title: coxph Error weights must be finite. How do I return this model?
body: <p>I have run a cox regression model below</p>
  <pre><code>allcause_cox&lt;-coxph(Surv(allcause_time, allcause)~centgroup, data=fulldata)
  </code></pre>
  <p>This has run fine. However I want to return robust standard error. Therefore I have introduced the</p>
  <pre><code>cluster(parity)
  </code></pre>
  <p>term into the model, where parity is another variable in my data set. However this won't run. It returns the error</p>
  <pre><code>&gt; allcause_cox&lt;-coxph(Surv(allcause_time, allcause)~centgroup, data=fulldata, cluster(parity))
  
  Error in coxph(Surv(allcause_time, allcause)~centgroup, data=fulldata, :
     weights must be finite
  </code></pre>
  <p>Is there a solution to this? I have read about the weight term which can be added but I'm not sure what this does.</p>