Marcel Timmer

University of Groningen
9700 AB Groningen
The Netherlands


NBER Working Papers and Publications

February 2018Using Online Prices for Measuring Real Consumption Across Countries
with Alberto Cavallo, W. Erwin Diewert, Robert C. Feenstra, Robert Inklaar: w24292
We show that online prices can be used to construct quarterly purchasing power parities (PPPs) with a closely-matched set of goods and identical methodologies in a variety of developed and developing countries. Our results are close to those reported by the International Comparisons Program (ICP) in 2011 and the OECD in 2014, and can be used to obtain more up-to-date estimates of real consumption across countries without the need for consumer price index extrapolations. We discuss advantages and limitations associated with the use of online prices for PPs, including issues of representativeness and limited coverage of product categories and countries.
July 2013The Next Generation of the Penn World Table
with Robert C. Feenstra, Robert Inklaar: 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...

Published: Feenstra, Robert C., Robert Inklaar, and Marcel P. Timmer. 2015. "The Next Generation of the Penn World Table." American Economic Review, 105(10): 3150-82. citation courtesy of

January 1999Prices, Quantities, and Productivity in Industry: A Study of Transition Economies in a Comparative Perspective
with Bart van Ark, Erik Monnikhof
in International and Interarea Comparisons of Income, Output, and Prices, Alan Heston and Robert E. Lipsey, editors
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