Clinical psychologists developed a new type of therapy to reduce depression. The psychologists randomly select an incoming patient to receive the new form of therapy instead of the usual therapy. After 4 weeks, the patient scores 34 on a standard depression scale. For those who receive the usual therapy, their depression after 4 weeks is normally distributed with μ = 69.5 and σ = 14.1.
Population 1:
Population 2:
Research Hypothesis:
Null Hypothesis:
To convert the sample score to Z score use: Z = (X - M) / SD
Sample Score: Z=
Is this a one tailed or two tailed hypothesis?
I want to be sure that my result can only happen 1% of the time if the null hypothesis is true. Use the Z-table to find out what the cutoff should be.
Cutoff Z-Score: Z=
Decision:
Interpretation: