Select the best answer

If a researcher is using a t-statistic (Independent Samples t Test) to test a null hypothesis about a population, what information is needed from the population to calculate the t-statistic?

a)You must know the population mean.

b)You must know the population variance or standard deviation.

c)You must know the population mean and the variance or standard deviation.

d)Does not require any information about the population.

What is the purpose for post-hoc tests?

a)to determine whether or not a Type I error was committed

b)to determine how much difference exists between the treatments

c)to determine which treatments are significantly different

d)None of the above