In [1]:
# rm(list=ls())
options(OutDec = ",") 
#==============================================================================
# Exemplo:
#
# Aproximacao assintotica pela Normal
#
#==============================================================================
# Amostra n=1 e y=3.
#==============================================================================
y       <- 3
a       <- 3             # Hiperparametros (priori)
b       <- 3             # Hiperparametros (priori)
x       <- seq(-2,6,0.01) 
lambda1 <- dgamma(x,a+y,b+1)
media1  <- (a+y-1)/(b+1)
var1    <- media1/(b+1)
lambda2 <- dnorm(x,media1,sqrt(var1))
In [2]:
#==============================================================================
# Grafico para comparacao
#==============================================================================
par(mfrow=c(1,1),lwd=2.0,cex.lab=1.5,cex.axis=1.5,
    lab=c(10,6,5),mar=c(4.5,5,1,1),xpd=T,cex.main=2.0,bty="n")
plot(x,lambda1,type="l",lwd=4,col="black",xlab=expression(lambda),
  ylab=expression(paste("f(",lambda,"|y)",sep=" ")),ylim=c(0,0.8))
lines(x,lambda2,lwd=4,col="red",lty=2)
legend("topright",legend=c("Verdadeira","Aproximada"),
  col=c("black","red"),lty=c(1,2),lwd=c(4,4),bty="n",cex=1.5)
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In [3]:
# rm(list=ls()) 
#==============================================================================
# graphics.off()
#==============================================================================
# Fim
#==============================================================================