- Email: [email protected]
Assessing the Structure of Vocational Interests among Bolivian University Students
JOURNAL OF VOCATIONAL BEHAVIOR ARTICLE NO.
48, 96–106 (1996)
0010
Assessing the Structure of Vocational Interests among Bolivian University Students CYNTHIA E. GLIDDEN-TRACEY AND MARIANELA I. PARRAGA Southern Illinois University at Carbondale Ninety-eight Bolivian university students completed the Spanish version of Holland’s Self-Directed Search. The fit of three different structural models of vocational interest (Holland’s [1973] circumplex, Gati’s [1979] three group partition, and Rounds and Tracey’s [in press] three group partition) were fit to the correlations among the RIASEC scales using the randomization test of hypothesized order relations (Hubert & Arabie, 1987). Nonsignificant probabilities and low correspondence indices were obtained for all three models. These results indicate poor model fit, suggesting that none of these models adequately characterize the structure of vocational interests of the Bolivian students sampled. Multidimensional scaling was used to depict the structure of the Bolivian sample’s vocational interests in two dimensions. q 1996 Academic Press, Inc.
Do the psychological components of human occupations differ from one culture to another? Holland’s well-known model of vocational interests, developed in Anglo-America and now being assessed for American minority populations, posits six general occupational types—Realistic, Investigative, Artistic, Social, Enterprising, and Conventional (RIASEC; Holland, 1973, 1985)— arranged in a hexagon so that the physical distance modeled between each type represents the conceptual relations between them. When such a configuration of prototypes is specified with corresponding mathematical relations between types, the model is called a circumplex (Guttman, 1954). Several authors have noted that Holland’s interest model meets the requirements of a circumplex (Fouad, Cudeck, & Hansen, 1984; Hogan, 1983; Tracey & Rounds, 1992). Numerous studies have found support for the construct validity of Holland’s structural hypothesis on samples drawn in the United States (e.g., Bobele et al., 1976; Gati, 1984, 1991; Holland, 1987; Rounds, Davison, & Dawis, 1979; Tuck & Keeling, 1980; Tracey & Rounds, 1992), but the cultural universality This paper was presented at the annual meeting of the American Psychological Association, Los Angeles, 1994. Correspondence and reprint requests should be addressed to Cynthia GliddenTracey, Ph.D., Department of Psychology, Southern Illinois University, Carbondale, IL 629016502. 96 0001-8791/96 $12.00 Copyright q 1996 by Academic Press, Inc. All rights of reproduction in any form reserved.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
97
of Holland’s model remains an open question. Indeed, in a structural metaanalysis of RIASEC data, Rounds and Tracey (in press) found little support for Holland’s circumplex across 96 RIASEC matrices from a culturally diverse set of samples drawn from 19 nations. Additional structural investigations of samples from cultures not represented in Rounds and Tracey’s meta-analysis are needed to extend our understanding of cultural similarities and differences in the structure of vocational interests. The purpose of the present study was to assess the structure of RIASEC types on Bolivian university students, a group as yet unexamined in the vocational interest literature. The question of cultural differences in the structure of vocational interests is especially relevant as interest measures are being translated into other languages and administered to non-Anglo-American populations for research and counseling purposes. For example, a Spanish version of the Strong Interest Inventory has been developed and validated on Hispanic-American samples (Fouad, Cudeck, & Hansen, 1984). A Spanish translation of the Self-Directed Search Form E (SDS-S; Holland, 1979) is also widely used. The assumption underlying the use of these adapted measures is that the vocational interest model they measure is generalizable across cultures. It has not been empirically demonstrated, however, that the RIASEC model these instruments measure has equal utility for describing the interests of Spanish-speaking populations. Some attention has been paid in the literature to the cultural generalizability of Holland’s model, but the findings have been equivocal. Holland (1985) and Hansen (1987) both reviewed this literature and concluded that the circular structure of vocational interests is culturally invariant. In a special issue of the Journal of Vocational Behavior (Tinsley, 1992), two featured articles (Fouad & Dancer, 1992; Swanson, 1992) reported studies of the structure of interests in two particular non-Caucasian samples. Fouad and Dancer compared MDS-derived interest configurations for U.S. vs Mexican engineers and engineering students. Swanson used MDS analysis to assess the interest structure among a large sample of African American college students. The authors of both studies concluded that although a few minor variations to interest structures based on U.S. sample scores were observed in these culturally different populations, their results generally suggest the cross-cultural applicability of Holland’s model. These authors also acknowledge the need for more research to answer these comparative structural questions, essentially concurring with reactions published in the same issue (Chartrand, 1992; Dawis, 1992; Hansen, 1992; Subich, 1992). Rounds and Tracey (in press) note that the conclusions that can be drawn from many cross-cultural structure of interest studies are limited by methodological problems. Many studies of the structure of interests have employed one of two methods: (a) eyeballing the correlation matrix or spatial representation of the data, or (b) conducting the binomial test of predicted orders proposed by Wakefield and Doughtie (1973). Obviously visual inspection can yield unreliable conclusions. Hubert and Arabie (1987) demonstrated that Wakefield and Doughtie’s (1973) use of the binomial test inappropriately violates the assump-
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
98
GLIDDEN-TRACEY AND PARRAGA
FIG. 1. Representations of three models of RIASEC personality types (R, realistic; I, investigative; A, artistic; S, social; E, enterprising; C, conventional). Reprinted by permission, from Rounds and Tracey (in press). q American Psychological Association.
