only marginally significantp < 0.001
We also performed a logistic regression on the first squeeze of each sequence for each individual monkey, and both effects were also significant at the subject level except for the reward size effect on monkey D which was only marginally significant (monkey A: β (sequence length) = − 0.82 ± 0.05, t (2740) = −15.83, p < 0.001, β (reward size) = 0.89 ± 0.05, t (2740) = 13.09, p < 0.001; monkey D: β (sequence length) = − 0.12 ± 0.05, t (1553) = − 2.41, p = 0.02, β (reward size) = − 0.09 ± 0.05, t (1553) = − 1.83, p = 0.07; monkey E: β (sequence length) = − 1.21 ± 0.10, t (1491) = − 11.78, p < 0.001, β (reward size) = 0.83 ± 0.07, t (1491) = 12.66, p < 0.001).