We study the complexity of computing Boolean functions using AND, OR
and NOT gates. We show that a circuit of depth $d$ with $S$ gates can
be made to output a constant by setting $O(S^{1-\epsilon(d)})$ (where
$\epsilon(d) = 4^{-d}$) of its input values. This implies a
superlinear size lower bound ... more >>>

We study the complexity of proving the Pigeon Hole
Principle (PHP) in a monotone variant of the Gentzen Calculus, also
known as Geometric Logic. We show that the standard encoding
of the PHP as a monotone sequent admits quasipolynomial-size proofs
in this system. This result is a consequence of ... more >>>

We study an extension of active learning in which the learning algorithm may ask the annotator to compare the distances of two examples from the boundary of their label-class. For example, in a recommendation system application (say for restaurants), the annotator may be asked whether she liked or disliked a ... more >>>