PercePtudl and Motor Skills, 1977,45, 1216-1218.
@ Perceptual and Motor Skills 1977
LEFT-HANDEDNESS AMONG ARCHITECTS: PARTIAL REPLICATION AND SOME NEW DATA JOHN M. PETERSON AND LEONARD M. LANSKY University of Cincinndti Summary.-As predicted, over a 6-yr. period, more left-handed proportionately than right-handed architecture smdents successfully completed their 6-yr. program. Contrary to expectation, the entering class in 1976 had 21 % lefthanded males, 12 of 57. Lastly these left-handed men hnpd high factor scores in a group of academic predictors, design scores, and grade point averages during the first quarter. The 45 right-handed men in the entering class had almost zero mean scores on ;he predictors and negative mean scores on performance. The 19 right-handed women in the class had negative scorer on the academic predictors and positive ones on performance.
In 1974 we published data on architecture students and faculty (Peterson & Lansky, 1974) . Ten percent of 1970's entering class were left-handed, within chance expecration. However, some subsequent classes had more left-handed students. In addition 29% of the faculty were left-handed. The present paper explores several questions: ( 1 ) What percent of the graduating classes since 1970 were left-handed? ( 2 ) What percent of the 1976 entering class were left-handed? ( 3 ) For the entering class do a number of variables related to academic performance and design distinguish right- and left-handed males and either group from right-handed women (there were no left-handed women in the entering class) ? 5
The subjects for the first question were the 484 smdents who were enrolled in architecture at the University of Cincinnati between the fall of 1970 and the summer of 1976. For the other questions, the subjects were the 76 students who entered the program in the fall of 1976, 19 right-handed women, 12 left-handed men, and 45 right-handed men. For those persons tested prior to 1976, handedness was assessed on a fivepoint self-report scale with three anchoring points: "I am totally right-handed," "I use either hand equally," and "I am totally left-handed." Since 1976, we have used Oldfield's scale which consists of 10 actions for which individuals report the preferred hand (Oldfield, 1971). A handedness quotient is computed; negative scorers are "left-handed." For the 197G freshman class, we had 11 measures: four on academic predictors (including the Scholastic Aptitude Test), the handedness score mentioned above, four measures derived from the students' line drawings of a cube, their first-quarter grade in design, and grade point average. The scores on the
LEFT-HANDEDNESS AMONG ARCHITECTS
1217
line drawings referred to the angles with which students drew on the page and the degree of slant in the lines of the cube which were used to represent depth. The handedness quotient and the drawings of the cube were obtained during the first design classes. These 11 scores were correlated with one another for the 76 entering stux and factor dents. The matrix was factor analyzed using an ~ ~ u a m arotation, scores were obtained on the resulting factors. Pairs of the resultant arrays for the three groups were compared on each factor by t tests.
RESULTS AND DISCUSSION As predicted, between 1970 and 1976, proportionally more left-handed students than right-handed students graduated from the program. Of 405 right-handed students, 25 1 (62 % ) graduated; of 79 left-handed students, 58 (73.4% ) graduated. The Likelihood Ratio of 3.75 was significant at the .05 level. For the entering class in 1976, 12 (21%) of the 57 men were left-handed (16% of the total sample of 76). The former figure is more than twice the number which would be expected by chance, taking chance as 10%. W e still lack any theory to account for these two findings. The second is most surprising in light of the data reported earlier. As of this writing we do not know if the word is out concerning the potential for success in architecture at the University of Cincinnati for left-handed students ( 'Vasari,' 1977) . Nor do we know if the higher percentage of left-handers in the entering class reflects a change in demands on children to shift hands, thus producing more left-handers than our assumed 10%. Lastly it is possible that the Oldfield scale picks up more "left-handers" than our five-point scale did. The data on the factor analysis give an interesting picture. For the matrix of 11 variables on the 76 entering students, four factors were extracted. They accounted for 68% of the variance (29, 16, 12, and 11% respectively). The first, labelled F1-Academic Predictors, had high loadings on four variables: Verbal SAT ( -.66), Mathematics SAT ( -.85 ) , High School Rank ( -.73 ) , and Predicted Grade Point Average ( -.96). The second factor, F2-Cube/ Handedness, had high loadings on the handedness quotient (-.62) and the four measures of the drawings of the cube (.75, .77, .37, and -35 respectively). The third factor, F3-Academic Performance, had high loadings on the two remaining measures, the first quarter's design grade (-90) and grade point average ( -.71). The fourth factor had high loadings on two of the measures on the drawing of the cube (.76 and .76 respectively). A larger sample would have been useful. However, the study is exploratory, and the number of architecture students for whom there are relevant data is limited. The three groups were compared on their mean factor scores. As might be
