The authors sustain that assessing market efficiency based on price levels is similar to assessing the outcome of buying or selling short a share once, and keeping that position forever. The price level criterion is clearly less sensitive to cases of transaction and negotiating costs employed by an efficient market. In addition, the price level criterion is interesting for investors who for some reason is obliged to maintain the asset for an extended period. For example, price levels are an appropriate measure for a large number of economic decisions, such as for the firm’s investments and for mergers and acquisitions, which imply essentially in decisions with the typical behavior of buying and maintaining an asset (Cohen, Polk, and Vuolteenaho, 2009).