A researcher gives a group of participants (n = 15) a memory technique to use.

2. A researcher gives a group of participants (n = 15) a memory technique to use.  He finds that they remember on average 20 words (sample standard deviation = 3) while the average number of words remembered in the population is 15.

What is the null hypothesis?

What is the research hypothesis?

Is this a one or two tailed hypothesis?

Which test should you use?  Why?

Calculate the appropriate statistical test.

What is the critical value for α = .05?

What do you conclude?