EXPLAINED STATS

You conduct a survey of students' attitudes toward sadistics {sic). You find that liking of sadistics is individually correlated with both the age and the gender of the respondents, and that, for your sample of respondents, age and gender are also correlated.

(a)   What is the question you are trying to answer with these data when you compute a partial  correlation between, say, liking sadistics (the dv) and age (the iv)?

(b)   What is the question you are trying to answer when you compute a semi-partial correlation for these data between, say, liking sadistics (the dv) and gender (the iv)?