Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Global Value Chains have proliferated in economic policy debates. Yet a key concept—trade in value added—is likely mismeasured because of sectoral aggregation bias stemming from reliance on input-output tables. This paper uses comprehensive firm-level data on domestic and international transactions to study this bias. We find that sectoral aggregation leads to overstated trade in value added. The magnitude of the bias varies across countries—at 2–5 p.p. of gross exports for Belgium and 17 p.p. for China. We study how the interplay between within-sector heterogeneities in firms' import and export intensities and size determine the magnitude of the bias.