Tests of Differences between Independent Pearson Correlations (4 of 5)

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  1. Since the effect is significant, the null hypothesis is rejected. It is concluded that the correlation between QSAT and GPA is higher for engineering majors than for humanities majors.

  2. An example of a report of this finding is shown below.
    The correlation between QSAT and GPA was significantly higher for the engineering majors (r = 0.61) than for the humanities majors (r =0.35), z = 2.40, p = 0.016.
Summary of Computations
  1. Specify the null hypothesis and an alternative hypothesis.

  2. Compute Pearson's r for both samples. (click here for formula).

  3. Use the r to z' table to convert the r's to z's.

  4. Compute where N1 is the sample size for the first correlation and N2 is the sample size for the second correlation.

  5. Compute .

  6. Use a z table to find the probability value.

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