library(wooldridge)
data(hprice1)
head(force(hprice1),n=5) #mostrar las primeras 5 observaciones
## price assess bdrms lotsize sqrft colonial lprice lassess llotsize lsqrft
## 1 300 349.1 4 6126 2438 1 5.703783 5.855359 8.720297 7.798934
## 2 370 351.5 3 9903 2076 1 5.913503 5.862210 9.200593 7.638198
## 3 191 217.7 3 5200 1374 0 5.252274 5.383118 8.556414 7.225482
## 4 195 231.8 3 4600 1448 1 5.273000 5.445875 8.433811 7.277938
## 5 373 319.1 4 6095 2514 1 5.921578 5.765504 8.715224 7.829630
library(stargazer)
##
## Please cite as:
## Hlavac, Marek (2022). stargazer: Well-Formatted Regression and Summary Statistics Tables.
## R package version 5.2.3. https://CRAN.R-project.org/package=stargazer
options(scipen = 9999)
ModeloHeterocedasticidad <- lm(formula = price~lotsize+sqrft+ bdrms, data = hprice1)
stargazer(ModeloHeterocedasticidad, title = "Modelo Estimado", type = "text", digits = 5)
##
## Modelo Estimado
## ===============================================
## Dependent variable:
## ---------------------------
## price
## -----------------------------------------------
## lotsize 0.00207***
## (0.00064)
##
## sqrft 0.12278***
## (0.01324)
##
## bdrms 13.85252
## (9.01015)
##
## Constant -21.77031
## (29.47504)
##
## -----------------------------------------------
## Observations 88
## R2 0.67236
## Adjusted R2 0.66066
## Residual Std. Error 59.83348 (df = 84)
## F Statistic 57.46023*** (df = 3; 84)
## ===============================================
## Note: *p<0.1; **p<0.05; ***p<0.01
library(stargazer)
Ui <- ModeloHeterocedasticidad$residuals
Mat_X <- model.matrix(ModeloHeterocedasticidad)
MatrizX <- Mat_X[,-1]
VectorY <- hprice1$price
Data.PruebaWhite <- as.data.frame(cbind(Ui,VectorY, MatrizX ))
RegresionAuxiliar <- lm(formula = I(Ui^2)~lotsize+sqrft+bdrms+I(lotsize^2) + I(sqrft^2) + I(bdrms^2) + lotsize*sqrft+lotsize*bdrms+ sqrft*bdrms, data = Data.PruebaWhite)
sumario <- summary(RegresionAuxiliar)
n <- nrow(Data.PruebaWhite)
R2 <- sumario$r.squared
LMw <- n*R2
Gl <- 3+3+3
P.Value <- 1-pchisq(q = LMw, df = Gl)
Vc <- qchisq(p = 0.95, df = Gl)
Salida_Whitw <- c(LMw, Vc, P.Value)
names(Salida_Whitw) <- c("LMw", "Valor Critico", "P Value")
stargazer(Salida_Whitw, title = "Resultado de la prueba de White", type = "text", digits = 5)
##
## Resultado de la prueba de White
## ==============================
## LMw Valor Critico P Value
## ------------------------------
## 33.73166 16.91898 0.00010
## ------------------------------
#Use la libreria lmtest para verificar si su varianza residual es homocedástica a través de la prueba de White (incluya los términos cruzados).
library(lmtest)
## Loading required package: zoo
##
## Attaching package: 'zoo'
## The following objects are masked from 'package:base':
##
## as.Date, as.Date.numeric
options(scipen = 999999)
Prueba_White <- bptest(ModeloHeterocedasticidad, ~I(lotsize^2) + I(sqrft^2) + I(bdrms^2) + lotsize*sqrft+lotsize*bdrms+ sqrft*bdrms, data = hprice1)
print(Prueba_White)
##
## studentized Breusch-Pagan test
##
## data: ModeloHeterocedasticidad
## BP = 33.732, df = 9, p-value = 0.00009953
#Presente sus resultados de forma gráfica a través de la librería fastGraph
library(fastGraph)
PW <- Prueba_White$statistic
gl <- Prueba_White$parameter
VC <- qchisq(p = 0.05, df = gl,lower.tail = FALSE)
shadeDist(PW, ddist = "dchisq",
parm1 = gl,
lower.tail = FALSE, xmin = 0,
sub= paste("VC:", round(VC, digits = 3)," "," ",
"LMw:", round(PW,digits = 3)),
main = "Prueba White")