psychological reserach methods

PART ONE :

For each of the following four studies, indicate
(a) the purpose of the study, and
(b) the type of research method used : observation, case study, survey, the correlational method, experimentation).

If the investigators used the method of experimentation, indicate the independent and dependent variables. Please write in your own words and do not copy from the study descriptions.

1. A physiological psychologist performed a study to determine whether there was a link between nutritional imbalance and aggression. She recruited men of different ages and interviewed them about their past lives. She also collected blood samples from these men to perform a number of analyses. She found that aggressive males with a history of assaults had lower zinc levels and higher cooperation levels.

(A) The purpose of this study was to determine whether there is a relationship between food difference and violent behaviour.
(B) The type of the research method used in t...