docstr: Return linear predicted values from a design matrix.
  
  Parameters
  ----------
  params : array_like
      Parameters of a linear model
  exog : array_like, optional.
      Design / exogenous data. Model exog is used if None.
  
  Returns
  -------
  An array of fitted values
code: def predict(self, params, exog=None):
      """
      Return linear predicted values from a design matrix.
  
      Parameters
      ----------
      params : array_like
          Parameters of a linear model
      exog : array_like, optional.
          Design / exogenous data. Model exog is used if None.
  
      Returns
      -------
      An array of fitted values
      """
      # copied from linear_model  # TODO: then is it needed?
      if exog is None:
          exog = self.exog
      return np.dot(exog, params)
  
imports: import numpy
  import scipy.stats
  import statsmodels.base.model
  import statsmodels.base.wrapper
  import statsmodels.regression._tools
  import statsmodels.regression.linear_model
  import statsmodels.robust.norms
  import statsmodels.robust.scale
  from statsmodels.tools.decorators import cache_readonly
  from statsmodels.tools.sm_exceptions import ConvergenceWarning
label_desc: Use image node_id 5 for calling the RLM obj's underlying member method code with example usage: obj.predict(params, exog) and returns: np