TY - JOUR
T1 - Do humans produce the speed-accuracy trade-off that maximizes reward rate?
AU - Bogacz, Rafal
AU - Hu, Peter T.
AU - Holmes, Philip J.
AU - Cohen, Jonathan D.
N1 - Funding Information:
Correspondence should be addressed to Rafal Bogacz, Department of Computer Science, University of Bristol, Bristol, BS8 1UB, UK. E-mail: [email protected] This work was supported by Engineering and Physical Sciences Research Council (EPSRC) Grant EP/C514416/1 and Public Health Service grants MH58480 and MH62196 (Cognitive and Neural Mechanisms of Conflict and Control, Silvio M. Conte Center). We thank Joshua Gold for providing us with the program to generate the “moving dots” stimuli, and for discussions, Patrick Simen for reading the manuscript and very useful comments, Eric Shea-Brown and Jeff Moehlis for advice on the planning and analysis of the experimental data, and Miriam Zackenhouse, Yakov Ben-Haim, and Paul Howard-Jones for discussion.
PY - 2010/5
Y1 - 2010/5
N2 - In this paper we investigate trade-offs between speed and accuracy that are produced by humans when confronted with a sequence of choices between two alternatives. We assume that the choice process is described by the drift diffusion model, in which the speed-accuracy trade-off is primarily controlled by the value of the decision threshold. We test the hypothesis that participants choose the decision threshold that maximizes reward rate, defined as an average number of rewards per unit of time. In particular, we test four predictions derived on the basis of this hypothesis in two behavioural experiments. The data from all participants of our experiments provide support only for some of the predictions, and on average the participants are slower and more accurate than predicted by reward rate maximization. However, when we limit our analysis to subgroups of 30-50% of participants who earned the highest overall rewards, all the predictions are satisfied by the data. This suggests that a substantial subset of participants do select decision thresholds that maximize reward rate. We also discuss possible reasons why the remaining participants select thresholds higher than optimal, including the possibility that participants optimize a combination of reward rate and accuracy or that they compensate for the influence of timing uncertainty, or both.
AB - In this paper we investigate trade-offs between speed and accuracy that are produced by humans when confronted with a sequence of choices between two alternatives. We assume that the choice process is described by the drift diffusion model, in which the speed-accuracy trade-off is primarily controlled by the value of the decision threshold. We test the hypothesis that participants choose the decision threshold that maximizes reward rate, defined as an average number of rewards per unit of time. In particular, we test four predictions derived on the basis of this hypothesis in two behavioural experiments. The data from all participants of our experiments provide support only for some of the predictions, and on average the participants are slower and more accurate than predicted by reward rate maximization. However, when we limit our analysis to subgroups of 30-50% of participants who earned the highest overall rewards, all the predictions are satisfied by the data. This suggests that a substantial subset of participants do select decision thresholds that maximize reward rate. We also discuss possible reasons why the remaining participants select thresholds higher than optimal, including the possibility that participants optimize a combination of reward rate and accuracy or that they compensate for the influence of timing uncertainty, or both.
KW - Drift diffusion model
KW - Reward rate
KW - Speed-accuracy trade-off
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U2 - 10.1080/17470210903091643
DO - 10.1080/17470210903091643
M3 - Article
C2 - 19746300
AN - SCOPUS:77951713282
SN - 1747-0218
VL - 63
SP - 863
EP - 891
JO - Quarterly Journal of Experimental Psychology
JF - Quarterly Journal of Experimental Psychology
IS - 5
ER -