Regression Lines + Scatter Diagrams Flashcards
(4 cards)
1
Q
What is the equation for least squares regression line?
A
y=a+bx
2
Q
What do ‘a’ and ‘b’ represent in y=a+bx and what do these tell us?
A
a = the y-intercept. Value of y when x=0
b = the gradient. Increase/decrease of y for every 1 increase in x
3
Q
What point does the regression line always go through?
A
The mean point (x bar, y bar)
4
Q
What is the residual of a regression line?
A
The vertical difference between the points and the regression line
