setwd("C:/Users/marcogeovanni/Desktop/Modern Guide To Econometrics/Chapter 7")
library(readstata13)
Benefits <- read.dta13("benefits.dta")
attach(Benefits)
summary(Benefits)
## stateur statemb state age
## Min. : 2.200 Min. : 84.0 Min. :11.00 Min. :20.00
## 1st Qu.: 5.700 1st Qu.:150.0 1st Qu.:31.00 1st Qu.:28.00
## Median : 7.200 Median :177.0 Median :55.00 Median :34.00
## Mean : 7.511 Mean :180.7 Mean :52.81 Mean :36.13
## 3rd Qu.: 9.000 3rd Qu.:205.0 3rd Qu.:74.00 3rd Qu.:43.00
## Max. :18.000 Max. :293.0 Max. :95.00 Max. :61.00
## age2 tenure slack abol
## Min. : 40.0 Min. : 1.000 Min. :0.0000 Min. :0.00000
## 1st Qu.: 78.4 1st Qu.: 2.000 1st Qu.:0.0000 1st Qu.:0.00000
## Median :115.6 Median : 3.000 Median :0.0000 Median :0.00000
## Mean :141.8 Mean : 5.664 Mean :0.4761 Mean :0.08243
## 3rd Qu.:184.9 3rd Qu.: 7.000 3rd Qu.:1.0000 3rd Qu.:0.00000
## Max. :372.1 Max. :41.000 Max. :1.0000 Max. :1.00000
## seasonal nwhite school12 male
## Min. :0.00000 Min. :0.0000 Min. :0.0000 Min. :0.0000
## 1st Qu.:0.00000 1st Qu.:0.0000 1st Qu.:0.0000 1st Qu.:1.0000
## Median :0.00000 Median :0.0000 Median :0.0000 Median :1.0000
## Mean :0.03629 Mean :0.1472 Mean :0.1901 Mean :0.7642
## 3rd Qu.:0.00000 3rd Qu.:0.0000 3rd Qu.:0.0000 3rd Qu.:1.0000
## Max. :1.00000 Max. :1.0000 Max. :1.0000 Max. :1.0000
## bluecol smsa married dkids
## Min. :1 Min. :0.0000 Min. :0.0000 Min. :0.0000
## 1st Qu.:1 1st Qu.:0.0000 1st Qu.:0.0000 1st Qu.:0.0000
## Median :1 Median :1.0000 Median :1.0000 Median :0.0000
## Mean :1 Mean :0.6527 Mean :0.6328 Mean :0.4857
## 3rd Qu.:1 3rd Qu.:1.0000 3rd Qu.:1.0000 3rd Qu.:1.0000
## Max. :1 Max. :1.0000 Max. :1.0000 Max. :1.0000
## dykids yrdispl rr rr2
## Min. :0.0000 Min. : 1.000 Min. :0.03861 Min. :0.001491
## 1st Qu.:0.0000 1st Qu.: 2.000 1st Qu.:0.37521 1st Qu.:0.140784
## Median :0.0000 Median : 5.000 Median :0.49045 Median :0.240537
## Mean :0.2217 Mean : 5.204 Mean :0.43837 Mean :0.203440
## 3rd Qu.:0.0000 3rd Qu.: 8.000 3rd Qu.:0.51157 3rd Qu.:0.261708
## Max. :1.0000 Max. :10.000 Max. :0.69118 Max. :0.477725
## head y
## Min. :0.0000 Min. :0.0000
## 1st Qu.:0.0000 1st Qu.:0.0000
## Median :1.0000 Median :1.0000
## Mean :0.6805 Mean :0.6838
## 3rd Qu.:1.0000 3rd Qu.:1.0000
## Max. :1.0000 Max. :1.0000
age2_10 <- age2/10
LPM <- lm(y~rr + rr2 + age + age2_10 + tenure + slack + abol + seasonal + head + married + dkids + dykids + smsa + nwhite + yrdispl + school12 + male + statemb + stateur)
summary(LPM)
##
## Call:
## lm(formula = y ~ rr + rr2 + age + age2_10 + tenure + slack +
## abol + seasonal + head + married + dkids + dykids + smsa +
## nwhite + yrdispl + school12 + male + statemb + stateur)
##
## Residuals:
## Min 1Q Median 3Q Max
## -0.9706 -0.5374 0.2231 0.3347 0.6770
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) -0.0768690 0.1220560 -0.630 0.52887
## rr 0.6288587 0.3842068 1.637 0.10174
## rr2 -1.0190591 0.4809550 -2.119 0.03416 *
## age 0.0157489 0.0047841 3.292 0.00100 **
## age2_10 -0.0145950 0.0060157 -2.426 0.01530 *
## tenure 0.0056531 0.0012152 4.652 3.37e-06 ***
## slack 0.1281283 0.0142249 9.007 < 2e-16 ***
## abol -0.0065206 0.0248281 -0.263 0.79285
## seasonal 0.0578745 0.0357985 1.617 0.10601
## head -0.0437490 0.0166430 -2.629 0.00860 **
## married 0.0485952 0.0161348 3.012 0.00261 **
## dkids -0.0305088 0.0174321 -1.750 0.08016 .
## dykids 0.0429115 0.0197563 2.172 0.02990 *
## smsa -0.0351950 0.0140138 -2.511 0.01206 *
## nwhite 0.0165889 0.0187109 0.887 0.37534
## yrdispl -0.0133149 0.0030686 -4.339 1.46e-05 ***
## school12 -0.0140365 0.0168433 -0.833 0.40468
## male -0.0363176 0.0178142 -2.039 0.04154 *
## statemb 0.0012394 0.0002039 6.078 1.31e-09 ***
## stateur 0.0181479 0.0030843 5.884 4.28e-09 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 0.4501 on 4857 degrees of freedom
## Multiple R-squared: 0.06691, Adjusted R-squared: 0.06326
## F-statistic: 18.33 on 19 and 4857 DF, p-value: < 2.2e-16
plot(fitted(LPM), residuals(LPM), col="blue")
