Inter and Extrapolation and Line of best fit

Question 1

Interpolation

Answer 1

Using the line of best fit to estimate data values within the range of data. These values are often reliable.

Question 2

Extrapolation

Answer 2

Using the line of best fit to estimate data values from outside the range of data. These values are less reliable the further away they are from the range of data.

Question 3

The equation of the line of best fit

Answer 3

The line of best fit is also known as the regression line
y=ax+b
gradient =a
y intercept=(0,b)

Question 4

What is the gradient?

Answer 4

The gradient (a) of the line of best fit is the rate of increase of the response (dependent) variable in relation to the explanatory (independent) variable

Question 5

What is the y-intercept?

Answer 5

The y-intercept (b) is the value of the response (dependent) variable when the explanatory (independent) variable is 0

Question 6

How to calculate gradient

Answer 6

y2-y1/x2-x1

Question 7

What is a line of best fit

Answer 7

A straight drawn line so that the plotted points on a scatter diagram are evenly scattered on either side

Question 8

How to draw a line of best fit

Answer 8

To get a good line of best fit, you must draw through the mean point. This is all of the x values added up divided by the amount of values and all of the y values added up divided by the amount of values.