We give a simple explicit formula for turnover reduction when a large number of alphas are traded on the same execution platform and trades are crossed internally. We model turnover reduction via alpha correlations. Then, for a large number of alphas, turnover reduction is related to the largest...

This comparison of expected versus realized turnover in institutional equity portfolios reveals that 65%of portfolios turn over more than expected, some by large amounts.Manager interviews indicated they were aware that excessive turnover was potentially harmful to their clients. They cited...