title: GLMM Convergence issues with lme4
body: <p>I am modelling the number of jobs over month 1-112 (taken over ~10 years) for each Hospital. The number of jobs over time vary depending on the hospital so I have defined the following multilevel model as a starting point:</p>
  
  <pre><code>glmer.nb(Jobs ~ 1 + Region + Month + ( Month | factor(Region)),
                       data = df_month_region, 
                       family = poisson(link = "log"))
  </code></pre>
  
  <p>My data looks very similar to this:</p>
  
  <pre><code>df &lt;- data.frame(
    Region = rep(1:14, each=112),
    Month = rep(seq(1,112,1),14),
    Job = rpois(112*14, 0.7)
  )
  </code></pre>
  
  <p>I would like to know:</p>
  
  <p>1) Does modelling my data in this format makes sense? Would it make more sense to have a column for year and month separately?</p>
  
  <p>2) How do I overcome this error: "Model failed to converge with max|grad| = 0.00361688 (tol = 0.001, component 1)Model is nearly unidentifiable: very large eigenvalue"? - I have followed the steps here: <a href="https://rstudio-pubs-static.s3.amazonaws.com/33653_57fc7b8e5d484c909b615d8633c01d51.html" rel="nofollow noreferrer">https://rstudio-pubs-static.s3.amazonaws.com/33653_57fc7b8e5d484c909b615d8633c01d51.html</a> as commonly recommended on this site but I am starting to think the underlying problem lies perhaps with how I have setup my dataframe or my model?</p>