12 18
J. M. PETERSON & L. M. LANSKY
expected, on Factor l-Academic Predictors, the mean of left-handed men was higher than that for right-handed men which in turn was higher than that for the women: the latter had negative mean scores. The comparison of lefthanders with the women was significant beyond the .05 level for the one-tailed test, the comparison between the men at the .10 level. On Factor 2, Handedness, as might be expkted, left-handed males had higher means than either .001). Again the women had negative mean scores right-hand group ( p for the factor. Lastly on Factor 3-Academic Performance, as might have been predicted, the left-handed men had higher mean scores than either other group but just barely larger than the right-handed women. The right-handed men had negative mean scores which were significantly lower (p < .01) than those for the right-handed women. The combinations of facror scores for the right-handed men and women are interesting. While the men have almost zero mean on academic predictors, they have a negative mean on perlormance; the pattern is different for the women: they have a negative mean on predictors but positive ones on performance, almost equalling those of the left-handed men. For the right-handed men we are attempting some detailed analyses to compare those with positive and those with negative scores on academic predictors and performance. For the women the data have other implications. Perhaps we have data on sexism in selection-the predictors are negative for the same women who perform positively. However, the grades for the women, all of whom are right-handed, may reflect morivation more than "natural ability," whatever that might mean. W e intend to look at the details of the performance by the right-handed women for clues that might help us to identify their counterparts among the right-handed men, i.e., those men who do well. Lastly we have verified that there is consistenCy in the performance of left-handed men; they score positively on predictors and on performance. However, we are still a long way from explaining the phenomena.
@ Perceptual and Motor Skills 1977
LEFT-HANDEDNESS AMONG ARCHITECTS: PARTIAL REPLICATION AND SOME NEW DATA JOHN M. PETERSON AND LEONARD M. LANSKY University of Cincinndti Summary.-As predicted, over a 6-yr. period, more left-handed proportionately than right-handed architecture smdents successfully completed their 6-yr. program. Contrary to expectation, the entering class in 1976 had 21 % lefthanded males, 12 of 57. Lastly these left-handed men hnpd high factor scores in a group of academic predictors, design scores, and grade point averages during the first quarter. The 45 right-handed men in the entering class had almost zero mean scores on ;he predictors and negative mean scores on performance. The 19 right-handed women in the class had negative scorer on the academic predictors and positive ones on performance.
In 1974 we published data on architecture students and faculty (Peterson & Lansky, 1974) . Ten percent of 1970's entering class were left-handed, within chance expecration. However, some subsequent classes had more left-handed students. In addition 29% of the faculty were left-handed. The present paper explores several questions: ( 1 ) What percent of the graduating classes since 1970 were left-handed? ( 2 ) What percent of the 1976 entering class were left-handed? ( 3 ) For the entering class do a number of variables related to academic performance and design distinguish right- and left-handed males and either group from right-handed women (there were no left-handed women in the entering class) ? 5
The subjects for the first question were the 484 smdents who were enrolled in architecture at the University of Cincinnati between the fall of 1970 and the summer of 1976. For the other questions, the subjects were the 76 students who entered the program in the fall of 1976, 19 right-handed women, 12 left-handed men, and 45 right-handed men. For those persons tested prior to 1976, handedness was assessed on a fivepoint self-report scale with three anchoring points: "I am totally right-handed," "I use either hand equally," and "I am totally left-handed." Since 1976, we have used Oldfield's scale which consists of 10 actions for which individuals report the preferred hand (Oldfield, 1971). A handedness quotient is computed; negative scorers are "left-handed." For the 197G freshman class, we had 11 measures: four on academic predictors (including the Scholastic Aptitude Test), the handedness score mentioned above, four measures derived from the students' line drawings of a cube, their first-quarter grade in design, and grade point average. The scores on the
LEFT-HANDEDNESS AMONG ARCHITECTS
1217
line drawings referred to the angles with which students drew on the page and the degree of slant in the lines of the cube which were used to represent depth. The handedness quotient and the drawings of the cube were obtained during the first design classes. These 11 scores were correlated with one another for the 76 entering stux and factor dents. The matrix was factor analyzed using an ~ ~ u a m arotation, scores were obtained on the resulting factors. Pairs of the resultant arrays for the three groups were compared on each factor by t tests.