tion of independent order relations among occupational types. To remedy this problem, Hubert and Arabie (1987) proposed the randomization test of hypothesized orders. Rounds, Tracey, and Hubert (1992) provided detailed explanation of this procedure for conducting valid tests of any hypothesized structure. The methodological strength and interpretive value of this approach was illustrated in a series of studies, comparing different formulations (circular order versus circumplex) of the RIASEC model (Rounds et al., 1992), Holland’s order and circumplex models with Gati’s (1991) three-group partition model (Tracey & Rounds, 1993), and the structures of vocational interest among culturally varied samples (Rounds & Tracey, in press). Berry (1989) suggested that a construct with demonstrated validity in one culture can be transported to another culture as an ‘‘imposed’’ (or hypothetically presumed) construct. Assuming translation and measurement equivalence, the finding of conceptually and empirically similar constructs in two culturally distinct samples supports the assumption of a cultural universal. The present study uses this rationale and the methods proposed by Hubert and Arabie (1987) to examine the structure of SDS-S scores (representing Holland’s model of vocational interests ‘‘imposed’’ on a culturally different sample) obtained from a sample of Bolivian undergraduates. Three models (see Fig. 1) were tested for goodness of fit: Holland’s circumplex hypothesis, Gati’s hierarchical model of vocational interests, and Rounds and Tracey’s (in press) alternative partition model. METHOD
Participants Data were collected from 98 students (43 men, 52 women, 2 gender unspecified) attending one of the major universities in Bolivia. Students were re-
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
99
cruited by volunteer assistants of the primary investigators. The 5 male and 5 female assistants pretested the SDS-S to identify potential questions, and then solicited volunteer participants for the study by making announcements in classrooms with the instructor’s consent. Participants ranged in age from 16 to 34 (mean Å 21, SD Å 2.6). Forty different courses of study were represented in the sample. Instrument The SDS-S is the Spanish translation of Holland’s (1979) Self-Directed Search-Form E. Form E is an abbreviated version of the Self-Directed Search (SDS) developed for poor readers by eliminating the SDS items with complex wording and/or the lowest item to interest scale correlations (Holland, 1994, personal communication). Reliability coefficients for Form E indicate moderate to high reliability (range .56 to .92, with 89% of the 36 subscale KR-8 coefficients ú .72) and do not differ substantially from the reliabilities obtained for the full SDS (Holland, 1985). Form E is currently the only version of the SDS available in Spanish. The SDS-S yields six subscale scores assessing the degree to which the respondent endorses interests that are Realistic, Investigative, Artistic, Social, Enterprising, and Conventional. Because no reliability estimates for the SDSS are reported in the SDS manual (Holland, 1985; 1987), split-half reliability coefficients were computed on the RIASEC scores of the present sample. This analysis yielded reliability estimates (adjusted using the Spearman– Brown formula) for R Å .88, I Å .88, A Å .89, S Å .90, E Å .91, and C Å .95. Glidden-Tracey and Greenwood (1994) assessed the linguistic equivalence of the Spanish and English versions of the SDS Form E by comparing the scores of a sample (n Å 36) on the original English version and on a Spanish to English back translation of the SDS-S. Results of a randomization test of difference in model to data fit were nonsignificant, indicating that the SDSS is an adequate translation. The SDS was chosen for this study because it can be administered and interpreted by the respondent. No trained counselors were available in Bolivia to score and interpret the results to interested participants, so the self-explanatory nature of the SDS seemed advantageous compared to other Spanish language career inventories. Procedures Participants were given a packet of instruments to complete, including a demographic questionnaire, the SDS-S, and two personality measures unrelated to the present study. The packets were return addressed to the second author’s residence in Bolivia. One hundred ten packets were distributed and 98 returned, yielding an 89% response rate. This remarkable compliance may be explained by the informal comment of one of the researcher’s assistants,
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
100
GLIDDEN-TRACEY AND PARRAGA
who noted that students were excited about participating in research associated with a university in ‘‘los Estados Unidos.’’ Analysis The Bolivian students’ data were analyzed using the RANDORD program to compare the correlational structures derived from this sample with those predicted from vocational interest theory. RANDORD was developed by Tracey (1991) to test the fit of any specified structural model to the data using Hubert and Arabie’s (1987) randomization test of hypothesized order. We tested Holland’s circumplex, Gati’s three group partition, and Rounds and Tracey’s three group partition model. Each of these models specifies a number of predictions about the relative magnitude of correlations among a matrix of RIASEC interest scores, in this case derived from the SDS-S subscales (see Tracey & Rounds, 1993). Holland’s circumplex model predicts that correlations for the six adjacent types (RI, IA, AS, SE, EC, CR) should be greater than correlations among alternate types (RA, AE, ER, IS, SC, and CI), which in turn should be greater than correlations among opposite types on the circumplex (RS, IE, and AC). Holland’s specifications yield 72 unique order predictions (Tracey & Rounds, 1993). Gati’s model collapses the RIASEC types into three clusters [(R, I), (A, S), and (E, C)]. Gati (1982) predicts that the correlations within clusters should be greater than correlations among types that are not members of the same cluster. This model makes only 36 unique order predictions, implying that the correlations among other possible pairs of types are inconsequential (Tracey & Rounds, 1993). The alternative partition model (Rounds & Tracey, in press) addresses the observed discontinuity between the Artistic interest type and other Holland types (e.g., Fouad & Dancer, 1992; Swanson, 1992). Although Holland proposes a relation between Artistic (A) and Social (S) interests of the same magnitude as that between other adjacent types, and Gati considers A and S to be one of three central clusters, unconstrained cluster analysis of 104 RIASEC matrices (Tracey & Rounds, 1993) yielded an SEC cluster across two-, three-, and four-cluster solutions. Rounds and Tracey (in press) theoretically justify an SEC cluster on the grounds that ‘‘the E type is linked to the S type through involvement with people and the E and C types are linked through business activity’’ (page 10). Thus, the alternative partition model makes 44 order predictions regarding three interest clusters: [(R, I), (A), (S, E, C)]. Correlations between Holland types within each cluster are predicted to be greater than correlations among types in different clusters. In this study, we assessed the adequacy of Holland’s, Gati’s, and Rounds and Tracey’s models in accounting for the structure of Bolivian students’ interests. The fit of each model to the data is compared to the fit of the model to all possible permutations of the rows and columns of the correlation matrix. This analysis provides an exact probability of obtaining the model-to-data fit, and
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
101
also gives the correspondence index (CI) as an interpretive aid. The correspondence index is the number of observed correlations in the RIASEC proximity matrix that agree with the model predictions minus the number of disagreements divided by the total number of predictions made for that model. Rounds, Tracey, and Hubert (1992) provided a detailed example of this analysis. Research on structural differences across gender has yielded ambiguous results. Hansen, Collins, Swanson and Fouad (1993) concluded that the structure of interest is different for men and women. The opposite conclusion of no gender difference in interest structures was reached by Rounds (in press) and by Tracey and Rounds (1993). In light of the equivocal findings, the present data were analyzed for the entire sample and separately for the female and male subsamples to assess the possibility of gender differences in the structure of interests. RESULTS
The randomization test of the fit of Holland’s circumplex model to the data indicated that 32 of the 72 model predictions were confirmed, yielding a probability level of .67 and a correspondence index of 00.11. For Gati’s model, 22 of 36 predictions were confirmed (p Å .27) with a correspondence index of .22. The test of Rounds and Tracey’s alternative partition model produced 17 confirmed predictions out of a possible 44 (p Å .77 and CI Å 0.23). Testing the fit of Holland’s structure of interests separately by gender yielded similar, nonsignificant results. For the matrix of men’s scores, 31 of Holland’s 72 order predictions were met (p Å .80, CI Å 0.14). For the Bolivian women’s scores, 35 predictions were confirmed (p Å .57, CI Å 0.03). A further examination of the structural fit between Holland’s model and the Bolivian data was conducted using three-way MDS. The solution was constrained so that RIASEC scores would be a perfect circle in two dimensions, as Holland’s circumplex model predicts. The variance accounted for by this solution was only .20. Three-way MDS allowed separate estimation of the variance accounted for in the subsamples of women (.26) and men (.14). The finding that none of the theoretical interest models we tested fit the Bolivian data (either combined or by gender) raised exploratory questions about the actual structure of these vocational interest scores. Nonmetric multidimensional scaling analysis was conducted to depict the structure of the Bolivian interest data in one, two, and three dimensions. Nonmetric scaling procedures are used when, as in this case, investigators are interested in the rank order of proximities in a matrix, rather than in the numerical properties of the proximity data (Kruskal & Wish, 1978). Kruskal and Wish suggest that values of stress (which assess the degree of fit between the dimensional model and the data) less than .05 indicate adequate fit. For the one-dimensional solution, stress Å .043. In both two and three dimensions, stress õ .001. Thus although a case could be made for representing the Bolivian interest structure in one dimension, the two dimen-
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
102
GLIDDEN-TRACEY AND PARRAGA
FIG. 2. Two-dimensional MDS configuration of SDS-S RIASEC subscale scores for the Bolivian sample (n Å 98) with clustering.
