Abstract Quantifier elimination (qelim) is used in many automated reasoning tasks including program synthesis, exist-forall solving, quantified SMT, Model Checking, and solving Constrained Horn Clauses (CHCs). Exact qelim computationally expensive. Hence, it often approximated. For example, Z3 uses “light” pre-processing to reduce the number of variables. CHC-solver Spacer model-based projectio...

Abstract We show that every isometric action on a Cantor set is conjugate to an inverse limit of actions finite sets; and faithful by finitely generated amenable group residually finite.

This paper studies the identification and estimation of optimal linear approximation a structural regression function. The parameter in is called Optimal Linear Instrumental Variables Approximation (OLIVA). shows that necessary condition for standard inference on OLIVA also sufficient existence an IV estimand model. instrument unknown may not be identified. A Two-Step (TSIV) estimator based Tik...

We construct a Goodwillie tower of categories which interpolates between the category pointed spaces and spectra. This refines identity functor in precise sense. More generally, we such for large class ∞ <...