% COMANDOS EM R REFERENTES AO EXEMPLO DE SNACKS

 snacks = read.table("snacks.txt", header=TRUE)
 attach(snacks)

 grupo = factor(grupo)

 boxplot(split(textura, grupo), xlab="Grupo", ylab="Textura")
 boxplot(split(textura, semana), xlab="Semanas", ylab="Textura")

 require(robustbase)
 adjbox(split(textura, grupo), xlab="Grupo", ylab="Textura")
 adjbox(split(textura, semana), xlab="Semanas", ylab="Textura")

 s1 = semana
 s2 = s1*s1
 
 require(dglm)
 require(statmod)

 fit1.snacks = dglm(textura ~ grupo + s1 + s2, ~ grupo, family=Gamma(link=log))

 summary(fit1.snacks)

 fit2.snacks = dglm(textura ~ grupo + s1 + s2, ~ grupo, family=Gamma(link=log), method="reml")
 
 summary(ajuste3.snacks)

 fit.model = ajuste2.snacks

 source("diag_gama_dglm")
 source("diag_gama_dglm_disp")

 source("envel_gama_dglm_snacks") 
 source("envel_gama_dglm_disp_snacks") 

 require(gamlss)
 fit3.snacks = gamlss(textura ~ grupo + s1 + s2, ~ grupo, family=GA)

 summary(fit3.snacks)
 plot(fit3.snacks)
 wp(fit3.snacks)

 term.plot(fit3.snacks, what ="mu", terms=1)
 term.plot(fit3.snacks, what ="mu", terms=2)
 term.plot(fit3.snacks, what ="sigma", terms=1)