Linear Regression

Question 1

Linear regression equation (true)

Answer 1

yi = B0+B1xi +Ei

Question 2

Linear regression equation (Fitted)

Answer 2

yHat = b0+b1x

Question 3

b0

Answer 3

the intercept

Question 4

b1

Answer 4

the slope (rise / run)

Question 5

x

Answer 5

given value of x

Question 6

Correlation

Answer 6

*denoted as r, measures the strength and direction of the line
*between -1 and 1. positive value = rising line, negative = falling line
*r = 0 = no linear relation between X and Y
*closer R is from 1 or -1 the stronger the relation

Question 7

r^2

Answer 7

the variation! if you are given a % in a linear regression problem it is r^2

Question 8

slope equation

Answer 8

b1 = r * (Sy/Sx)

Question 9

Intercept equation

Answer 9

b0 = yBar - b1(xBar)

Question 10

residual

Answer 10

the about of variation we could not predict. Sum of the residuals will equal 0

residual = y - yHat = observed y @ given x - predicted y @ given x

Question 11

Se

Answer 11

different from SE, this is the standard deviation of residuals!

Question 12

confidence interval for slope

Answer 12

b1+- t* (Seb1)

Question 13

confidence interval form mean value of Y

Answer 13

yHat +- t* (Seu)