Lecture 5: Correlational Research

Question 1

what is correlation

Answer 1

a measure of the extent to which two factors can vary together

can be positive or negative

Question 1

What is the goal of correlational research?

Answer 1

to determine if a relation between two variables exists

Question 2

what is a correlation coefficient?

Answer 2

a numerical value that indicates the strength of correlation between two variables

larger the value the stronger the correlation

+1 to -1

Question 3

what is a coefficient of determination?

Answer 3

represented by (italisized r)

allows interpretation of correlation coefficient

the proportion of variance in one variable that is explained by the second variable

two types:
systematic variance: proportion of variability in scores due to exploration of variables

error variance: proportion of change unrelated to the investigated variables

the higher the proportion of systematic variance the stronger the correlation