Correlation, Association and Regression

Question 1

Describe a strong positive graph.

Answer 1

Upwards, in a line (roughly)

Question 2

Describe a weak positive graph

Answer 2

Upwards, slightly scattered

Question 3

Describe a no correlation graph

Answer 3

All over, Very scattered

Question 4

Describe a weak negative graph

Answer 4

Downwards, slightly scattered

Question 5

Describe a strong negative graph

Answer 5

Downwards, in a line (roughly)

Question 6

What is Biuariate data?

Answer 6

data which has pairs of value for two variables

Question 7

Does correlation mean causation?

Answer 7

no

Question 8

What is interpolation?

Answer 8

within the data points

Question 9

What is extrapolation?

Answer 9

outside the data points

Question 10

What is the problem with extrapolation?

Answer 10

It isn’t reliable

Question 11

How do you find regression on a calculator?

Answer 11

Calculator - menu - 6 - 2 - fill out table - AC - OPTN - 3

Question 12

How do you calculate the r value using a table?

Answer 12

calculator - menu - 6 - 2 - fill out table - OPTN - 4

Question 13

What are the correlations for r=1, r=0 and r=-1?

Answer 13

r=1 - perfect linear, positive correlation
r=0 - no correlation
r=-1 - perfect linear, negative correlation

Question 14

What is pmcc?

Answer 14

product, moment, correlation, coefficient