Understanding Construct Validity: Convergent and Discriminant Principles

1. Convergent and Discriminant Validity

2. The Convergent Principle Measures of constructs that are related to each other should be strongly correlated.

3. Self-esteem construct Item 1 Item 2 Item 3 Item 4 How It Works Theory

4. Self-esteem construct Item 1 Item 2 Item 3 Item 4 How It Works Theory You theorize that the items all reflect self-esteem.

5. Self-esteem construct Item 1 Item 2 Item 3 Item 4 How It Works Theory 1.00 .83 .89 .91 .83 1.00 .85 .90 .89 .85 1.00 .86 .91 .90 .86 1.00 Observation

6. Self-esteem construct Item 1 Item 2 Item 3 Item 4 How It Works Theory 1.00 .83 .89 .91 .83 1.00 .85 .90 .89 .85 1.00 .86 .91 .90 .86 1.00 The correlations provide evidence that the items all converge on the same construct. Observation

7. The Discriminant Principle Measures of different constructs should not correlate highly with each other.

8. Self-esteem construct SE1 SE2 How It Works Theory Locus-of-control construct LOC1 LOC2

9. Self- esteem construct SE1 SE2 How It Works You theorize that you have two distinguishable constructs. Theory Locus-of-control construct LOC1 LOC2

10. Self-esteem construct SE1 SE2 How It Works Theory Locus-of-control construct LOC1 LOC2 rSE1, LOC1 = .12 rSE1, LOC1 = .09 rSE1, LOC1 = .04 rSE1, LOC1 = .11 Observation

11. Self-esteem construct SE1 SE2 How It Works Theory Locus-of-control construct LOC1 LOC2 rSE1, LOC1 = .12 The correlations provide evidence that the items on the two tests discriminate. rSE1, LOC1 = .09 rSE1, LOC1 = .04 rSE1, LOC1 = .11 Observation

12. Putting It All Together Convergent and Discriminant Validity

13. We have two constructs. We want to measure self-esteem and locus of control. Theory Self-esteem construct Locus-of-control construct

14. We have two constructs. We want to measure self-esteem and locus of control. Theory Self-esteem construct Locus-of-control construct SE1 SE2 SE3 LOC1 LOC2 LOC3 For each construct, we develop three scale items; our theory is that items within the construct will converge and Items across constructs will discriminate.

15. SE1 SE2 SE3 LOC1 LOC2 LOC3 1.00 .83 .89 .02 .12 .09 .83 1.00 .85 .05 .11 .03 .89 .85 1.00 .04 .00 .06 .02 .05 .04 1.00 .84 .93 .12 .11 .00 .84 1.00 .91 .09 .03 .06 .93 .91 1.00 SE1 SE2 SE3 LOC1 LOC2 LOC3 Theory Self-esteem construct Locus-of-control construct SE1 SE2 SE3 LOC1 LOC2 LOC3 Observation

16. SE1 SE2 SE3 LOC1 LOC2 LOC3 1.00 .83 .89 .02 .12 .09 .83 1.00 .85 .05 .11 .03 .89 .85 1.00 .04 .00 .06 .02 .05 .04 1.00 .84 .93 .12 .11 .00 .84 1.00 .91 .09 .03 .06 .93 .91 1.00 SE1 SE2 SE3 LOC1 LOC2 LOC3 Theory Locus-of-control construct Self-esteem Construct Green and red correlations are Convergent; yellow are Discriminant. SE1 SE2 SE3 LOC1 LOC2 LOC3 Observation

17. SE1 SE2 SE3 LOC1 LOC2 LOC3 1.00 .83 .89 .02 .12 .09 .83 1.00 .85 .05 .11 .03 .89 .85 1.00 .04 .00 .06 .02 .05 .04 1.00 .84 .93 .12 .11 .00 .84 1.00 .91 .09 .03 .06 .93 .91 1.00 SE1 SE2 SE3 LOC1 LOC2 LOC3 Theory Self-esteem construct Locus-of-control construct SE1 SE2 SE3 LOC1 LOC2 LOC3 The correlations support both convergence and discrimination, and therefore construct validity. Observation