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Good to know:
Calculating the Gindex in RiskMetrics after 2007
Riskmetrics made significant changes to their data sources and methodology starting in 2007. As a result, many of the inputs needed to calculate the Gindex are no longer available. You can check the website of or contact ...
Winner's Curse in Acquisitions (Academic Paper) (view source)
Revision as of 18:17, 15 November 2016
, 18:17, 15 November 2016→Governance_Final Table (Amir)
E:\McNair\Projects\Winner's Curse\Governance\RiskMetrics-0b578b37fbb59afa.txt
Merging EXECUCOMP AND IRRC:
Q) What is the best way to merge Execucomp and IRRC (director and governance) databases? I understand they both have CUSIP, but that matching with CUSIPs isn't always ideal since the CUSIP can change over time for the same firm.
A) All Execucomp (CUSIP), IRRC Governance (CN6), and IRRC Directors (CUSIP) CUSIPs are header cusips, in that they reflect the most recent CUSIP that the company has had. There are however 2 main differences between Execucomp's CUSIP and IRRC's CUSIP and CN6:
1. While Execucomp uses 8-digit CUSIP, both IRRC datasets have 6-digit CUSIPs. Therefore, you need to use a SAS function like "substr" to take the first 6-digit of Execucomp CUSIP before merging it to IRRC data. ex: cusip6 = substr(CUSIP,1,6);
2. While header convention reflect "most recent" value of an identifier variables, it is dependent on the date of update of each dataset. Therefore, for CUSIPs that change in between the time that both databases are updated, you might find some discrepancy. To overcome this issue, we recommend that you make use of the CRSP name files (ex: stocknames), that contains all historical CUSIPs that a company has had.
Also, good to know:
Best Identifier to Use in RiskMetrics Directors- Changes to Identifier between Legacy and Current Files
1. The primary identifier in the current dataset is year-ticker-director_detail_id. Ticker is better populated than cusip in earlier years, but should be about the same in the latest years. For the legacy directors, director_detail_id was in use for some years and legacy_director_id for others.
