Treatment for depression: Researchers conducted a study of 18patients whose depression had not responded to treatment (Zarate,2006). Half received one intravenous dose of ketamine, hypothesizedquick fix for depression; half received one intravenous dose ofplacebo. Far more of the patients who received ketamine improved,as measured by the Hamilton Depression Rating Scale, usually inless than 2 hours, than patients on placebo.
a.What is the population of interest, and what is the sample inthe study?
b. Was random selection likely used? Explain your answer.
c. Was random assignment likely used? Explain your answer.
d. What is the independent variable and what are the levels?What is the dependent variable?
e. What is the null hypothesis and what is the researchhypothesis?
f. What decision did the researchers make? (Respond using thelanguage of inferential statistics.)
g. If the researchers were incorrect in their decision, whatkind of error did they make? Explain your answer. What are theconsequences of this type of error, both in general and in thesituation?
