Letter Similarity Data Set Archive

Geyer, 1977

Geyer, L. H. (1977). Recognition and confusion of the lowercase alphabet. Perception & Psychophysics, 22, 487-490.



Experimenter provides a confusion matrix for the lowercase English alphabet.


Letters were the Tactype Futura demi 5424 font face, with tall letters subtending .2 degrees visual angle. Brightness and duration were adjusted to achieve 50% correct recall. A scanned reproduction of these letters from the original article is shown below.

Click to enlarge


The confusion matrix are available here. For this matrix, each row represents a presented stimulus, and each column a response. Results are based on seven paid volunteers, who each performed 650 trials across two sessions (with two other preparatory sessions.)

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