Fluctuation Analysis of the Non-abelian Born-Infeld Action in Background Intersecting D-branes

{We carry out a fluctuation analysis of the non-abelian Born-Infeld action up to order F^6 in the presence of a background intersecting D-branes system. We compare the mass spectrum which is obtained in our analysis to the spectrum derived from the worldsheet analysis. The mass spectra completely agree with each other. This result provides a strong support for the claim that the action we analyze here, which was proposed in hep-th/0208044 by Koerber and Sevrin, is the correct low energy effective action of string theory.Comment: 16 pages, PTP style. reference added, minor correction

R&D and Market Value: Appropriability vs. Preemption

The recent empirical studies on innovation and market value suggest that R&D has a strong complementarity with market share in the market valuation of firms. Blundell, Griffith and Reenen (1999) argue that it represents the strategic preemptive effect, while Hall and Vopel (1997) suggest a Schumpeterian reason (the cost of financing R&D is lower for large firms). The theoretical framework of these studies is the classical work by Griliches (1981), which postulates that the market value of firm is given by the sum of the values of physical capital and R&D capital with respective multipliers. However, non-rivalry in using new knowledge within a firm makes this framework highly questionable. This paper examines the nexus between R&D and market value, based on a simple but new structural model. Major findings are the following. First, the new model shows that the market evaluation of R&D may well be high for a firm with a large market share, simply due to its appropriability advantage. Second, our estimation based on the data of the Japanese firms shows that the new specification performs better. Third, it shows that there is no statistical support for the prevalence of preemption effect.R&D, market value, appropriability, preemption

Determinants of R&D and Its Productivity: Identifying Demand and Supply Channels (First revision)

Identifying whether an exogenous factor affects R&D from a demand side or from a supply side is an important issue. This paper, first, theoretically shows that a favorable change in either side can reduce the R&D productivity in equilibrium, so that the reduced form estimation cannot provide a clear identification. Secondly, it estimates both structural and reduced form patent production functions, based on instrumental variables approach, using a large database on Japanese firms. According to the estimation, while the initial firm size, market concentration or export orientation increases R&D, none of them significantly shifts the structural patent production function.R&D productivity, patent, firm size, competition

Determinants of high-royalty contracts and the impact of stronger protection of intellectual property rights in Japan

This paper first reviews how Japan has strengthened the protection of intellectual property rights (IPRs), focusing on the expansion of the patentable subject matter, the restriction of the possibility of compulsory licensing, stronger deterrence against infringement and the introduction of the doctrine of equivalents. Second, based on the statistical analysis of sector-level panel data, it shows that (1)R&D intensity of domestic industry, trademark licensing, cross-licensing and, to a smaller degree, monopoly provisions are the significant determinants of the incidence of high-royalty contracts, and (2)Stronger protection of intellectual property rights looks to have increased the incidence of high-royalty contracts in the latter part of 1990s in the Japanese industries for which patent is important for appropriability.Intellectual property rights, Licensing contract, Appropriability, Patent

General formulas for capacity of classical-quantum channels

The capacity of a classical-quantum channel (or in other words the classical capacity of a quantum channel) is considered in the most general setting, where no structural assumptions such as the stationary memoryless property are made on a channel. A capacity formula as well as a characterization of the strong converse property is given just in parallel with the corresponding classical results of Verd\'{u}-Han which are based on the so-called information-spectrum method. The general results are applied to the stationary memoryless case with or without cost constraint on inputs, whereby a deep relation between the channel coding theory and the hypothesis testing for two quantum states is elucidated. no structural assumptions such as the stationary memoryless property are made on a channel. A capacity formula as well as a characterization of the strong converse property is given just in parallel with the corresponding classical results of Verdu-Han which are based on the so-called information-spectrum method. The general results are applied to the stationary memoryless case with or without cost constraint on inputs, whereby a deep relation between the channel coding theory and the hypothesis testing for two quantum states is elucidated