A random sample is selected from a normal population
with a mean of μ=50 and a standard deviation of σ=12. After a
treatment is administered to the individuals in the sample, the
sample mean is found to be M=55.
a. If the sample consists of n=16 scores, is the sample
mean sufficient to conclude that the treatment has a
significant effect? Use a two-tailed test with α =0.05. b. If the
sample consists of n=36 scores, is the sample mean sufficient to
conclude that the treatment has a significant effect? Use a
two-tailed test with α =0.05. c. Compare your answers for parts a
and b, explain how the size of the sample influences the
outcome of a hypothesis test.