Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Based on daily prices (amtliche Kurse) we estimate effective spreads of securities traded at the Berlin Stock Exchange in 1880, 1890, 1900 and 1910. Several extensions of the Roll measure are applied. We find surprisingly tight effective spreads for the historical data, comparable with similar measures of the MDAX and DAX at the end of the 20th century. Copyright Oxford University Press Science+Business Media, LLC 2006