A researcher selects a sample from a population with m = 30 and uses the sample to evaluate the effect of a treatment. After treatment, the sample has a mean of M = 32 and a variance of s2= 6. Which of the following would definitely increase the likelihood of rejecting the null hypothesis?
Increase the number of individuals in the sample
Increase the sample mean
Decrease the sample variance
All of the other options will increase the likelihood of rejecting the null hypothesis.