code: def anova_ols(y, x):
      X = add_constant(data2dummy(x), prepend=False)
      res = OLS(y, X).fit()
      return (
          res.fvalue,
          res.f_pvalue,
          res.rsquared,
          np.sqrt(res.mse_resid),
      )
  
file_path: statsmodels/statsmodels/sandbox/regression/anova_nistcertified.py
imports: from statsmodels.compat.python import lmap
  import os
  import numpy
  from scipy import stats
  from statsmodels.tools.tools import add_constant
  from statsmodels.regression.linear_model import OLS
  from .try_ols_anova import data2dummy
label_desc: Use image node_id 3 for calling a global function with example usage: anova_ols(y, x) and returns: res,  res,  res,  np