The contribution of this paper is three-fold. Firstly, a characterisation theorem of the sub-hypotheses comprising the seasonal unit root hypothesis is presented which provides a precise formulation of the alternative hypotheses against which regression-based seasonal unit root tests test....

Applied studies on the relationship between geography and technological innovation for United States, Germany, France and Italy have shown the positive effects that academic research exerts on the innovative output of firms at a spatial level. The purpose of this paper is to look for new...