Suppose that you have two different X variables (X₁, X₂) that you use to predict scores on Y. What formula would you need to use to assess whether their correlations with Y differ significantly? What information would you need to have to do this test?

Explain each of these null hypotheses.

H_o: ρ = 0

H_o: ρ = .9

H_o: ρ₁ = ρ₂

H_o: ρ_xy = ρ_zy

What test statistic should be used for each of these null hypotheses?