#load library
library(gmnl)

#read in data
ennis_ss <- read.table("C:\\Users\\decar\\Desktop\\Choice\\Ennis_3AFC\\ennis_choice_SS.txt", header=TRUE)
colnames(ennis_ss)[1]<-"id"

#Take a look at the variables
head(ennis_ss)

#Transform to form needed by gmnl using mlogit.data
library(mlogit)
tr <- mlogit.data(ennis_ss, choice="ch", shape="long",
                  alt.levels = c(1,2,3), id.var="id")
head(tr)

# multinomial logit in gmnl
model <- gmnl(ch ~ 0 + salt + x1 + x2, data= tr)
summary(model)

# multinomial probit in mlogit package
model1 <- mlogit(ch ~ salt, data=tr,reflevel=3,probit=T)
summary(model1)

# multinomial probit in MNP
# read in data
ennis1_ss <- read.table("C:\\Users\\decar\\Desktop\\Choice\\Ennis_3AFC\\ennis_choice_ss_mnp.txt", header=TRUE)
colnames(ennis1_ss)[1]<-"trial"
#Take a look at the variables
head(ennis1_ss)

library(MNP)
model <- mnp(choice ~ 1, data=ennis1_ss, choiceX = list(a=x1, b=x2, c=x3), base = 'c',
             cXnames = "salt", burnin=4000, thin=3, n.draws=20000, verbose=TRUE)
summary(model)