In a study published in the American Journal of Psychiatry

Question #1

In a study published in the American Journal of Psychiatry (157:737 – 744, May 2000), researchers wanted to measure the effects of alcohol on the development of the hippocampal region in adolescents.  The researchers randomly selected 12 adolescents with alcohol disorders.  They wanted to determine whether the hippocampal volumes in alcoholic adolescents were less than the normal volume of 9.02 cubic centimeters and a standard deviation of 0.7. The sample revealed a mean of 8.10 cubic.  Assume normality and use α = 0.01 level of significance and minitab.  (10 Points)

State the null and alternative hypotheses:

Calculate the test statistic:

Find the p-value:

Decision:

Conclusion:

A study of 74 patients with ulcers was conducted in which they were prescribed 40 mg of a popular acid reducing medication.  After 8 weeks 58 reported ulcer healing.

Give a point estimate for the proportion of people with ulcer healing

The medication manufacturer claims that 85% of patients will see ulcer healing after taking this medication.  Perform a hypothesis test to determine if the percentage is actually less than the manufacturers claim.  (Use minitab and α = 0.05)

State the null and alternative hypotheses:

Calculate the test statistic:

Find the p-value:

Decision:

Conclusion: