NBER Working Papers by Robert Inklaar

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Working Papers

July 2013The Next Generation of the Penn World Table
with Robert C. Feenstra, Marcel Timmer: w19255
We describe the theory and practice of real GDP comparisons across countries and over time. Effective with version 8, the Penn World Table (PWT) will be taken over by the University of California, Davis and the University of Groningen, with continued input from Alan Heston at the University of Pennsylvania. Version 8 will expand on previous versions of PWT in three respects. First, it will distinguish real GDP on the expenditure side from real GDP on the output side, which differ by the terms of trade faced by countries. Second, it will distinguish growth rates of GDP based on national accounts data from growth rates that are benchmarked in multiple years to cross-country price data. Third, data on capital stocks will be reintroduced. Some illustrative results from PWT version 8 are discus...
December 2008The Value of Risk: Measuring the Service Output of U.S. Commercial Banks
with Susanto Basu, J. Christina Wang: w14615
Rather than charging direct fees, banks often charge implicitly for their services via interest spreads. As a result, much of bank output has to be estimated indirectly. In contrast to current statistical practice, dynamic optimizing models of banks argue that compensation for bearing systematic risk is not part of bank output. We apply these models and find that between 1997 and 2007, in the U.S. National Accounts, on average, bank output is overestimated by 21 percent and GDP is overestimated by 0.3 percent. Moreover, compared with current methods, our new estimates imply more plausible estimates of the share of capital in income and the return on fixed capital.
January 2007International Comparisons of R&D Expenditure: Does an R&D PPP Make a Difference?
with Sean M. Dougherty, Robert H. McGuckin, Bart van Ark: w12829
Purchasing power parities (PPPs) for R&D expenditure in 19 manufacturing industries are developed for France, Germany, Japan, the Netherlands and the United Kingdom relative to the United States for the years 1997 and 1987. These PPPs are based on R&D input prices for specific cost categories and differ substantially from current practice of comparing R&D expenditure using GDP PPPs and deflators. After taking into account differences in the relative price of R&D labor and materials, separate PPPs for other R&D cost categories are less essential, and a simpler version using GDP PPPs for these other categories should suffice. Our preferred PPPs are used to compare international R&D costs and intensity. The results suggest that the efforts devoted to R&D in each country are more similar acros...

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