title: Discrepencies in Brier scores using pec and crps function in R
body: <p>I'm using two ways to compute Brier Scores. Should be the same but I get different stuffs.<br />
  Is  Brier score from Pec different from Integrated Brier score obtained with crps function.</p>
  <pre><code>model.list &lt;- list(
      fit.coxph.A = fit.coxph.Acat,
      fit.coxph.B = fit.coxph.Bcat
  )
  
  pec &lt;- pec(
  model.list,  Surv(Diff.days, Death.binary) ~ 1, # formula for IPCW
    data = dataset.merged.1, # new data not used for model fit
    times = times,
    exact = FALSE
  )
  summary(pec)
  
  
  
   AppErr 
           time n.risk Reference fit.coxph.A fit.coxph.B
      1   0.000     52     0.000       0.000       0.000
      2 182.625     37     0.199       0.195       0.175
      3 365.250     26     0.248       0.227       0.194
      4 547.875     23     0.250       0.213       0.182
      5 730.500     20     0.248       0.206       0.184
  </code></pre>
  <p>crps(pec, times = times)</p>
  <pre><code>Integrated Brier score (crps):
  
              IBS[0;time=182.6) IBS[0;time=365.2) IBS[0;time=547.9)
  Reference                   0             0.099             0.149
  fit.coxph.A                 0             0.098             0.141
  fit.coxph.B                 0             0.087             0.123
              IBS[0;time=730.5)
  Reference               0.174
  fit.coxph.A             0.159
  fit.coxph.B             0.138
  </code></pre>