RESULTS AND DISCUSSION As predicted, between 1970 and 1976, proportionally more left-handed students than right-handed students graduated from the program. Of 405 right-handed students, 25 1 (62 % ) graduated; of 79 left-handed students, 58 (73.4% ) graduated. The Likelihood Ratio of 3.75 was significant at the .05 level. For the entering class in 1976, 12 (21%) of the 57 men were left-handed (16% of the total sample of 76). The former figure is more than twice the number which would be expected by chance, taking chance as 10%. W e still lack any theory to account for these two findings. The second is most surprising in light of the data reported earlier. As of this writing we do not know if the word is out concerning the potential for success in architecture at the University of Cincinnati for left-handed students ( 'Vasari,' 1977) . Nor do we know if the higher percentage of left-handers in the entering class reflects a change in demands on children to shift hands, thus producing more left-handers than our assumed 10%. Lastly it is possible that the Oldfield scale picks up more "left-handers" than our five-point scale did. The data on the factor analysis give an interesting picture. For the matrix of 11 variables on the 76 entering students, four factors were extracted. They accounted for 68% of the variance (29, 16, 12, and 11% respectively). The first, labelled F1-Academic Predictors, had high loadings on four variables: Verbal SAT ( -.66), Mathematics SAT ( -.85 ) , High School Rank ( -.73 ) , and Predicted Grade Point Average ( -.96). The second factor, F2-Cube/ Handedness, had high loadings on the handedness quotient (-.62) and the four measures of the drawings of the cube (.75, .77, .37, and -35 respectively). The third factor, F3-Academic Performance, had high loadings on the two remaining measures, the first quarter's design grade (-90) and grade point average ( -.71). The fourth factor had high loadings on two of the measures on the drawing of the cube (.76 and .76 respectively). A larger sample would have been useful. However, the study is exploratory, and the number of architecture students for whom there are relevant data is limited. The three groups were compared on their mean factor scores. As might be
12 18
J. M. PETERSON & L. M. LANSKY
expected, on Factor l-Academic Predictors, the mean of left-handed men was higher than that for right-handed men which in turn was higher than that for the women: the latter had negative mean scores. The comparison of lefthanders with the women was significant beyond the .05 level for the one-tailed test, the comparison between the men at the .10 level. On Factor 2, Handedness, as might be expkted, left-handed males had higher means than either .001). Again the women had negative mean scores right-hand group ( p for the factor. Lastly on Factor 3-Academic Performance, as might have been predicted, the left-handed men had higher mean scores than either other group but just barely larger than the right-handed women. The right-handed men had negative mean scores which were significantly lower (p < .01) than those for the right-handed women. The combinations of facror scores for the right-handed men and women are interesting. While the men have almost zero mean on academic predictors, they have a negative mean on perlormance; the pattern is different for the women: they have a negative mean on predictors but positive ones on performance, almost equalling those of the left-handed men. For the right-handed men we are attempting some detailed analyses to compare those with positive and those with negative scores on academic predictors and performance. For the women the data have other implications. Perhaps we have data on sexism in selection-the predictors are negative for the same women who perform positively. However, the grades for the women, all of whom are right-handed, may reflect morivation more than "natural ability," whatever that might mean. W e intend to look at the details of the performance by the right-handed women for clues that might help us to identify their counterparts among the right-handed men, i.e., those men who do well. Lastly we have verified that there is consistenCy in the performance of left-handed men; they score positively on predictors and on performance. However, we are still a long way from explaining the phenomena.
