Week 7

Question 1

how strong is your correlation

Answer 1

direction
- if r is above zero (1>=r>0), your correlation is positive
- if r is below zero (-1<=r<0), your correlation is negative
strength
- if r is close to one (r~1), your correlation is strong
- if r is close to zero (r~0), your correlation is weak

Question 2

how much variance is explained by the correlation

Answer 2

• if r^2 is close to one (r^2~1), your correlation explains a lot of variance
• if r^2 is close to zero (r^2~0), your correlation explains only a little variance

Question 3

what is r^2 sometimes known as

Answer 3

coefficient of determination

Question 4

slopes on graphs

Answer 4

y=mx+c