Q:

Consider the four points​ (10,10), (20,50),​ (40,20), and​ (50,80). the least squares line is modifyingabove y with caret equals 7.0 plus 1.1 xy=7.0+1.1x. explain what​ "least squares"​ means, using these data as a specific example.

Accepted Solution

A:
Answer:The y-intercept of the least squares line is 7 and slope of the line is 1.1. It means x and y are positively related.Step-by-step explanation:Least squares : It is an approach to find a regression line such that the sum of squares of residual(difference between estimated point on the line and data point) is minimum.The given points are (10,10), (20,50),​ (40,20), and​ (50,80).The least squares line is[tex]y=7.0+1.1x[/tex]             .... (1)The general form of least squares line is[tex]y=a+bx[/tex]             .... (2)where, a is y-intercept and b is slope of the line.On comparing (1) and (2) we get[tex]a=7.0,b=1.1[/tex]It means the y-intercept of the least squares line is 7 and slope of the line is 1.1.Slope is positive it means x and y are positively related.