Fig. 2.

First-stage choice behavior by age. The proportion of first-stage stay choices is graphed as a function of outcome of the previous trial for each age group (a), separately for trials following common and rare transitions. The error bars represent ±1 SEM. The scatterplot (with best-fitting regression line) shows the relationship between the reward-by-transition-type interaction effect (the model-based effect estimates) and age (b). The model-based effect is plotted as the fixed plus the random effects from a regression model with age excluded. The gray area represents ±1 SEM.