Article

The stay/switch model describes choice among magnitudes of reinforcers.

Department of Psychology, Fordham University, 441 East Fordham Road, Bronx, NY 10458, United States.
Behavioural Processes (Impact Factor: 1.46). 07/2008; 78(2):173-84. DOI: 10.1016/j.beproc.2008.03.002
Source: PubMed

ABSTRACT The stay/switch model is an alternative to the generalized matching law for describing choice in concurrent procedures. The purpose of the present experiment was to extend this model to choice among magnitudes of reinforcers. Rats were exposed to conditions in which the magnitude of reinforcers (number of food pellets) varied for staying at alternative 1, switching from alternative 1, staying at alternative 2 and switching from alternative 2. A changeover delay was not used. The results showed that the stay/switch model provided a good account of the data overall, and deviations from fits of the generalized matching law to response allocation data were in the direction predicted by the stay/switch model. In addition, comparisons among specific conditions suggested that varying the ratio of obtained reinforcers, as in the generalized matching law, was not necessary to change the response and time allocations. Other comparisons suggested that varying the ratio of obtained reinforcers was not sufficient to change response allocation. Taken together these results provide additional support for the stay/switch model of concurrent choice.

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    • "Even in these situations, a variety of animals choose larger amounts of foods when given choices between discrete sets of identical food items (e.g., Addessi, Crescimbene, & Visalberghi, 2008; Anderson, Awazu, & Fujita, 2000; Anderson et al., 2005; Beran, 2001; Call, 2000; Hanus & Call, 2007; Rumbaugh, Savage-Rumbaugh, & Hegel, 1987; Uller, Jaeger, Guidry, & Martin, 2003) and continuous quantities such as liquids (e.g., Suda & Call, 2005; vanMarle, Aw, McCrink, & Santos, 2006; Wood, Hauser, Glynn, & Barner, 2008). Extensive research has shown that magnitude of food reward guides choice behavior in a variety of contexts even when other variables such as delay length to reward and unpredictability of reward also are manipulated (e.g., Green, Myerson, Holt, Slevin, & Estle, 2004; Landon, Davidson, & Elliffe, 2003; MacDonall, 2008; Steinhauer, 1984; Young, 1981). "
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