paper 2

Question 1

unit 7 - correlation and regression: what is interpolation?

Answer 1

within the range of known data (more reliable)

Question 2

unit 7 - correlation and regression: what is extrapolation?

Answer 2

outside the range of data

Question 3

unit 7 - correlation and regression: what must scatter graphs have?

Answer 3

a line of best fir that goes through the mean point, preferable through the middle of all points

Question 4

unit 7 - correlation and regression: what is the broken axis used to show?

Answer 4

a gap in the scale

Question 5

unit 7 - correlation and regression: what is an outlier?

Answer 5

points that don’t match the trend of other values

Question 6

unit 7 - correlation and regression: what are cofounders?

Answer 6

confounding variables, meaning that correlation doesn’t always mean causation

Question 7

unit 7 - correlation and regression: what is the PMCC?

Answer 7

a value for the strength of a relationship, value r

Question 8

unit 7 - correlation and regression: what is the value for a perfect positive correlation?

Answer 8

1

Question 9

unit 7 - correlation and regression: what is the value for a strong positive correlation?

Answer 9

close to 1

Question 10

unit 7 - correlation and regression: what is the value for a perfect negative correlation?

Answer 10

-1

Question 11

unit 7 - correlation and regression: what is the value for a strong negative correlation?

Answer 11

close to -1

Question 12

unit 7 - correlation and regression: what is the value for no correlation?

Answer 12

0

Question 13

unit 7 - correlation and regression: what is the general equation for a regression line?

Answer 13

y=a+bx

Question 14

unit 7 - correlation and regression: what does a show?

Answer 14

y intercept

Question 15

unit 7 - correlation and regression: what does the b show?

Answer 15

gradient