r weights for weights in a cox how to model speedup how to speed up weighted regressions in r r regress using weights weight models r how to speed up weights in r how to speed up r formulas weighted model in r how to speedup models in r weights definition in r weighted model speedup what is the r weighting how to speed up weights in r what is the function weights in r how to speed up weights in r why do you need weighted r how to speed up weights weights in r model speed up can you regress a data set using weights weight model r