sional model had a lower stress value and parsimoniously represents the data structure in the smallest number of dimensions for that value of stress. The two dimensional solution is also theoretically consistent with literature describing the data/ideas and people/things dimensions of vocational interest, which Prediger and Vansickle (1992) found to be compatible with Holland’s model. Unlike the constrained MDS solution reported above, the configuration of this exploratory two dimensional solution was unconstrained. The two dimensional solution was thus selected as the best representation of this sample’s structure of vocational interests, and is depicted in Fig. 2. Arabie, Carroll, and DeSarbo (1987) recommend using cluster analysis as an aid to interpreting the spatial configuration resulting from MDS analyses. Figure 2 also includes the results of cluster analysis (complete linkage) on the Bolivian data. Inspection of the 2-dimensional MDS configuration indicates a very different structure of interests for the Bolivian sample than the structure predicted on theoretical bases. First, the ordering of types does not conform to the RIASEC model; instead the interest subscales are ordered RISCEA. Second, because R, A, and E scores are clustered together in the Bolivian solution, it appears that four types, rather than Holland’s six, characterize the vocational interests of this sample. Finally, Dimension 1 contrasts Investigative interests with Enterprising and Conventional, while Dimension 2 contrasts Realistic with Social and Conventional interests, which is only partly consistent with Holland’s model.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
103
DISCUSSION
Results of the randomization test of hypothesized order relations among RIASEC types for the Bolivian student sample yielded nonsignificant probabilities and indices of low (near zero) correspondence for the three vocational interest models under investigation. Neither Holland’s, Gati’s, nor Rounds and Tracey’s structure-of-interest models was found to adequately represent the reported interests of these young Bolivians. There was also no evidence to indicate that the models fit any better for either subsample defined by gender composition. The small amount of variance accounted for in the constrained MDS solution also indicates poor fit of a circular model to the Bolivian data. These results suggested that vocational interest models developed in Anglo-America cannot at this point be validly transported to Bolivia. This conclusion, along with the results of Rounds and Tracey (in press), call into question the cultural universality of widely accepted vocational interest models. The unconstrained multidimensional scaling results for the Bolivian sample must be interpreted with caution due to the exploratory nature of the analysis on a sample of unknown representativeness. However, the MDS configuration tentatively suggests that four (rather than six) types characterize these Bolivians’ vocational interests, with Realistic, Artistic, and Enterprising scores relatively undifferentiated. The clustering of R, A, and E is particularly surprising because R, A, and E are alternate types (and thus expected to be less similar than adjacent types) on Holland’s hexagon. This finding could reflect a culturally distinctive scheme for classifying the vocational interests of Bolivian respondents, but this possibility requires further investigation. The sample used in this investigation was relatively small (although not dissimilar to sample sizes reported in a variety of other vocational interest studies). Additionally, random selection of participants was not feasible, raising obvious questions about the generalizability of our findings, although again this limitation on sample selection is typical in the literature on the structure of interests. Alternatively, the RAE cluster may indicate measurement difficulties posed by using the Spanish translation of the SDS-Form E to measure the vocational interests of this non-Anglo-American sample. Despite the publication and distribution of the translated measure, the validity of the translation has not yet been adequately demonstrated. Initial results of Glidden-Tracey and Greenwood’s (1994) backtranslation study are promising, but the results are still preliminary as of this writing. Thus it remains unclear whether the failure to replicate the theoretical structure of vocational interests in this non-Anglo-American sample is attributable to a lack of translation and/or metric equivalence of the Spanish instrument, or to cultural differences in the construction of vocational interests. The results further caution against assumptions that Holland’s model or
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
104
GLIDDEN-TRACEY AND PARRAGA
other tested models of vocational interest have cross-cultural utility. Before Anglo-American models of vocational interest can be validly employed with non-Anglo populations, further research is needed to determine whether available models and/or instruments can be adapted to represent the vocational interests of culturally different populations, or, alternatively, whether cultural differences in the structure of vocational interests require the development of culturally distinct models. Two strategies are recommended to explore the questions raised by the present study. First, the SDS-S could be translated back into English, and the two English versions (original and backtranslated) could be used to assess the alternative forms reliability of the measure. The higher the observed reliability coefficient, the greater the confidence in translation accuracy (Brislin, 1986). Second, groups of samples representing different points on a cultural continuum could be compared in terms of interest structure. For example, the MDS solutions for several samples of Spanish-speaking respondents could be compared with solutions for several samples of native English speakers. The cultural dimension of interest in this example is a linguistic one. Support for the hypothesis of similar structure of interests within a language category but different structures across language groups would suggest that the interpretation of cultural differences in the psychological components of occupational interests is more tenable than the interpretation of measurement inequivalence. While the results of the present study do not definitively clarify the structure of vocational interests in Bolivian university students, they do cast doubt on the appropriateness of using Holland’s, Gati’s, or Rounds and Tracey’s models to conceptualize the vocational interests of these students. The importance of this finding is in its suggestion that vocational psychologists cannot automatically assume that these models can