#Script du modèle - 2 covariables

model{
# Y= teneur en protéines du blé
# INN_cr = Indice de nutrition azotée centré réduit   # SPAD_cr = Mesure de transmittance centrée réduite
# alpha=paramètres de la régression   # prec=paramètre de précision = 1/variance 
# m_INN, s_INN , m_SPAD, s_SPAD = moyennes et écarts-type empiriques de INN et SPAD

for (i in 1:N) {         
	Y[i] ~ dnorm(mu[i],prec)       
         mu[i]<-alpha[1]+alpha[2]*SPAD_cr[i]+alpha[3]*INN_cr[i]
	loglik[i] <- -0.5*log(2*pi)+0.5*log(prec)-0.5*prec*pow(Y[i]-mu[i],2) 

} 
alpha_nonc[1]<- alpha[1]-alpha[2]*(m_SPAD/s_SPAD)-alpha[3]*(m_INN/s_INN)
alpha_nonc[2]<- alpha[2]/s_SPAD
alpha_nonc[3]<- alpha[3]/s_INN

for (j in 1:3) {          
	alpha[j]~dnorm(0.0,1.0E-6)   
}
sd  ~ dunif(0,100)   
prec<- 1/pow(sd,2)
}


#Données 
list(Y=c(1.19000E+01, 1.03000E+01, 1.24000E+01, 1.21000E+01, 1.24000E+01, 1.27000E+01, 1.15000E+01, 1.36000E+01, 9.90000E+00, 1.11000E+01, 1.06000E+01, 1.20000E+01, 1.28000E+01, 1.16000E+01, 1.12000E+01, 1.03000E+01, 1.29000E+01, 1.03000E+01, 1.15000E+01, 1.41000E+01, 1.26000E+01, 1.27000E+01, 1.19000E+01, 9.20000E+00, 1.25000E+01, 1.19000E+01, 1.13000E+01, 1.10000E+01, 1.00000E+01, 1.59000E+01, 1.06000E+01, 1.16000E+01, 1.14000E+01, 1.09000E+01, 1.46000E+01, 1.07000E+01, 9.40000E+00, 1.30000E+01, 1.25000E+01, 1.29000E+01, 1.11000E+01, 1.29000E+01, 1.32000E+01), SPAD_cr=c(-1.82756E-02, -7.44061E-01, 5.57348E-01, 7.57564E-01, 6.57456E-01, 8.07619E-01, 8.32646E-01, 1.08292E+00, 7.57564E-01, -1.68438E-01, 1.15800E+00, 1.31887E-01, 1.50838E+00, 1.33319E+00, -1.29466E+00, 5.07293E-01, 1.08292E+00, -2.09552E+00, -1.75946E-01, 6.07402E-01, 1.14368E-01, 5.68057E-02, 3.24596E-01, -1.72763E+00, -7.26542E-01, -3.36120E-01, -1.47736E+00, -1.54493E+00, -1.53742E+00, -2.10984E-01, -1.82773E+00, -2.43519E-01, -1.82756E-02, 1.31887E-01, -1.89531E+00, -4.93790E-01, -5.18818E-01, -3.93682E-01, 1.08292E+00, 1.35821E+00, 8.07619E-01, 7.82591E-01, 1.00784E+00), INN_cr=c(1.26709E+00, -2.61237E-01, -2.61237E-01, 1.26709E+00, -1.02540E+00, 5.02926E-01, 1.26709E+00, 5.02926E-01, -1.78956E+00, -1.02540E+00, -1.02540E+00, -1.02540E+00, 5.02926E-01, -2.61237E-01, -2.61237E-01, -1.78956E+00, 5.02926E-01, -1.10182E+00, -8.72567E-01, 2.03125E+00, 1.03784E+00, 1.11426E+00, 2.73677E-01, -1.63673E+00, -7.96151E-01, 1.95483E+00, -5.66902E-01, 1.97261E-01, -6.43318E-01, 1.49634E+00, -6.43318E-01, 1.97261E-01, -1.08404E-01, -4.90486E-01, 3.50093E-01, 4.44281E-02, -8.72567E-01, -1.84821E-01, -7.19735E-01, 8.08591E-01, -4.14069E-01, 6.55758E-01, 1.80200E+00), N=4.30000E+01, m_INN=8.34186E-01, s_INN=1.30862E-01, m_SPAD=4.55730E+01, s_SPAD=3.99567E+00, pi=3.14159E+00)


#Initialisation des chaînes
#Chaîne 1
list(alpha=c(0,0,0),sd=1)
#Chaîne 2
list(alpha = c(5,5,5),sd = 0.1)
#Chaîne 3
list(alpha = c(-5,-5,-5),sd = 10)