Title: Wheels Source: Broderson (1968) Description: Ten stimuli were constructed that looked like one-spoked wheels. These stimuli were circles varying in diameter from 12.5 mm to 32.5 mm; they also had a drawn-in radius line at angles varying from 21 to 69 degrees. Each of the 45 pairs of the one-spoked wheels 1, ..., 10 was drawn on a card and presented to subjects with the instruction to rate this pair's global similarity on a scale from '1= minimal similarity' to '7=maximal similarity'. This led to a 10 times 10 matrix of similarity scores for each subject. The table contains the mean scores for all 50 subjects are shown in .