Key Equations

(4-1)

Y=β0+β1X+P

Underlying linear model for simple linear regression.

(4-2)

Y^=b0+b1X

Simple linear regression model computed from a sample.

(4-3)

e=YY^

Error in regression model.

(4-4)

b1=(XX¯)(YY¯)(XX¯)2

Slope in the regression line.

(4-5)

b0=Y¯b1X¯

Intercept in the regression line.

(4-6)

SST = Σ(Y - Y¯)2

Total sums of squares.

(4-7)

SSE = Σe2=Σ(Y - Y^)2

Sum of squares due to error.

(4-8)

SSR=Σ(Y^Y¯)2

Sum of squares due to regression.

(4-9)

SST=SSR+SSE

Relationship among sums of squares in regression.

(4-10)

r2=SSRSST=1SSESST

Coefficient of determination.

(4-11)

r=±r2

Coefficient of correlation. This has the same sign as the slope.

(4-12)

s2=MSE=SSEnk1

An estimate of the variance of the errors in regression; n is the sample size and k is the number of independent variables.

(4-13)

s=MSE

An estimate of the standard deviation of the regression. Also called the standard error of the estimate.

(4-14)

MSR=SSRk

Mean square regression. k is the number of independent variables.

(4-15)

F=MSRMSE

F statistic used to test significance of overall regression model.

(4-16)

Y=β0+β1X1+β2X2++βkXk+ϵ

Underlying model for multiple regression model.

(4-17)

Y^=b0+b1X1+b2X2++bkXk

Multiple regression model computed from a sample.

(4-18)

Adjusted r2=1SSE/(nk1)SST/(n1)

Adjusted r2 used in building multiple regression models.

..................Content has been hidden....................

You can't read the all page of ebook, please click here login for view all page.
Reset