The Strong Interest Inventory

1
The Strong Interest Inventory

• Evidence for
• Reliability
• Validity

2
What does the Strong do?

• Compares your responses to items to patterns of
  responses from individuals with differing
  interests and occupations
• Assumptions of the Strong
• Day to day activities typical of an occupation
  are reflected in the interests of people who are
  employed in it
• Test takers who have a similar patterns of
  interests will be satisfied in that occupation if
  they have compatible values and the necessary KSAs

3
Empirical Scale Development

• Select hundreds of items that might distinguish
  the interests of a person by that persons
  occupation
• Administer this test to hundreds of people who
  are representative of many occupations
• Sort out which items discriminated among people
  in different occupational groups
• Construct final test that would provide scores
  describing how a test takers pattern of
  responses corresponds to people in various
  occupations
• E.g., a psychology student could see how closely
  their interests parallel those of working
  psychologists

4
Reliability Estimates

• Test-retest reliabilities range from .80-.90 with
  intervals from 2 weeks to 3 years
• Lower test-retest reliabilities with HS students
  than college students or working adults
• Cronbachs alpha is in low .90s

5
Validity Evidence

• Little psychometric data has been generated by
  independent researchers
• SII correlates with choice of major
• 80 of college students had selected a major that
  was at least moderately related to their
  interests as measured by the SII
• SII correlates with choice of profession
• Musicians score higher on performing arts
• Chemists score high on science
• Elementary school teachers score higher on
  teaching and education

6
Predictive Validity??

• Bizot Goldman (1993) found that interest
  inventories administered in HS predicted neither
  job performance nor job satisfaction 8 years
  later
• Other research has found correlations between SII
  and job satisfaction
• Conclusion
• The value of the SII (and other interest
  inventories) lies in its ability to provide
  greater in-depth vocational and career
  counseling.
• However, one should not assume it predicts
  success or long-term satisfaction

7
Race or Gender Differences

• Fouad Mohler (2004)
• Minimal differences in patterns of interests by
  race
• Significant differences by gender concern about
  possible gender bias
• Ex men score higher on the risk-taking scale
  than women
• Careers that have people who are high risk
  takers engineers, stockbrokers, law enforcement
• tend to be male-dominated
• Careers that have people with low risk taking
  interests
• Dental assistants, Nurse Librarian
• tend to be female dominated
• Does this mean that women wouldnt be satisfied
  as engineers, or just that more men are currently
  engineers and therefore, engineers show more
  risk-taking interests?
• Similarly, would men not be satisfied at being a
  nurse, or is it just that more women are nurses
  and therefore nurses show less risk-taking
  tendencies?