be validly utilized for non-Anglo-American respondents or clients. As of yet, there is no convincing demonstration that vocational interests can be described in culturally universal terms. REFERENCES Arabie, P., Carroll, J. D., & DeSarbo, W. S. (1987). Three-way scaling and clustering. Newbury Park, CA: Sage. Berry, J. W. (1989). Imposed etics-emics-derived etics: The operationalization of a compelling idea. International Journal of Psychology, 24, 721–735. Bobele, R. M., Alston, H. L., Wakefield, J. A., & Doughtie, E. B. (1976). A comparison of Holland’s model using constructs measured by two different methods. Journal of Vocational Behavior, 9, 245–250. Brislin, R. W. (1986). The wording and translation of research instruments. In W. J. Lonner & J. W. Berry (Eds.), Field methods in cross-cultural research (pp. 137–164). Beverly Hills, CA: Sage. Chartrand, J. M. (1992). Research and application using Holland’s typology: Reactions from a scientist-practitioner perspective. Journal of Vocational Behavior, 40, 194–200. Dawis, R. V. (1992). The structure(s) of occupations: Beyond RIASEC. Journal of Vocational Behavior, 40, 171–178.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
105
Fouad, N. A., Cudeck, R., & Hansen, J. C. (1984). Convergent validity of the Spanish and English forms of the Strong-Campbell Interest Inventory for bilingual Hispanic high school students. Journal of Counseling Psychology, 31, 339–348. Fouad, N. A., & Dancer, L. S. (1992). Cross-cultural structure of interests: Mexico and the United States. Journal of Vocational Behavior, 40, 129–143. Gati, I. (1982). Testing models for the structure of vocational interests. Journal of Vocational Behavior, 21, 164–182. Gati, I. (1984). On the perceived structure of occupations. Journal of Vocational Behavior, 25, 1–29. Gati, I. (1991). The structure of vocational interests. Psychological Bulletin, 109, 309–324. Glidden-Tracey, C., & Greenwood, A. K. (1994). A validation study of the Spanish Self-Directed Search using backtranslation procedures. Unpublished manuscript. Guttman, L. R. (1954). A new approach to factor analysis: The radex. In P. Lazarsfeld (Ed.), Mathematical thinking in the social sciences (pp. 258–348). New York: Columbia Univ. Press. Hansen, J. C. (1987). Cross-cultural research on vocational interests. Measurement and Evaluation in Counseling and Development, 19, 163–176. Hansen, J. C. (1992). Does enough evidence exist to modify Holland’s theory to accommodate the individual differences of diverse populations? Journal of Vocational Behavior, 40, 188– 193. Hansen, J. C., Collins, R. C., Swanson, J. L., & Fouad, N. A. (1993). Gender differences in the structure of interests. Journal of Vocational Behavior, 42, 200–211. Holland, J. L. (1973). Making vocational choices: A theory of careers. Englewood Cliffs, NJ: Prentice–Hall. Holland, J. L. (1979). Investigacion auto-dirigida: Guia de Planeacion educacional y vocacional. Odessa, FL: Psychological Assessment Resources. Holland, J. L. (1985). Making vocational choices: A theory of vocational personalities and work environments (2nd ed.). Englewood Cliffs, NJ: Prentice–Hall. Holland, J. L. (1987). 1987 manual supplement for the self-directed search. Odessa, FL: Psychological Assessment Resources. Hogan, R. (1983). A socioanalytic theory of personality. In M. M. Page (Ed.), Nebraska symposium on motivation 1982. Personality: Current theory and research (pp. 55–89). Lincoln, NE: Univ. of Nebraska Press. Hubert, L., & Arabie, P. (1987). Evaluating order hypotheses within proximity matrices. Psychological Bulletin, 102, 172–178. Kruskal, J. B., & Wish, M. (1978). Multidimensional Scaling. Beverly Hills, CA: Sage. Rounds, J. B. (in press). Vocational interests: Evaluating structural hypotheses. In R. V. Dawis & D. Lubinsky (Eds.), Advances in individual differences: New concepts, methods, and findings. Palo Alto, CA: Consulting Psychologists Press. Rounds, J. B., Davison, M. L., & Dawis, R. V. (1979). The fit between Strong–Campbell Interest Inventory General Occupational Themes and Holland’s hexagonal model. Journal of Vocational Behavior, 15, 303–315. Rounds, J. B., Tracey, T. J., & Hubert, L. (1992). Methods for evaluating vocational interest structural hypotheses. Journal of Vocational Behavior, 40, 239–259. Rounds, J. B., & Tracey, T. J. (in press). Cross-cultural structural equivalence of RIASEC models and measures. Journal of Applied Psychology. Subich, J. M. (1992). Holland’s theory: ‘‘Pushing the envelope.’’ Journal of Vocational Behavior, 40, 201–206. Swanson, J. L. (1992). The structure of vocational interests for African-American college students. Journal of Vocational Behavior, 40, 144–157. Tinsley, H. E. A. (1992). Special issue on Holland’s theory. Journal of Vocational Behavior, 40.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
106
GLIDDEN-TRACEY AND PARRAGA
Tuck, B. F., & Keeling, B. (1980). Sex and cultural differences in factorial structure of the SelfDirected Search. Journal of Vocational Behavior, 16, 105–114. Tracey, T. J. (1991). RANDORD: A program for evaluating Holland’s and Gati’s order hypotheses using the randomization test of hypothesized order relationships (Computer program). Champaign, IL: Department of Educational Psychology, University of Illinois at UrbanaChampaign. Tracey, T. J., & Rounds, J. B. (1993). Evaluating Holland’s and Gati’s vocational interest models: A structural meta-analysis. Psychological Bulletin, 113, 229–246. Wakefield, J. A., & Doughtie, E. B. (1973). The geometric relationship between Holland’s personality typology and the Vocational Preference Inventory. Journal of Counseling Psychology, 20, 513–518. Received: April 18, 1994
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
48, 96–106 (1996)
0010
Assessing the Structure of Vocational Interests among Bolivian University Students CYNTHIA E. GLIDDEN-TRACEY AND MARIANELA I. PARRAGA Southern Illinois University at Carbondale Ninety-eight Bolivian university students completed the Spanish version of Holland’s Self-Directed Search. The fit of three different structural models of vocational interest (Holland’s [1973] circumplex, Gati’s [1979] three group partition, and Rounds and Tracey’s [in press] three group partition) were fit to the correlations among the RIASEC scales using the randomization test of hypothesized order relations (Hubert & Arabie, 1987). Nonsignificant probabilities and low correspondence indices were obtained for all three models. These results indicate poor model fit, suggesting that none of these models adequately characterize the structure of vocational interests of the Bolivian students sampled. Multidimensional scaling was used to depict the structure of the Bolivian sample’s vocational interests in two dimensions. q 1996 Academic Press, Inc.
