This paper proposes a parsimoniously time varying parameter vector autoregressive model (with exogenous variables, VARX) and studies the properties of the Lasso and adaptive Lasso as estimators of this model. The parameters of the model are assumed to follow parsimonious random walks, where...

In this paper the well-known minimax theorems of Wald, Ville and Von Neumann are generalized under weaker topological conditions on the payoff function f and/or extended to the larger set of the Borel probability measures instead of the set of mixed strategies.