These results provide additional support for the decision model as an account of choice in concurrent chains.
Following treatment evaluation, a concurrent chain was conducted to evaluate participant preference for redirection or response blocking.
Concurrent chains is widely used to study pigeons' choice between terminal links that can vary in delay, magnitude, or probability of reinforcement.
Grace and McLean's [Grace, R.C., McLean, A., 2006. Rapid acquisition in concurrent chains: evidence for a decision model. J. Exp. Anal. Behav. 85, 181 202] decision model provided a good description of the data and predicted the terminal-link effect.
We review the long history of research on operant choice: the matching law, its extensions and problems, concurrent chain schedules and self control.
Bayesian inferences were performed with PhyloBayes 3.2 [35] under the CAT+ Γ4 model of amino acid substitution running two concurrent chains terminated using PhyloBayes automatic stopping rule (maxdiff <0.3).
We used Markov chain settings of one long chain with 5000 recorded steps (long-sample), 10 concurrent chains (replicates), and 15 000 discarded trees per chain (burn-in).
Four concurrent chains were implemented during each run, with each chain using a static heating scheme based on temperature values of 1.0, 1.5, 3.0, and 10.
For all the analyses we used an adaptive heating scheme with 4 concurrent chains; the analyses were run on a cluster computer using up to 80 compute nodes.
Bayesian phylogenetic analyses were performed using MRBAYES version 3.1.2 (Huelsenbeck and Ronquist 2001), where four concurrent chains were run for 6 × 10 generations.
Two completely independent runs using starting UPGMA trees were performed, with each run based on 20 concurrent chains with 1000 recording steps made at 100 step intervals.