Do the psychological components of human occupations differ from one culture to another? Holland’s well-known model of vocational interests, developed in Anglo-America and now being assessed for American minority populations, posits six general occupational types—Realistic, Investigative, Artistic, Social, Enterprising, and Conventional (RIASEC; Holland, 1973, 1985)— arranged in a hexagon so that the physical distance modeled between each type represents the conceptual relations between them. When such a configuration of prototypes is specified with corresponding mathematical relations between types, the model is called a circumplex (Guttman, 1954). Several authors have noted that Holland’s interest model meets the requirements of a circumplex (Fouad, Cudeck, & Hansen, 1984; Hogan, 1983; Tracey & Rounds, 1992). Numerous studies have found support for the construct validity of Holland’s structural hypothesis on samples drawn in the United States (e.g., Bobele et al., 1976; Gati, 1984, 1991; Holland, 1987; Rounds, Davison, & Dawis, 1979; Tuck & Keeling, 1980; Tracey & Rounds, 1992), but the cultural universality This paper was presented at the annual meeting of the American Psychological Association, Los Angeles, 1994. Correspondence and reprint requests should be addressed to Cynthia GliddenTracey, Ph.D., Department of Psychology, Southern Illinois University, Carbondale, IL 629016502. 96 0001-8791/96 $12.00 Copyright q 1996 by Academic Press, Inc. All rights of reproduction in any form reserved.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
97
of Holland’s model remains an open question. Indeed, in a structural metaanalysis of RIASEC data, Rounds and Tracey (in press) found little support for Holland’s circumplex across 96 RIASEC matrices from a culturally diverse set of samples drawn from 19 nations. Additional structural investigations of samples from cultures not represented in Rounds and Tracey’s meta-analysis are needed to extend our understanding of cultural similarities and differences in the structure of vocational interests. The purpose of the present study was to assess the structure of RIASEC types on Bolivian university students, a group as yet unexamined in the vocational interest literature. The question of cultural differences in the structure of vocational interests is especially relevant as interest measures are being translated into other languages and administered to non-Anglo-American populations for research and counseling purposes. For example, a Spanish version of the Strong Interest Inventory has been developed and validated on Hispanic-American samples (Fouad, Cudeck, & Hansen, 1984). A Spanish translation of the Self-Directed Search Form E (SDS-S; Holland, 1979) is also widely used. The assumption underlying the use of these adapted measures is that the vocational interest model they measure is generalizable across cultures. It has not been empirically demonstrated, however, that the RIASEC model these instruments measure has equal utility for describing the interests of Spanish-speaking populations. Some attention has been paid in the literature to the cultural generalizability of Holland’s model, but the findings have been equivocal. Holland (1985) and Hansen (1987) both reviewed this literature and concluded that the circular structure of vocational interests is culturally invariant. In a special issue of the Journal of Vocational Behavior (Tinsley, 1992), two featured articles (Fouad & Dancer, 1992; Swanson, 1992) reported studies of the structure of interests in two particular non-Caucasian samples. Fouad and Dancer compared MDS-derived interest configurations for U.S. vs Mexican engineers and engineering students. Swanson used MDS analysis to assess the interest structure among a large sample of African American college students. The authors of both studies concluded that although a few minor variations to interest structures based on U.S. sample scores were observed in these culturally different populations, their results generally suggest the cross-cultural applicability of Holland’s model. These authors also acknowledge the need for more research to answer these comparative structural questions, essentially concurring with reactions published in the same issue (Chartrand, 1992; Dawis, 1992; Hansen, 1992; Subich, 1992). Rounds and Tracey (in press) note that the conclusions that can be drawn from many cross-cultural structure of interest studies are limited by methodological problems. Many studies of the structure of interests have employed one of two methods: (a) eyeballing the correlation matrix or spatial representation of the data, or (b) conducting the binomial test of predicted orders proposed by Wakefield and Doughtie (1973). Obviously visual inspection can yield unreliable conclusions. Hubert and Arabie (1987) demonstrated that Wakefield and Doughtie’s (1973) use of the binomial test inappropriately violates the assump-
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
98
GLIDDEN-TRACEY AND PARRAGA
FIG. 1. Representations of three models of RIASEC personality types (R, realistic; I, investigative; A, artistic; S, social; E, enterprising; C, conventional). Reprinted by permission, from Rounds and Tracey (in press). q American Psychological Association.
