Before revision:  By contrast, completeness is a sufficient and necessary condition for a market to be informationally efficient, i.e., only in that case past and future events turn out to be conditionally independent of the price history  .
After revision:  By contrast, completeness is a sufficient and necessary condition for a market to be informationally efficient, i.e., only in that case past and future events turn out to be conditionally independent of the price history with respect to the physical measure .