Figure 1.
Hypothetical sets of exponential curves for modeling speed—accuracy tradeoff across two groups of subjects. Young adults (solid lines) always show better performance than older adults (dotted lines). A: Young adults have a lower x-intercept than older adults; asymptote and rate are the same across groups. B: Young adults have a higher asymptote than older adults; x-intercept and rate are the same across groups. C: Young adults have a higher rate than older adults; x-intercept and asymptote are the same across groups. D: Young adults have a lower x-intercept, higher asymptote, and higher rate than older adults. dL = discriminability measure.