Correlation and Power

Question 1

Correlation coefficient

Answer 1

-r
-Strength of linear association between 2 variables

Question 2

Characteristics of correlation

Answer 2

-+ or – shows direction of relationship
–1.00-1.00- degree of linear association, further away from 0 the more associated
-Positive correlation- values move in same direction
-Negative correlation- values move in opposite directions

Question 3

Coefficient of determination

Answer 3

-r^2
-Shared variance between 2 variables

Question 4

Power

Answer 4

Probability of detecting a “real” effect in a study

Question 5

Power analysis

Answer 5

-Happens before study to give you a sample size based on wanted power
-Figure out what you are testing
-Figure out expected effect size
-Set power
-Calculate and get sample size

Question 6

Correlation in real life

Answer 6

Not always used correctly because it must be a linear relationship