Author Question: An investigator compared the effectiveness of two methods of instruction (A and B) on the math ... (Read 21 times)

amal · **on:** Jun 20, 2018

An investigator compared the effectiveness of two methods of instruction (A and B) on the math achievement of boys and girls. The mean test scores are presented below. What interpretation of these results would be justified?
Method
A B
Gender Boys 40 30
Girls 20 30

a. There was a main effect for method of instruction.
b. There was a main effect for gender.
c. There was an interaction between gender and method of instruction.
d. b and c
e. All of the above are true.

Question 2

The standard error of estimate is equal to zero only if the

a. correlation between X and Y = 0.
b. correlation between X and Y = 1.0.
c. mean on X is equal to the mean on Y.
d. standard deviation of X is equal to the standard deviation of Y.
e. distributions of X and Y are normal.