tion of independent order relations among occupational types. To remedy this problem, Hubert and Arabie (1987) proposed the randomization test of hypothesized orders. Rounds, Tracey, and Hubert (1992) provided detailed explanation of this procedure for conducting valid tests of any hypothesized structure. The methodological strength and interpretive value of this approach was illustrated in a series of studies, comparing different formulations (circular order versus circumplex) of the RIASEC model (Rounds et al., 1992), Holland’s order and circumplex models with Gati’s (1991) three-group partition model (Tracey & Rounds, 1993), and the structures of vocational interest among culturally varied samples (Rounds & Tracey, in press). Berry (1989) suggested that a construct with demonstrated validity in one culture can be transported to another culture as an ‘‘imposed’’ (or hypothetically presumed) construct. Assuming translation and measurement equivalence, the finding of conceptually and empirically similar constructs in two culturally distinct samples supports the assumption of a cultural universal. The present study uses this rationale and the methods proposed by Hubert and Arabie (1987) to examine the structure of SDS-S scores (representing Holland’s model of vocational interests ‘‘imposed’’ on a culturally different sample) obtained from a sample of Bolivian undergraduates. Three models (see Fig. 1) were tested for goodness of fit: Holland’s circumplex hypothesis, Gati’s hierarchical model of vocational interests, and Rounds and Tracey’s (in press) alternative partition model. METHOD
Participants Data were collected from 98 students (43 men, 52 women, 2 gender unspecified) attending one of the major universities in Bolivia. Students were re-
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
99
cruited by volunteer assistants of the primary investigators. The 5 male and 5 female assistants pretested the SDS-S to identify potential questions, and then solicited volunteer participants for the study by making announcements in classrooms with the instructor’s consent. Participants ranged in age from 16 to 34 (mean Å 21, SD Å 2.6). Forty different courses of study were represented in the sample. Instrument The SDS-S is the Spanish translation of Holland’s (1979) Self-Directed Search-Form E. Form E is an abbreviated version of the Self-Directed Search (SDS) developed for poor readers by eliminating the SDS items with complex wording and/or the lowest item to interest scale correlations (Holland, 1994, personal communication). Reliability coefficients for Form E indicate moderate to high reliability (range .56 to .92, with 89% of the 36 subscale KR-8 coefficients ú .72) and do not differ substantially from the reliabilities obtained for the full SDS (Holland, 1985). Form E is currently the only version of the SDS available in Spanish. The SDS-S yields six subscale scores assessing the degree to which the respondent endorses interests that are Realistic, Investigative, Artistic, Social, Enterprising, and Conventional. Because no reliability estimates for the SDSS are reported in the SDS manual (Holland, 1985; 1987), split-half reliability coefficients were computed on the RIASEC scores of the present sample. This analysis yielded reliability estimates (adjusted using the Spearman– Brown formula) for R Å .88, I Å .88, A Å .89, S Å .90, E Å .91, and C Å .95. Glidden-Tracey and Greenwood (1994) assessed the linguistic equivalence of the Spanish and English versions of the SDS Form E by comparing the scores of a sample (n Å 36) on the original English version and on a Spanish to English back translation of the SDS-S. Results of a randomization test of difference in model to data fit were nonsignificant, indicating that the SDSS is an adequate translation. The SDS was chosen for this study because it can be administered and interpreted by the respondent. No trained counselors were available in Bolivia to score and interpret the results to interested participants, so the self-explanatory nature of the SDS seemed advantageous compared to other Spanish language career inventories. Procedures Participants were given a packet of instruments to complete, including a demographic questionnaire, the SDS-S, and two personality measures unrelated to the present study. The packets were return addressed to the second author’s residence in Bolivia. One hundred ten packets were distributed and 98 returned, yielding an 89% response rate. This remarkable compliance may be explained by the informal comment of one of the researcher’s assistants,
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
100
GLIDDEN-TRACEY AND PARRAGA
who noted that students were excited about participating in research associated with a university in ‘‘los Estados Unidos.’’ Analysis The Bolivian students’ data were analyzed using the RANDORD program to compare the correlational structures derived from this sample with those predicted from vocational interest theory. RANDORD was developed by Tracey (1991) to test the fit of any specified structural model to the data using Hubert and Arabie’s (1987) randomization test of hypothesized order. We tested Holland’s circumplex, Gati’s three group partition, and Rounds and Tracey’s three group partition model. Each of these models specifies a number of predictions about the relative magnitude of correlations among a matrix of RIASEC interest scores, in this case derived from the SDS-S subscales (see Tracey & Rounds, 1993). Holland’s circumplex model predicts that correlations for the six adjacent types (RI, IA, AS, SE, EC, CR) should be greater than correlations among alternate types (RA, AE, ER, IS, SC, and CI), which in turn should be greater than correlations among opposite types on the circumplex (RS, IE, and AC). Holland’s specifications yield 72 unique order predictions (Tracey & Rounds, 1993). Gati’s model collapses the RIASEC types into three clusters [(R, I), (A, S), and (E, C)]. Gati (1982) predicts that the correlations within clusters should be greater than correlations among types that are not members of the same cluster. This model makes only 36 unique order predictions, implying that the correlations among other possible pairs of types are inconsequential (Tracey & Rounds, 1993). The alternative partition model (Rounds & Tracey, in press) addresses the observed discontinuity between the Artistic interest type and other Holland types (e.g., Fouad & Dancer, 1992; Swanson, 1992). Although Holland proposes a relation between Artistic (A) and Social (S) interests of the same magnitude as that between other adjacent types, and Gati considers A and S to be one of three central clusters, unconstrained cluster analysis of 104 RIASEC matrices (Tracey & Rounds, 1993) yielded an SEC cluster across two-, three-, and four-cluster solutions. Rounds and Tracey (in press) theoretically justify an SEC cluster on the grounds that ‘‘the E type is linked to the S type through involvement with people and the E and C types are linked through business activity’’ (page 10). Thus, the alternative partition model makes 44 order predictions regarding three interest clusters: [(R, I), (A), (S, E, C)]. Correlations between Holland types within each cluster are predicted to be greater than correlations among types in different clusters. In this study, we assessed the adequacy of Holland’s, Gati’s, and Rounds and Tracey’s models in accounting for the structure of Bolivian students’ interests. The fit of each model to the data is compared to the fit of the model to all possible permutations of the rows and columns of the correlation matrix. This analysis provides an exact probability of obtaining the model-to-data fit, and
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
101
also gives the correspondence index (CI) as an interpretive aid. The correspondence index is the number of observed correlations in the RIASEC proximity matrix that agree with the model predictions minus the number of disagreements divided by the total number of predictions made for that model. Rounds, Tracey, and Hubert (1992) provided a detailed example of this analysis. Research on structural differences across gender has yielded ambiguous results. Hansen, Collins, Swanson and Fouad (1993) concluded that the structure of interest is different for men and women. The opposite conclusion of no gender difference in interest structures was reached by Rounds (in press) and by Tracey and Rounds (1993). In light of the equivocal findings, the present data were analyzed for the entire sample and separately for the female and male subsamples to assess the possibility of gender differences in the structure of interests. RESULTS
The randomization test of the fit of Holland’s circumplex model to the data indicated that 32 of the 72 model predictions were confirmed, yielding a probability level of .67 and a correspondence index of 00.11. For Gati’s model, 22 of 36 predictions were confirmed (p Å .27) with a correspondence index of .22. The test of Rounds and Tracey’s alternative partition model produced 17 confirmed predictions out of a possible 44 (p Å .77 and CI Å 0.23). Testing the fit of Holland’s structure of interests separately by gender yielded similar, nonsignificant results. For the matrix of men’s scores, 31 of Holland’s 72 order predictions were met (p Å .80, CI Å 0.14). For the Bolivian women’s scores, 35 predictions were confirmed (p Å .57, CI Å 0.03). A further examination of the structural fit between Holland’s model and the Bolivian data was conducted using three-way MDS. The solution was constrained so that RIASEC scores would be a perfect circle in two dimensions, as Holland’s circumplex model predicts. The variance accounted for by this solution was only .20. Three-way MDS allowed separate estimation of the variance accounted for in the subsamples of women (.26) and men (.14). The finding that none of the theoretical interest models we tested fit the Bolivian data (either combined or by gender) raised exploratory questions about the actual structure of these vocational interest scores. Nonmetric multidimensional scaling analysis was conducted to depict the structure of the Bolivian interest data in one, two, and three dimensions. Nonmetric scaling procedures are used when, as in this case, investigators are interested in the rank order of proximities in a matrix, rather than in the numerical properties of the proximity data (Kruskal & Wish, 1978). Kruskal and Wish suggest that values of stress (which assess the degree of fit between the dimensional model and the data) less than .05 indicate adequate fit. For the one-dimensional solution, stress Å .043. In both two and three dimensions, stress õ .001. Thus although a case could be made for representing the Bolivian interest structure in one dimension, the two dimen-
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
102
GLIDDEN-TRACEY AND PARRAGA
FIG. 2. Two-dimensional MDS configuration of SDS-S RIASEC subscale scores for the Bolivian sample (n Å 98) with clustering.
