?>

library(AER)
library(stargazer)

data(CASchools)
str(CASchools)
C <- CASchools[ , c(11,13)]
str(C)
plot(data=C,read~income)

C$H_income = ifelse( C$income >=27 , C$income-27 ,0 )
str(C)

spline_1 <- lm (data=C, read ~ income+ H_income)
summary(spline_1)

C$N_income <- ifelse( C$income <= 27 , C$income ,27 )

spline_2 <- lm (data=C, read ~ N_income+ H_income)
summary(spline_2)

stargazer(spline_1,spline_2, type = “text”, title = “Spline Regression models”)

ord <- order(C$income)

windows()
plot(data=C, read~income, main=”Spline 1″)
lines(C$income[ord],spline_1$fitted.values[ord],col=’blue’,lwd=2)

windows()
plot(data=C, read~income, main=”Spline 2″)
lines(C$income[ord],spline_2$fitted.values[ord],col=2,lwd=2)

windows()
plot(spline_1,1)

acf(spline_1$residuals[ord]) #按照順序排列

windows()
acf(spline_1$residuals)

 

 

 

221020 計量經濟學_spline
?>