A researcher is interested in the relationship between caffeine consumption and level of stress. She has participants keep a diary for one week during which they count the number of cups of coffee, tea, and cola-based soft drinks they consume, as well as recording consumption of chocolate and medications that have caffeine as an ingredient. In addition, participants complete a measure of “daily hassles” experienced during the week.
Answer the following questions for each study described below. (1) Is the study primarily an observational study, a correlation study, or an experiment? Why do