- Email: [email protected]
Use of Holland's vocational theory with potential high school dropouts
Journal of Vocational
Behavior
10, 35-38 (1977)
Use of Holland’s Vocational Theory Potential High School Dropouts
with
CLAUDE H. CUNNINGHAM,HERBERT L. ALSTON, EUGENE B. DOUGHTIE, AND JAMES A. WAKEFIELD,JR. Houston
Independent School District, Houston Independent School District University of Houston. University of Houston and California State College, Stanislaus
and
The construct validity for potential high school dropouts of Holland’s theory of vocational choice as measured by the Vocational Preference Inventory (VPI) was studied. The hexagonal arrangement proposed by Holland of the constructs in factor space for potential high school dropouts was supported using the modeltesting procedure of Wakefield and Doughtie (Juurnal of Counseling Psychology. 1973, 20, 513-518). The correspondence of the constructs measured by the VP1 for potential high school dropouts and college students was found to be substantially the same using the factor-relating procedure of Kaiser, Hunka, and Bianchini (In H. J. Eysenck & S. B. G. Eysenck (Eds.), Personality structure and measurement. San Diego, Calif.: Knapp, 1969, pp. 333-343). These results indicate that Holland’s theory is appropriate for potential high school dropouts and, by implication, for other high school students.
Holland (1973) has proposed a theory of vocational choice in terms of personality types which has received considerable support (e.g., Wakefield & Doughtie, 1973; Williams, 1972; Osipow, Ashby, & Wall, 1966). The Vocational Preference Inventory (VPI) (Holland, 1970) is the most frequently used instrument for measuring the constructs in Holland’s theory. The VP1 is a straightforward, nonthreatening instrument by which vocational interests may be indicated. The measure consists of 160 occupational titles. The testee is asked to indicate in which of the occupations listed he would like to be engaged and which he would not like. Wakefield and Doughtie (1973) have proposed a model-testing procedure to investigate the construct validity of Holland’s theory. This procedure examines the relationships among the constructs in factor space for correspondence with Holland’s hexagonal model of these relationships. The construct validity of Holland’s theory has been strongly supported for college populations using this procedure (Wakefield & Doughtie, 1973; Wakefield, Yom, Doughtie, Chang, & Alston, 1975). Kaiser, Hunka, and Bianchini (1969) have noted that the same instruments used with different populations may not measure the same variRequests for reprints should be sent to Dr. EugeneB. Doughtie, Departmentof psy&ology, University of Houston, 3801 Cullen Boulevard, Houston, TX 77004. 35 Copyright 0 1977 by Academtc Press. Inc All rights of reproducrmn m any form reserved.
ISSN 000-8791
36
CUNNINGHAM ETAL
ables and have presented a method of determining the degree of correspondence between the factor structures of different populations. Using the factor-relating procedure proposed by Kaiser et al. (1969), Alston, Wakefield, Doughtie, and Bobele (1976) reported that the constructs measured by the VP1 are substantially the same for male and female college students, and Yom, Doughtie, Chang, Alston, and Wakefield (1975) reported that the constructs measured by the VPI are very similar for black and white college students. The present study addresses the question of whether or not the VP1 can be used with potential high school dropouts. The subjects for this study were chosen because their academic orientation and educational background are the maximally different we can find from the college population previously studied (Alston et al., 1976). It is reasoned that if Holland’s theory holds for this extreme group then one might feel more sanguine in using Holland’s theory when counseling other high school students who are less dissimilar to the college group. In addition, many potential high school dropouts are encouraged to participate in vocationally oriented programs and because the validity of Holland’s theory with such a population has received little investigation. The fact that potential high school dropouts are less academically oriented raises the question of whether or not Holland’s theory of vocational interests, which has been supported for college students, is appropriate for counseling potential high school dropouts enrolled in vocational programs. Wakefield and Doughtie’s (1973) model-testing procedure was used to assess the relations among interest types to learn if they conform to the hypothesized geometric model. This is one of the many tests of construct validity needed to evaluate the usefulness of the theory and its classification scheme. The factor-relating procedure of Kaiser et al. (1969) was used to determine the degree of correspondence between the constructs measured by the VP1 for potential high school dropouts and college students. METHOD Subjects. The high school sample consisted of 252 students and constituted the total number of students enrolled in a special learning center for potential dropouts. One hundred forty-nine were males and 103 were females. The mean chronological age was 16.9 years, with a standard deviation of 1.36 years. The group contained Anglo-, Black, and Mexican Americans. The college sample with which the high school sample was compared was the sample reported by Alston et al. (1976) and consisted of 174 students, 82 males and 92 females. The sample was predominately Anglo-American, with a mean chronological age of 23.6 years and a standard deviation of 5.7.
VP1 WITH HIGH SCHOOL STUDENTS
37
Analysis. The Wakefield and Doughtie (1973) model-testing procedure was used to test Holland’s hexagonal model, This procedure requires computing the Pearson product-moment correlations between the constructs measured by the VPI, factor-analyzing the resulting correlation matrix by the principal components method (Harman, 1967), and computing the distances between each pair of constructs in the resulting factor space. After the distances between pairs of constructs are computed, these distances are compared with each other in relation to Holland’s model of construct relationships. Holland’s hexagonal model involves 54 independent distance comparisons between pairs of constructs. The normal approximation of the binomial sampling distribution requires that 34 of the 54 comparisons be in the predicted direction to reject the hypothesis of a random arrangement of the constructs in Holland’s model at the .05 level of significance. Thirtyseven of the 54 construct pair comparisons must be as predicted for significance at the .Ol level. The Kaiser et al. (1969) factor-relating procedure was used to measure the correspondence of the constructs measured by the VP1 for high school and college students. This procedure involved factor-analyzing the correlation matrix of VP1 constructs by the principal components procedure (Harman, 1967) separately for each group. The resulting factor matrices were then compared using the factor-relating procedure of Kaiser et al. This computation was accomplished using a computer program by Veldman (1967). The cosines obtained between the test vectors are interpreted as correlation coefficients and indicate the degree to which the VP1 scales measure the same constructs for both groups. The mean of these cosines indicates the extent to which the test as a whole measures the same constructs for both groups. RESULTS
AND DISCUSSION
Of the 54 distance comparisons between the constructs in Holland’s hexagonal model for high school students, 40 were consistent with Holland’s model of personality types. The z score corresponding to 40 correct observations is 3.402 (p < .OOl). These results support the arrangement of the constructs as shown in Holland’s model. The cosines of the 11 VP1 scales between the potential high school dropouts and college student groups can be seen in Table 1. The mean of the six constructs in Holland’s theory is .95. This is evidence that the VP1 measures largely the same constructs for both groups. The findings that Holland’s hexagonal model holds for potential high school dropouts and that the constructs measured by the VP1 are substantially the same for both potential high school dropouts and college students provide additional support for Holland’s theory. These findings also
38
CUNNINGHAM
ET AL.
TABLE I Cosines between Test Vectors for Potential High School Dropouts and College Students” Scale
Cosine
Realistic Intellectual Social Conventional Enterprising Artistic
.99 .95 .92 .89 .89 .94
Scale Self-control Masculinity Status Infrequency Acquisition
Cosine .96 .99 .98 .97 1.00
(I Cosines are rounded to two decimal places.
imply that Holland’s theory should apply to other high school students who are less dissimilar to the college comparison group than the potential high school dropouts. More important, the results support the use of the VP1 with these students to measure their vocational interests and suggest that the interpretation of VP1 profiles is the same for both potential high school dropouts and college students. REFERENCES Alston, H. L., Wakefield, J. A., Jr., Doughtie, E. B., & Bobele, R. M. Correspondence of constructs in Holland’s theory for male and female college students. Journal of Vocational Behavior,
1976, 8, 85-88.
Harman, H. H. Modern factor analysis. Chicago: University of Chicago Press, 1967. Holland, J. L. Making vocational choices: A theory of careers. Englewood Cliffs, N. J.: PrenticeHall, 1973. Holland, J. L. Manualfor the Vocational Preference Inventogl. Palo Alto, Calif.: Consulting Psychologists Press, 1970. Kaiser, H. F., Hunka, S., & Bianchini, J. Relating factors between studies based upon different individuals. In H. J. Eysenck & S. B. G. Eysenck (Eds.), Personality structure and measurement. San Diego, Calif.: Knapp, 1969, pp. 333-343. Osipow, S. H., Ashby, J. D., & Wall, H. W. Personality types and vocational choice: A test of Holland’s theory. Personnel and Guidance Journal, 1966, 45, 37-42. Veldman, D. J. Fortran programming for rhe behatpiora/ sciences. New York: Holt, Rinehart & Winston, 1967. Wakefield, J. A., Jr., & Doughtie, E. B. The geometric relationship between Holland’s personality typology and the Vocational Preference Inventory. Journal of Counseling Psychology,
1973, 20, 513-518.
Wakefield, J. A., Jr., Yom, B. L., Doughtie, E. B., Chang, W. C., & Alston, H. L. The geometric relationship between Holland’s personality typology and the Vocational Preference Inventory for blacks. Journal of Counseling Psychology, 1975. 22, 58-60. Williams, C. M. Occupational choice of male graduate students as related to values and personality: A test of Holland’s theory. Journal of Vocational Behavior, 1972,2,39-46. Yom, B. L., Doughtie, E. B., Chang, W. C., Alston, H. L., & Wakefield, J. A., Jr. The factor structure of the Vocational Preference Inventory for black and white college students. Journal of Vocational Behavior, 1975, 6, 15-18. Received: March 8, 1976.
Behavior
10, 35-38 (1977)
Use of Holland’s Vocational Theory Potential High School Dropouts
with
CLAUDE H. CUNNINGHAM,HERBERT L. ALSTON, EUGENE B. DOUGHTIE, AND JAMES A. WAKEFIELD,JR. Houston
Independent School District, Houston Independent School District University of Houston. University of Houston and California State College, Stanislaus
and
The construct validity for potential high school dropouts of Holland’s theory of vocational choice as measured by the Vocational Preference Inventory (VPI) was studied. The hexagonal arrangement proposed by Holland of the constructs in factor space for potential high school dropouts was supported using the modeltesting procedure of Wakefield and Doughtie (Juurnal of Counseling Psychology. 1973, 20, 513-518). The correspondence of the constructs measured by the VP1 for potential high school dropouts and college students was found to be substantially the same using the factor-relating procedure of Kaiser, Hunka, and Bianchini (In H. J. Eysenck & S. B. G. Eysenck (Eds.), Personality structure and measurement. San Diego, Calif.: Knapp, 1969, pp. 333-343). These results indicate that Holland’s theory is appropriate for potential high school dropouts and, by implication, for other high school students.
Holland (1973) has proposed a theory of vocational choice in terms of personality types which has received considerable support (e.g., Wakefield & Doughtie, 1973; Williams, 1972; Osipow, Ashby, & Wall, 1966). The Vocational Preference Inventory (VPI) (Holland, 1970) is the most frequently used instrument for measuring the constructs in Holland’s theory. The VP1 is a straightforward, nonthreatening instrument by which vocational interests may be indicated. The measure consists of 160 occupational titles. The testee is asked to indicate in which of the occupations listed he would like to be engaged and which he would not like. Wakefield and Doughtie (1973) have proposed a model-testing procedure to investigate the construct validity of Holland’s theory. This procedure examines the relationships among the constructs in factor space for correspondence with Holland’s hexagonal model of these relationships. The construct validity of Holland’s theory has been strongly supported for college populations using this procedure (Wakefield & Doughtie, 1973; Wakefield, Yom, Doughtie, Chang, & Alston, 1975). Kaiser, Hunka, and Bianchini (1969) have noted that the same instruments used with different populations may not measure the same variRequests for reprints should be sent to Dr. EugeneB. Doughtie, Departmentof psy&ology, University of Houston, 3801 Cullen Boulevard, Houston, TX 77004. 35 Copyright 0 1977 by Academtc Press. Inc All rights of reproducrmn m any form reserved.
ISSN 000-8791
36
CUNNINGHAM ETAL
ables and have presented a method of determining the degree of correspondence between the factor structures of different populations. Using the factor-relating procedure proposed by Kaiser et al. (1969), Alston, Wakefield, Doughtie, and Bobele (1976) reported that the constructs measured by the VP1 are substantially the same for male and female college students, and Yom, Doughtie, Chang, Alston, and Wakefield (1975) reported that the constructs measured by the VPI are very similar for black and white college students. The present study addresses the question of whether or not the VP1 can be used with potential high school dropouts. The subjects for this study were chosen because their academic orientation and educational background are the maximally different we can find from the college population previously studied (Alston et al., 1976). It is reasoned that if Holland’s theory holds for this extreme group then one might feel more sanguine in using Holland’s theory when counseling other high school students who are less dissimilar to the college group. In addition, many potential high school dropouts are encouraged to participate in vocationally oriented programs and because the validity of Holland’s theory with such a population has received little investigation. The fact that potential high school dropouts are less academically oriented raises the question of whether or not Holland’s theory of vocational interests, which has been supported for college students, is appropriate for counseling potential high school dropouts enrolled in vocational programs. Wakefield and Doughtie’s (1973) model-testing procedure was used to assess the relations among interest types to learn if they conform to the hypothesized geometric model. This is one of the many tests of construct validity needed to evaluate the usefulness of the theory and its classification scheme. The factor-relating procedure of Kaiser et al. (1969) was used to determine the degree of correspondence between the constructs measured by the VP1 for potential high school dropouts and college students. METHOD Subjects. The high school sample consisted of 252 students and constituted the total number of students enrolled in a special learning center for potential dropouts. One hundred forty-nine were males and 103 were females. The mean chronological age was 16.9 years, with a standard deviation of 1.36 years. The group contained Anglo-, Black, and Mexican Americans. The college sample with which the high school sample was compared was the sample reported by Alston et al. (1976) and consisted of 174 students, 82 males and 92 females. The sample was predominately Anglo-American, with a mean chronological age of 23.6 years and a standard deviation of 5.7.
