title: Error: "could not find function "lengths"
body: <p>While running:</p>
  
  <pre><code> reg_model = glmer(modeling1 ~ pTOT_VIOPT_CT + (1|STUDY_CODE_ALIAS),
                    data=data_CACZ, family=binomial)
  </code></pre>
  
  <p>I am getting the error:</p>
  
  <pre><code>Error in .fixupDimnames(.Object@Dimnames) : 
    could not find function "lengths"
  </code></pre>
  
  <p>Not sure what could be the possible reason.</p>
  
  <p>FYI: I am putting below the <code>sessionInfo()</code>:</p>
  
  <pre><code>R version 3.0.2 (2013-09-25)
  Platform: i386-w64-mingw32/i386 (32-bit)
  
  locale:
  [1] LC_COLLATE=English_United States.1252  LC_CTYPE=English_United States.1252    LC_MONETARY=English_United States.1252
  [4] LC_NUMERIC=C                           LC_TIME=English_United States.1252    
  
  attached base packages:
  [1] stats     graphics  grDevices utils     datasets  methods   base     
  
  other attached packages:
  [1] Rcpp_0.11.5  lme4_1.1-10  Matrix_1.2-3 car_2.0-21   MASS_7.3-29 
  
  loaded via a namespace (and not attached):
  [1] grid_3.0.2      lattice_0.20-29 minqa_1.2.4     nlme_3.1-118    nloptr_1.0.4    nnet_7.3-7      splines_3.0.2   tools_3.0.2   
  </code></pre>