The Importance of Industry Classification in Estimating Concentration Ratios
Economics Letters, Vol. 114, No. 2, pp. 224-227, 2012
Posted: 25 Nov 2011 Last revised: 20 Sep 2012
Date Written: November 25, 2011
We compare different industry concentration ratios based on the Standard Industry Classification (SIC) system to ratios based on the Global Industry Classification Standard (GICS) system and demonstrate through the analysis of industry markups that GICS-based measures are better proxies for the actual industry concentration than SIC-based measures.
Keywords: Concentration Indices, Industry markup, SIC, GICS, Classification
JEL Classification: D4, C8
Suggested Citation: Suggested Citation