We provide a tractable characterization of the sharp identification region of the parameters ø in a broad class of incomplete econometric models. Models in this class have set valued predictions that yield a convex set of conditional or unconditional moments for the observable model variables....

The employment of capital is rival in nature. Small countries do not benefit from taxing its employment. By contrast, the use of digital services is non-rival and small countries do benefit from taxing expenditures on such services. In fact, some countries have already decided to tax digital...