sional model had a lower stress value and parsimoniously represents the data structure in the smallest number of dimensions for that value of stress. The two dimensional solution is also theoretically consistent with literature describing the data/ideas and people/things dimensions of vocational interest, which Prediger and Vansickle (1992) found to be compatible with Holland’s model. Unlike the constrained MDS solution reported above, the configuration of this exploratory two dimensional solution was unconstrained. The two dimensional solution was thus selected as the best representation of this sample’s structure of vocational interests, and is depicted in Fig. 2. Arabie, Carroll, and DeSarbo (1987) recommend using cluster analysis as an aid to interpreting the spatial configuration resulting from MDS analyses. Figure 2 also includes the results of cluster analysis (complete linkage) on the Bolivian data. Inspection of the 2-dimensional MDS configuration indicates a very different structure of interests for the Bolivian sample than the structure predicted on theoretical bases. First, the ordering of types does not conform to the RIASEC model; instead the interest subscales are ordered RISCEA. Second, because R, A, and E scores are clustered together in the Bolivian solution, it appears that four types, rather than Holland’s six, characterize the vocational interests of this sample. Finally, Dimension 1 contrasts Investigative interests with Enterprising and Conventional, while Dimension 2 contrasts Realistic with Social and Conventional interests, which is only partly consistent with Holland’s model.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
103
DISCUSSION
Results of the randomization test of hypothesized order relations among RIASEC types for the Bolivian student sample yielded nonsignificant probabilities and indices of low (near zero) correspondence for the three vocational interest models under investigation. Neither Holland’s, Gati’s, nor Rounds and Tracey’s structure-of-interest models was found to adequately represent the reported interests of these young Bolivians. There was also no evidence to indicate that the models fit any better for either subsample defined by gender composition. The small amount of variance accounted for in the constrained MDS solution also indicates poor fit of a circular model to the Bolivian data. These results suggested that vocational interest models developed in Anglo-America cannot at this point be validly transported to Bolivia. This conclusion, along with the results of Rounds and Tracey (in press), call into question the cultural universality of widely accepted vocational interest models. The unconstrained multidimensional scaling results for the Bolivian sample must be interpreted with caution due to the exploratory nature of the analysis on a sample of unknown representativeness. However, the MDS configuration tentatively suggests that four (rather than six) types characterize these Bolivians’ vocational interests, with Realistic, Artistic, and Enterprising scores relatively undifferentiated. The clustering of R, A, and E is particularly surprising because R, A, and E are alternate types (and thus expected to be less similar than adjacent types) on Holland’s hexagon. This finding could reflect a culturally distinctive scheme for classifying the vocational interests of Bolivian respondents, but this possibility requires further investigation. The sample used in this investigation was relatively small (although not dissimilar to sample sizes reported in a variety of other vocational interest studies). Additionally, random selection of participants was not feasible, raising obvious questions about the generalizability of our findings, although again this limitation on sample selection is typical in the literature on the structure of interests. Alternatively, the RAE cluster may indicate measurement difficulties posed by using the Spanish translation of the SDS-Form E to measure the vocational interests of this non-Anglo-American sample. Despite the publication and distribution of the translated measure, the validity of the translation has not yet been adequately demonstrated. Initial results of Glidden-Tracey and Greenwood’s (1994) backtranslation study are promising, but the results are still preliminary as of this writing. Thus it remains unclear whether the failure to replicate the theoretical structure of vocational interests in this non-Anglo-American sample is attributable to a lack of translation and/or metric equivalence of the Spanish instrument, or to cultural differences in the construction of vocational interests. The results further caution against assumptions that Holland’s model or
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
104
GLIDDEN-TRACEY AND PARRAGA
other tested models of vocational interest have cross-cultural utility. Before Anglo-American models of vocational interest can be validly employed with non-Anglo populations, further research is needed to determine whether available models and/or instruments can be adapted to represent the vocational interests of culturally different populations, or, alternatively, whether cultural differences in the structure of vocational interests require the development of culturally distinct models. Two strategies are recommended to explore the questions raised by the present study. First, the SDS-S could be translated back into English, and the two English versions (original and backtranslated) could be used to assess the alternative forms reliability of the measure. The higher the observed reliability coefficient, the greater the confidence in translation accuracy (Brislin, 1986). Second, groups of samples representing different points on a cultural continuum could be compared in terms of interest structure. For example, the MDS solutions for several samples of Spanish-speaking respondents could be compared with solutions for several samples of native English speakers. The cultural dimension of interest in this example is a linguistic one. Support for the hypothesis of similar structure of interests within a language category but different structures across language groups would suggest that the interpretation of cultural differences in the psychological components of