Exam 2 -Correlation

Question 0

Properties of r

Answer 0

1. Makes no distinction between explanatory and response variab.
2. Requires both variables be QUANTITATIVE

Question 1

Correlation coefficient , r

Answer 1

A number that gives a measure of the direction and strength of linear relationship between two quantitative variables
r - is bounded between -1 and +1
Sign of r denotes direction
r has NO unit of measure
r is affected by outliers

Question 2

Continue Properties of r

Answer 2

Bounded by -1 and +1
Has no unit of measure, doesn’t change when units of measure for x and y are changed
Measures strength of the linear relationship, misleading for curvilinear relationships
Affected by outliers

Question 3

Z score

Answer 3

A measure of the number of standard deviations of a value or observation from the mean

Question 4

Formula of r

Answer 4

r=

Question 5

Correlation r =0

Answer 5

X and y are not linearly related

Question 6

Correlation does not imply

Answer 6

Causation