  We construct a simple, regularized estimator for the dark energy equation of
state by using the recently introduced linear response approximation. We show
that even a simple regularization substantially improves the performance of the
free form fitting approach. The use of linear response approximation allows an
analytic construction of maximum likelihood estimator, in a convenient and easy
to use matrix form. We show that in principle, such regularized free form
fitting can give us an unbiased estimate of the functional form of the equation
of state of dark energy. We show the efficacy of this approach on a simulated
SNAP class data, but it is easy to generalize this method to include other
cosmological tests. We provide a possible explanation for the sweet spots seen
in other reconstruction methods.
