M39 XuanLong Nguyen, Martin Wainwright and Michael Jordan Estimating divergence functionals and the likeliho o d ratio by p enalized convex risk minimization ˇ given n resp. m i.i.d. samples: X1 , . . . Xn Y1 , . . . Ym P (unknown) Q (unknown) ˇ propose, analyze and evaluate convergence behavior of a nonparametric estimator for divergence functional D (P, Q) based on (X, Y ): D (P, Q) := d Q dP d P= q 0 p0 dP dQ p 0 dľ. ­ also estimator of likelihood ratio function ˇ applications: estimating mutual information and KL divergence in coding, independent component analysis, dimensionality reduction, experiment design,... ˇ idea: based on variational characterization of divergence functionals