Conduct an unpaired two-sample t-test for the following data: X̅₁ = 14.8, s₁ = 1.99, n₁ = 52, X̅₁ = 13.2, s₂ = 2.89, n₂ = 233. For this problem, you should use an α value of .01.

a. Explain why an unpaired-samples t-test is appropriate for these data.

b. What is the null hypothesis for these data?

c. Is a one- or a two-tailed hypothesis appropriate for this NHST?

d. Given your response to item (c), what is the appropriate alternative hypothesis for this example?

e. Calculate the degrees of freedom for the data.

f. Find the tcrit value.

g. Calculate the pooled standard deviation and the pooled variance for these data.

h. Calculate the tobs value for the data.

i. Should you reject or retain the null hypothesis?

j. Find a p-value for this example.

k. Should you worry about Type I or Type II error in this example?

l. Calculate and interpret Cohen’s d for this example.

m. Do the data in this example violate any assumptions? If so, which one(s)?