author={Varun Sahni and Alexei A. Starobinsky},
  journal={International Journal of Modern Physics D},
This review summarizes recent attempts to reconstruct the expansion history of the universe and to probe the nature of dark energy. Reconstruction methods can be broadly classified into parametric and non-parametric approaches. It is encouraging that, even with the limited observational data currently available, different approaches give consistent results for the reconstruction of the Hubble parameter H(z) and the effective equation of state w(z) of dark energy. Model independent… 

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