What do we know about cosmography

  title={What do we know about cosmography},
  author={Ming Zhang and Hong Li and Junqing Xia},
  journal={The European Physical Journal C},
In the present paper, we investigate the cosmographic problem using the bias–variance trade-off. We find that both the z-redshift and the $$y=z/(1+z)$$y=z/(1+z)-redshift can present a small bias estimation. It means that the cosmography can describe the supernova data more accurately. Minimizing risk, it suggests that cosmography up to the second order is the best approximation. Forecasting the constraint from future measurements, we find that future supernova and redshift drift can… 
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