Multidimensional Similarity of Letters

TLDR: ‘Vertical linearity’ and ‘Roundness’ are the most important of these factors and account for a considerable portion of the similarity among many letters.

Abstract: Summary.-28 lower-case letters of the Swedish alphabet were studied by the method of multidimensional similarity analysis. 57 Ss participated in the experiment. 9 factors were found. Factor I is called 't' or 'Vertical linearity,' Factor 11: '0' or 'Roundness,' Factor 111: 'n' or 'Parallel vertical linearity,' Factor IV: 'i' or 'Vertical linearity with dot,' Factor V: 'p' or 'Roundness attached to vertical linearity,' Factor VI: 'k' or 'Vertical linearity with crossness,' Factor VII: 'a' or 'Roundness attached to a hook,' Factor VIII: 'v' or 'Angularity open upward' and Factor IX: '2' or 'Zigzaggedness.' 'Vertical linearity' and 'Roundness' are the most important of these factors and account for a considerable portion of the similarity among many letters. In previous experiments with nine capital letters (Kuennapas, 1966, 1967, 1968a) it was shown that multidimensional similarity analysis (Ekman, 1965, 1968) could be used successfully for the study of the perceived forms of these capitals. The factors revealed by the analyses could be interpreted easily and meaningfully as 'Rectangularity,' 'Roundness' and 'Vertical linearity.' The purposes of the present study were (a) to extend the multidimensional similarity analysis to the whole alphabet of lower-case letters, and (b) to reveal the main perceptual dimensions of visual forms of these letters.