PORTFOLIO ENTRY

Jostling for Advantage: Licensing and Entry into Patent Portfolio Races

Licensing in a patent thicket allows firms to either avoid or resolve hold-up. Firms’ R&D incentives depend on whether they license ex ante or ex post. We develop a model of a patent portfolio race, which allows for endogenous R&D efforts, to study firms’ choice between ex ante and ex post licensing. The model shows that firms’ relationships in product markets and technology space jointly deter...

Ambulatory Computerized Provider Order Entry (CPOE): Findings from the AHRQ Health IT Portfolio

Entry Entry Entry

A new kind of data model has recently emerged in which the database is not constrained by a conventional schema. Systems like ACeDB, which has become very popular with biologists, and the recent Tsimmis proposal for data integration organize data in tree-like structures whose components can be used equally well to represent sets and tuples. Such structures allow great exibility in data represen...

Modern Portfolio Theory, Digital Portfolio Theory and Intertemporal Portfolio Choice

The paper compares three portfolio optimization models. Modern portfolio theory (MPT) is a short-horizon volatility model. The relevant time horizon is the sampling interval. MPT is myopic and implies that investors are not concerned with long-term variance or mean-reversion. Intertemporal portfolio choice is a multiple period model that revises portfolios continuously in response to relevant s...

Cover’s Universal Portfolio, Stochastic Portfolio Theory and the Numéraire Portfolio

Cover’s celebrated theorem states that the long run yield of a properly chosen “universal” portfolio is as good as the long run yield of the best retrospectively chosen constant rebalanced portfolio. The “universality” pertains to the fact that this result is model-free, i.e., not dependent on an underlying stochastic process. We extend Cover’s theorem to the setting of stochastic portfolio the...