Complexity ratings of digit strings and their pictorial analogs

Abstract

In each of three experiments, one group of Ss rated complexity of short strings of decimal digits and another group rated the complexity of the pictorial analogs of the digit strings. The pictorial analog of a digit string was the dot-line graph or bar graph representing the heights of the digits in the string. The physical properties of these two types of stimuli are quite different, but the mean complexity ratings for 2-, 5- and 8-place digits and their pictorial analogs had high positive correlations. This was interpreted as evidence that the underlying code for the two types of stimuli is similar. Some evidence for the effect of digit size and size of digit differences on complexity ratings was also found.