Effects of varying length of stimulus series and response scale upon response latency,response uncertainty,and transmitted information

A 3 by 3 orthogonal design was employed t o study the interrelations among response latency (RL), response uncertainty (E_R), and transmitted information Nine groups of Ss judged the size of 5, 20, or 40 projected squares in terms of 5, 20, or 40 response categories. Patterns of change in ER and RL over the three stimulus series were differentially effected by increases in the number of available response categories. The increase from 5 to 20 response categories produced, for successively longer stimulus series, a constantly increasing change in E_R; the further increase from 20 to 40 categories produced a contrasting, constantly decreasing change in E_R. The same two changes in number of response categories produced the same pattern of change in RL over the 5- and 20-stimulus series but reversed the pattern for the 40-stimulus series. Correlations between E_R and RL ranged from .28 to .99 and tended to maximize when number of response categories equaled the number of stimuli. I_t was relatively low under all conditions. Within the 5- and 20-stimulus series, increases from 5 to 20 to 40 available responses increased RL in a negatively accelerated fashion but did not increase I_t. Within the 40-stimulus series, the same increases in number of available responses produced an essentially linear increase in both I_t and RL.