# Error when do categorical

**URL:** <https://discourse.mc-stan.org/t/error-when-do-categorical/22914>\
**Category:** General\
**Tags:** rstan\
**Created:** [June 8, 2021, 1:40pm UTC](https://discourse.mc-stan.org/t/error-when-do-categorical/22914 "2021-06-08T13:40:15Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![WTnicole\_WTnicole](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.mc-stan.org/wtnicole_wtnicole/32/11698_2.png) [@WTnicole\_WTnicole](https://discourse.mc-stan.org/u/WTnicole_WTnicole)\
**Post date:** [June 8, 2021, 1:40pm UTC](https://discourse.mc-stan.org/t/error-when-do-categorical/22914/1 "2021-06-08T13:40:16Z")

</div>

It always shows that no matches for : available argument signatures fir categorical: real return type required for probability function.

```

data {
  int<lower=0> N;
  int<lower=0> N1;
  int<lower=0> P;
  int<lower=0> p1;
  int<lower=0> p2;
  int<lower=0> p3;
  int<lower=0> cat1;
  int<lower=2>cat2[p3];
  real Y[N];
  int X[N]; 
  matrix[N,P] M1;
  int M2[N,P]; 
  int Mc[N,P];
  int contm[p1];
  int binm[p2];
  vector[p3] cat3;
  
}
parameters {
        
  real alpha0[p1];
  real alpha1[p1];
  real alpha0_b[p2];
  real alpha1_b[p2];
  matrix[p3,cat2[p3]] alpha0_c;
  matrix[cat1,cat2[p3]] alpha1_c;
   
  
  real beta0;
  vector[P] beta;
  real c;
  real<lower=0> sigma1[p1];
  real<lower=0> sigma2;

}

model {
   matrix[N,p1] mu_M1;
   matrix[N,p2] mu_M1_b;
   real mu_Mc[N,p3,N1];
   matrix[N,cat1] sum_Mc;
   vector[N] mu_Y;
   real mu_Mc00[N,cat1,cat2[p3]];
   
   for (i in 1:N){
     
    mu_Y[i]= beta0 + c*X[i] + dot_product(beta,M1[i,]);
    Y[i] ~ normal(mu_Y[i],sigma2);
       for (j in 1:p1){
         
    mu_M1[i,j]=alpha0[j]+alpha1[j]*X[i];
    M1[i,contm[j]] ~ normal(mu_M1[i,j],sigma1[j]);
} 
    
       for (k in 1:p2){
         
     mu_M1_b[i,k] = alpha0_b[k]+alpha1_b[k]*X[i];
     M2[i,binm[k]]~bernoulli_logit(mu_M1_b[i,k]);
} 
     
     for (j in 1:cat1){
     mu_Mc[i,j,1] =1; 
     for (k in 2:cat2[j]){
     mu_Mc[i,j,k] =exp(alpha0_c[j,k-1]+alpha1_c[j,k-1]*X[i]);
      }
      sum_Mc[i,j]=sum(mu_Mc[i,j,1:cat2[j]]);
      for (l in 1:cat2[j])
      {mu_Mc00[i,j,l] =mu_Mc[i,j,l]/sum_Mc[i,j];}
      Mc[i,j]~categorical(mu_Mc00[i,j,1:cat2[j]]);
   }
     

}
    

```

---

<div class="post-metadata">

**Author:** ![andrjohns](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.mc-stan.org/andrjohns/32/15297_2.png) [@andrjohns](https://discourse.mc-stan.org/u/andrjohns)\
**Post date:** [June 8, 2021, 1:47pm UTC](https://discourse.mc-stan.org/t/error-when-do-categorical/22914/2 "2021-06-08T13:47:03Z")

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Please don’t open multiple threads for the same topic