Rietveld/Profile fit R factors. Note that the R factor computed for Rietveld refinements using the extracted reflection intensity values (often called the Rietveld or Bragg R factor, R_B) is not properly a profile R factor. pdbx_pd_proc_ls_prof_wR_factor often called R_wp, is a weighted fitness metric for the agreement between the observed and computed diffraction patterns R_wp = SQRT { sum_i ( w(i) [ I_obs(i) - I_calc(i) ]² ) / sum_i ( w(i) [I_obs(i)]² ) } Note that in the above equations, w(i) is the weight for the ith data point I_obs(i) is the observed intensity for the ith data point, sometimes referred to as y_i(obs) or y_oi. I_calc(i) is the computed intensity for the ith data point with background and other corrections applied to match the scale of the observed dataset, sometimes referred to as y_i(calc) or y_ci. n is the total number of data points (see _refine.pdbx_pd_number_of_points) less the number of data points excluded from the refinement. p is the total number of refined parameters.