occupational interests is more tenable than the interpretation of measurement inequivalence. While the results of the present study do not definitively clarify the structure of vocational interests in Bolivian university students, they do cast doubt on the appropriateness of using Holland’s, Gati’s, or Rounds and Tracey’s models to conceptualize the vocational interests of these students. The importance of this finding is in its suggestion that vocational psychologists cannot automatically assume that these models can be validly utilized for non-Anglo-American respondents or clients. As of yet, there is no convincing demonstration that vocational interests can be described in culturally universal terms. REFERENCES Arabie, P., Carroll, J. D., & DeSarbo, W. S. (1987). Three-way scaling and clustering. Newbury Park, CA: Sage. Berry, J. W. (1989). Imposed etics-emics-derived etics: The operationalization of a compelling idea. International Journal of Psychology, 24, 721–735. Bobele, R. M., Alston, H. L., Wakefield, J. A., & Doughtie, E. B. (1976). A comparison of Holland’s model using constructs measured by two different methods. Journal of Vocational Behavior, 9, 245–250. Brislin, R. W. (1986). The wording and translation of research instruments. In W. J. Lonner & J. W. Berry (Eds.), Field methods in cross-cultural research (pp. 137–164). Beverly Hills, CA: Sage. Chartrand, J. M. (1992). Research and application using Holland’s typology: Reactions from a scientist-practitioner perspective. Journal of Vocational Behavior, 40, 194–200. Dawis, R. V. (1992). The structure(s) of occupations: Beyond RIASEC. Journal of Vocational Behavior, 40, 171–178.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
BOLIVIAN INTEREST STRUCTURE
105
Fouad, N. A., Cudeck, R., & Hansen, J. C. (1984). Convergent validity of the Spanish and English forms of the Strong-Campbell Interest Inventory for bilingual Hispanic high school students. Journal of Counseling Psychology, 31, 339–348. Fouad, N. A., & Dancer, L. S. (1992). Cross-cultural structure of interests: Mexico and the United States. Journal of Vocational Behavior, 40, 129–143. Gati, I. (1982). Testing models for the structure of vocational interests. Journal of Vocational Behavior, 21, 164–182. Gati, I. (1984). On the perceived structure of occupations. Journal of Vocational Behavior, 25, 1–29. Gati, I. (1991). The structure of vocational interests. Psychological Bulletin, 109, 309–324. Glidden-Tracey, C., & Greenwood, A. K. (1994). A validation study of the Spanish Self-Directed Search using backtranslation procedures. Unpublished manuscript. Guttman, L. R. (1954). A new approach to factor analysis: The radex. In P. Lazarsfeld (Ed.), Mathematical thinking in the social sciences (pp. 258–348). New York: Columbia Univ. Press. Hansen, J. C. (1987). Cross-cultural research on vocational interests. Measurement and Evaluation in Counseling and Development, 19, 163–176. Hansen, J. C. (1992). Does enough evidence exist to modify Holland’s theory to accommodate the individual differences of diverse populations? Journal of Vocational Behavior, 40, 188– 193. Hansen, J. C., Collins, R. C., Swanson, J. L., & Fouad, N. A. (1993). Gender differences in the structure of interests. Journal of Vocational Behavior, 42, 200–211. Holland, J. L. (1973). Making vocational choices: A theory of careers. Englewood Cliffs, NJ: Prentice–Hall. Holland, J. L. (1979). Investigacion auto-dirigida: Guia de Planeacion educacional y vocacional. Odessa, FL: Psychological Assessment Resources. Holland, J. L. (1985). Making vocational choices: A theory of vocational personalities and work environments (2nd ed.). Englewood Cliffs, NJ: Prentice–Hall. Holland, J. L. (1987). 1987 manual supplement for the self-directed search. Odessa, FL: Psychological Assessment Resources. Hogan, R. (1983). A socioanalytic theory of personality. In M. M. Page (Ed.), Nebraska symposium on motivation 1982. Personality: Current theory and research (pp. 55–89). Lincoln, NE: Univ. of Nebraska Press. Hubert, L., & Arabie, P. (1987). Evaluating order hypotheses within proximity matrices. Psychological Bulletin, 102, 172–178. Kruskal, J. B., & Wish, M. (1978). Multidimensional Scaling. Beverly Hills, CA: Sage. Rounds, J. B. (in press). Vocational interests: Evaluating structural hypotheses. In R. V. Dawis & D. Lubinsky (Eds.), Advances in individual differences: New concepts, methods, and findings. Palo Alto, CA: Consulting Psychologists Press. Rounds, J. B., Davison, M. L., & Dawis, R. V. (1979). The fit between Strong–Campbell Interest Inventory General Occupational Themes and Holland’s hexagonal model. Journal of Vocational Behavior, 15, 303–315. Rounds, J. B., Tracey, T. J., & Hubert, L. (1992). Methods for evaluating vocational interest structural hypotheses. Journal of Vocational Behavior, 40, 239–259. Rounds, J. B., & Tracey, T. J. (in press). Cross-cultural structural equivalence of RIASEC models and measures. Journal of Applied Psychology. Subich, J. M. (1992). Holland’s theory: ‘‘Pushing the envelope.’’ Journal of Vocational Behavior, 40, 201–206. Swanson, J. L. (1992). The structure of vocational interests for African-American college students. Journal of Vocational Behavior, 40, 144–157. Tinsley, H. E. A. (1992). Special issue on Holland’s theory. Journal of Vocational Behavior, 40.
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB
106
GLIDDEN-TRACEY AND PARRAGA
Tuck, B. F., & Keeling, B. (1980). Sex and cultural differences in factorial structure of the SelfDirected Search. Journal of Vocational Behavior, 16, 105–114. Tracey, T. J. (1991). RANDORD: A program for evaluating Holland’s and Gati’s order hypotheses using the randomization test of hypothesized order relationships (Computer program). Champaign, IL: Department of Educational Psychology, University of Illinois at UrbanaChampaign. Tracey, T. J., & Rounds, J. B. (1993). Evaluating Holland’s and Gati’s vocational interest models: A structural meta-analysis. Psychological Bulletin, 113, 229–246. Wakefield, J. A., & Doughtie, E. B. (1973). The geometric relationship between Holland’s personality typology and the Vocational Preference Inventory. Journal of Counseling Psychology, 20, 513–518. Received: April 18, 1994
m2935$1481
01-16-96 09:29:54
jvba
AP: JVB