiated, escalating reinforcement schedules maintain continuous abstinence longer than fixed reinforcement schedules. However, these studies were conducted for shorter durations than most clinical trials and also resulted in larger reinforcer value for escalating participants during the 1st week of the experiment. We tested whether escalating reinforcement schedules maintained abstinence longer than fixed reinforcement schedules in a 12‐week clinical trial. Smokers (146) were randomized to an escalating reinforcement schedule, a fixed reinforcement schedule, or a control condition. Escalating reinforcement participants received $5.00 for their first breath carbon monoxide (CO) sample <3 ppm, with a $0.50 increase for each consecutive sample. Fixed reinforcement participants received $19.75 for each breath CO sample <3 ppm. Control participants received payments only for delivering a breath CO sample. Similar proportions of escalating and fixed reinforcement participants met the breath CO criterion at least once. Escalating reinforcement participants maintained criterion breath CO levels longer than fixed reinforcement and control participants. Similar to previous short‐term studies, escalating reinforcement schedules maintained longer durations of abstinence than fixed reinforcement schedules during a clinical trial.

The purpose of the current study was to assess whether the establishment of listener relations with compound stimuli as samples and comparisons would lead to the emergence of: (1) speaker behavior in the form of tacts of the compound stimuli; (2) listener and tact responses for untaught compounds; and (3) listener and tact responses for the isolated properties of compounds. Participants were four boys diagnosed with autism and one diagnosed with intellectual disability. We taught participants to select among three compound comparisons consisting of combinations of shapes and patterns in the presence of the corresponding dictated word. Subsequently, we tested for the emergence of tacts for the trained compounds, as well as tact and listener relations for six untaught compounds and their properties. In general, results showed that the acquisition of listener relations led to the emergence of the corresponding tacts, as well as the emergence of listener and tact responses for untaught combinations for three out of five participants. By contrast, the other two participants showed responding characteristic of restricted stimulus control. These results suggest that the establishment of bidirectional relations between listener and speaker behaviors may facilitate the emergence of control by properties of compound stimuli.

We examined the effects of reinforcement magnitude on skill acquisition during discrete‐trial training. After conducting a magnitude preference assessment, we compared acquisition during conditions with large and small magnitudes of edible reinforcement to a praise‐only condition. Although all participants showed a preference for the large‐magnitude reinforcer, preference did not predict the magnitude that produced the fastest skill acquisition.

This study assessed whether tact training would establish analogies as measured by equivalence–equivalence relations. In Experiment 1, six college students were trained to tact “same” or “different” in the presence of AB and BC compounds based on component class membership (e.g., A1B1 as “same”, and A1B2 as “different”), and then tested on emergent tacts (BA, CB, AC, CA) and equivalence–equivalence relations. Only one of six participants passed all tests without remedial training. In Experiment 2, six college students were trained to tact only compounds belonging to the same class as “same”. Three of six participants passed all tests without remedial training. In Experiment 3, six college students were trained to tact stimuli belonging to the same class with a common name prior to exposure to relational tact training. All participants passed tests without remedial training. In Experiment 4, eight college students were trained to tact stimuli belonging to the same class with a common name. Six participants passed without remedial training, while two, who did not tact the relation of the compounds, did not. Results from these studies suggest that simple discrimination of individual components and their relation in the form of tacts is related with equivalence performance.

We examined the effects of the framing of time on delay discounting. Delay discounting is the process by which delayed outcomes are devalued as a function of time. Time in a titrating delay discounting task is often framed in calendar units (e.g., as 1 week, 1 month, etc.). When time is framed as a specific date, delayed outcomes are discounted less compared to the calendar format. Other forms of framing time; however, have not been explored. All participants completed a titrating calendar unit delay‐discounting task for money. Participants were also assigned to one of two delay discounting tasks: time as dates (e.g., June 1 st , 2015) or time in units of days (e.g., 5000 days), using the same delay distribution as the calendar delay‐discounting task. Time framed as dates resulted in less discounting compared to the calendar method, whereas time framed as days resulted in greater discounting compared to the calendar method. The hyperboloid model fit best compared to the hyperbola and exponential models. How time is framed may alter how participants attend to the delays as well as how the delayed outcome is valued. Altering how time is framed may serve to improve adherence to goals with delayed outcomes.