glm_lpmf</code></strong><code>(int[] y | matrix x, real alpha, vector beta)</code><br>The log Poisson probability mass of <code>y</code> given the log-rate <code>alpha + x * beta</code>, where the same intercept <code>alpha</code> is used for all observations. The number of rows of the independent variable matrix <code>x</code> needs to match the size of the dependent variable vector <code>y</code> and the number of columns of <code>x</code> needs to match the size of the coefficient vector <code>beta</code