Excess Comovement of Stock Returns: Evidence from Cross-Sectional Variation in Nikkei 225 Weights

Robin Greenwood

The Review of Financial Studies, 2008, vol. 21, issue 3, 1153-1186

Abstract: Relative to their weights in a value-weighted index, a number of stocks in Japan's Nikkei 225 stock index are overweighted by a factor of 10 or more. I document a strong positive relation between overweighting and the comovement of a stock with other stocks in the Nikkei index, and a negative relationship between index overweighting and comovement with stocks outside of the index. The cross-sectional approach resolves endogeneity problems associated with event study demonstrations of excess comovement. A trading strategy that bets on the reversion of stock prices of overweighted stocks generates economic profits, confirming that the observed comovement patterns are excessive, and providing further evidence that comovement of stock returns can be a consequence of commonality in trading behavior. The Author 2007. Published by Oxford University Press on behalf of The Society for Financial Studies., Oxford University Press.

Date: 2008
References: Add references at CitEc
Citations: View citations in EconPapers (63)

Downloads: (external link)
http://hdl.handle.net/10.1093/rfs/hhm052 (application/pdf)
Access to full text is restricted to subscribers.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:oup:rfinst:v:21:y:2008:i:3:p:1153-1186

Ordering information: This journal article can be ordered from
https://academic.oup.com/journals

Access Statistics for this article

The Review of Financial Studies is currently edited by Itay Goldstein

More articles in The Review of Financial Studies from Society for Financial Studies Oxford University Press, Journals Department, 2001 Evans Road, Cary, NC 27513 USA.. Contact information at EDIRC.
Bibliographic data for series maintained by Oxford University Press ().