Letter Similarity Data Set Archive |
References for complete list are available here.
A paper based on some of this work is published in Acta Psychologica. Mueller, S. T. & Weidemann, C. T. (2012). Alphabetic Letter Identification: Effects of perceivability, similarity, and bias. Acta Psychologica, 139, 19-37. http://dx.doi.org/10.1016/j.actpsy.2011.09.014
Reference | Method | Case | Typeface |
Cattell, 1886 | Naming errors | B | Latin serif |
Naming errors | B | Fraktur | |
Sanford, 1888 | Naming errors of distant stimuli | L | Snellen |
Naming errors of brief stimuli | L | Snellen | |
Naming errors of brief stimuli | L | Old-style Snellen | |
Dockeray, 1910 | Naming errors of stimuli in periphery | L | 10-pt. Roman old-style |
Roethlein, 1912 | Confusable letter sets | B | 16 different fonts |
Hartridge, 1922 | Naming of distant stimuli | U | Green's Letter Set |
Korte, 1923 | Naming of distant stimuli | B | Antiqua |
Naming of distant stimuli | B | Fraktur | |
Banister, 1927 | Naming of distant brief stimuli | U | Green's Letter Set |
Naming of distant brief stimuli | U | Green's Letter Set | |
Naming of distant stimuli | U | Green's Letter Set | |
Tinker, 1928 | Naming of brief stimuli | B | Bold serif font |
Ovink, 1938 | Naming of distant stimuli | B | 11 different fonts |
Hodge, 1962 | Letter reading errors | B | Uniform-stroke alphabet |
Gibson et al, 1963 | Children's matching of target to set of random choices | U | Sign-typewriter |
Children's matching of target to set of similar or dissimilar letters | U | Sign-typewriter | |
Popp, 1964 | Forced choice confusions of children | L | Century-style |
Bell, 1967 | Naming errors of brief stimuli | U | Long Gothic |
Naming errors of brief stimuli | L | Murray | |
Dunn-Rankin, 1968 | Similarity preference of letter pairs | L | Century Schoolbook |
Dunn-Rankin et al, 1968 | *Shape congruency | L | Century Schoolbook |
Kuennapas, 1969 | Subjective similarity ratings | L | Sans serif Swedish alphabet |
Uttal, 1969 | Naming errors of brief masked stimuli | U | 5x7 dot matrix |
Laughery, 1969 | *Feature Analysis | U | Roman block letters |
Gibson, 1969 | *Feature Analysis | U | Roman block letters |
Fisher, et al., 1969 | Naming errors of 200-ms stimuli | U | Futura medium |
Naming errors of 400-ms stimuli | U | Futura medium | |
Naming errors of brief stimuli | U | Leroy lettering set | |
Townsend, 1971a | Naming errors of brief unmasked stimuli | U | Typewriter font |
Naming errors of brief masked stimuli | U | Typewriter font | |
Townsend, 1971b | Naming errors of brief unmasked stimuli | U | Typewriter font |
Bouma, 1971 | Naming errors of distant stimuli | L | Courier |
Naming errors of stimuli in periphery | L | Courier | |
Geyer, 1973 | *Feature analysis | U | Roman block letters |
Engel, et al., 1973 | Naming errors of brief stimuli | L | Century Schoolbook |
Loomis, 1974 | Tactile letter identification | U | 18x13 matrix |
Briggs, 1975 | *Feature analysis | U | Roman block letters |
Mayzner, 1975 | Naming errors of brief stimuli | U | 5x7 dot matrix |
Thorson, 1976 | *Overlap values based on feature analysis | U | Roman block letters |
Geyer, 1977 | Naming errors of brief dim stimuli | L | Tactype Futura demi 5452 |
Coffin, 1978 | *Fourier spectra similarity | U | 128x128-pixel block letters |
Podgorny and Garner, 1979 | Same-different choice RT | U | 5x7 Dot matrix chars. |
Subjective similarity ratings | U | 5x7 Dot matrix chars. | |
Gilmore, et al., 1979 | Naming errors of brief stimuli | U | 5x7 Dot matrix chars. |
Kikuchu, et al., 1979 | Tactile letter identification | U | 17x17 Dot matrix chars. |
Craig, 1979 | Tactile letter identification | U | 6x18 Dot matrix chars. |
Keren and Beggen, 1981 | *Feature analysis | U | 5x7 Dot matrix chars. |
Johnson & Phillips, 1981 | Tactile letter identification | U | Sans serif embossed letters |
Geyer & Gupta, 1981 | Naming Confusions for nine letters | U | Three fonts (dots, filled, stroked) |
Loomis, 1982 | Visual identification | U | Blurred Helvetica |
Tactual identification | U | Helvetica | |
Paap, et al., 1982 | Naming errors | U | Terak |
Gupta, et al., 1983 | Naming errors of brief dim stimuli | U | 5x7 Dot matrix chars. |
Naming errors of brief dim stimuli | U | Keepsake | |
Phillips, et al., 1983 | Naming errors of small visual stimuli | U | Helvetica |
Tactile identification | U | Sans serif | |
Gervais, et al., 1984 | Naming errors of brief stimuli | U | Helvetica |
*Similarity of spatial frequency spectra | U | Helvetica | |
VanNes, et al., 1983 | Naming errors of brief peripheral stimuli | L | 12x10 pixel matrix-least confusable (IPO-Normal) |
Naming errors of brief peripheral stimuli | L | 12x10 pixel matrix-most confusable | |
VanderHeijden, et al., 1984 | Naming errors of brief stimuli | U | Sans serif roman |
Blough, 1985 | Pigeon's 2-alternative letter matching | U | 5x7 dot matrix |
Blommaert, 1988 | *Fourier spectra similarity | L | 16x32 pixel matrix courier |
Heiser, 1988 | *Choice model analysis of confusions | U | Sans serif roman |
Jacobs, et al., 1989 | Saccade times to matching target | L | 9x10 pixel matrix |
Saccade errors to distractor | L | 9x10 pixel matrix | |
Boles and Clifford, 1989 | Subjective similarity ratings | B | Apple-Psych letters |
Courrieu & de Falco, 1989 | Children identifying targets that matched uppercase reference | L | Printed script |
Watson, 1989 | Naming errors of low-contrast stimuli | U | 5x9 pixel font (gacha.r.7) |
McGraw, et al., 1994 | Letter identification with keyboard | L | ``Gridfont'' chars. |
Reich & Bedell, 2000 | Naming of tiny or peripheral letters | U | Sloan Letters |
Liu & Arditi, 2001 | Naming of tiny crowded or spaced letter strings | U | Sloan Letters |
Mueller and Weidemann (2012) | Forced choice identification of letter with distractor: @-mask | U | Courier |
Forced choice response latencies: @-mask | U | Courier | |
Forced choice identification of letter with distractor: #-mask | U | Courier | |
Forced choice response latencies: #-mask | U | Courier | |
Simpson et al., 2012 | Subjective similarity ratings | B | |
Note. In the Case column, ``L'' indicates lowercase, ``U'' indicates uppercase, and ``B'' indicates both cases were studied. Methods denoted with an * were measures developed by analyzing the visual form of letters, and not directly based on empirical data. |