Statistics- Correlation (4)

Question 1

Bivariate data

Answer 1

Has pairs of values for two variables

Question 2

Correleation

Answer 2

Describes the nature of the linear relationship between two variables

Question 3

Causal relationship

Answer 3

If a change in one variable causes a change in the other they have a causal relationship. Context should be considered, two correlating variables aren’t always causal.

Question 4

Least squares regression line

Answer 4

Straight line of best fit which minimizes the sum of the squares of the distance of each data point from the line.

Question 5

Regression line y on x

Answer 5

y=a+bx

- can’t be used for x on y

Question 6

What does the coefficient b represent on the regression line?

Answer 6

Change in y for each unit change in x.

• if positively correlated b is positive
• if negatively correlated b is negative

Question 7

What is an independent variable?

Answer 7

A controlled variable found on the x axis

Question 8

What is a dependent variable?

Answer 8

A measured variable found on the y axis

Question 9

Interpolation

Answer 9

Making predictions for values within the range of x values

Question 10

Extrapolation

Answer 10

Making predictions for values outside the range of x values, it is less accurate.