VP1 WITH HIGH SCHOOL STUDENTS
37
Analysis. The Wakefield and Doughtie (1973) model-testing procedure was used to test Holland’s hexagonal model, This procedure requires computing the Pearson product-moment correlations between the constructs measured by the VPI, factor-analyzing the resulting correlation matrix by the principal components method (Harman, 1967), and computing the distances between each pair of constructs in the resulting factor space. After the distances between pairs of constructs are computed, these distances are compared with each other in relation to Holland’s model of construct relationships. Holland’s hexagonal model involves 54 independent distance comparisons between pairs of constructs. The normal approximation of the binomial sampling distribution requires that 34 of the 54 comparisons be in the predicted direction to reject the hypothesis of a random arrangement of the constructs in Holland’s model at the .05 level of significance. Thirtyseven of the 54 construct pair comparisons must be as predicted for significance at the .Ol level. The Kaiser et al. (1969) factor-relating procedure was used to measure the correspondence of the constructs measured by the VP1 for high school and college students. This procedure involved factor-analyzing the correlation matrix of VP1 constructs by the principal components procedure (Harman, 1967) separately for each group. The resulting factor matrices were then compared using the factor-relating procedure of Kaiser et al. This computation was accomplished using a computer program by Veldman (1967). The cosines obtained between the test vectors are interpreted as correlation coefficients and indicate the degree to which the VP1 scales measure the same constructs for both groups. The mean of these cosines indicates the extent to which the test as a whole measures the same constructs for both groups. RESULTS
AND DISCUSSION
Of the 54 distance comparisons between the constructs in Holland’s hexagonal model for high school students, 40 were consistent with Holland’s model of personality types. The z score corresponding to 40 correct observations is 3.402 (p < .OOl). These results support the arrangement of the constructs as shown in Holland’s model. The cosines of the 11 VP1 scales between the potential high school dropouts and college student groups can be seen in Table 1. The mean of the six constructs in Holland’s theory is .95. This is evidence that the VP1 measures largely the same constructs for both groups. The findings that Holland’s hexagonal model holds for potential high school dropouts and that the constructs measured by the VP1 are substantially the same for both potential high school dropouts and college students provide additional support for Holland’s theory. These findings also
38
CUNNINGHAM
ET AL.
TABLE I Cosines between Test Vectors for Potential High School Dropouts and College Students” Scale
Cosine
Realistic Intellectual Social Conventional Enterprising Artistic
.99 .95 .92 .89 .89 .94
Scale Self-control Masculinity Status Infrequency Acquisition
Cosine .96 .99 .98 .97 1.00
(I Cosines are rounded to two decimal places.
imply that Holland’s theory should apply to other high school students who are less dissimilar to the college comparison group than the potential high school dropouts. More important, the results support the use of the VP1 with these students to measure their vocational interests and suggest that the interpretation of VP1 profiles is the same for both potential high school dropouts and college students. REFERENCES Alston, H. L., Wakefield, J. A., Jr., Doughtie, E. B., & Bobele, R. M. Correspondence of constructs in Holland’s theory for male and female college students. Journal of Vocational Behavior,
1976, 8, 85-88.
Harman, H. H. Modern factor analysis. Chicago: University of Chicago Press, 1967. Holland, J. L. Making vocational choices: A theory of careers. Englewood Cliffs, N. J.: PrenticeHall, 1973. Holland, J. L. Manualfor the Vocational Preference Inventogl. Palo Alto, Calif.: Consulting Psychologists Press, 1970. Kaiser, H. F., Hunka, S., & Bianchini, J. Relating factors between studies based upon different individuals. In H. J. Eysenck & S. B. G. Eysenck (Eds.), Personality structure and measurement. San Diego, Calif.: Knapp, 1969, pp. 333-343. Osipow, S. H., Ashby, J. D., & Wall, H. W. Personality types and vocational choice: A test of Holland’s theory. Personnel and Guidance Journal, 1966, 45, 37-42. Veldman, D. J. Fortran programming for rhe behatpiora/ sciences. New York: Holt, Rinehart & Winston, 1967. Wakefield, J. A., Jr., & Doughtie, E. B. The geometric relationship between Holland’s personality typology and the Vocational Preference Inventory. Journal of Counseling Psychology,
1973, 20, 513-518.
Wakefield, J. A., Jr., Yom, B. L., Doughtie, E. B., Chang, W. C., & Alston, H. L. The geometric relationship between Holland’s personality typology and the Vocational Preference Inventory for blacks. Journal of Counseling Psychology, 1975. 22, 58-60. Williams, C. M. Occupational choice of male graduate students as related to values and personality: A test of Holland’s theory. Journal of Vocational Behavior, 1972,2,39-46. Yom, B. L., Doughtie, E. B., Chang, W. C., Alston, H. L., & Wakefield, J. A., Jr. The factor structure of the Vocational Preference Inventory for black and white college students. Journal of Vocational Behavior, 1975, 6, 15-18. Received: March 8, 1976.