In this article. we analyze informational efficiency in daily returns of NASDAQ. DJIA and S&P 500 indices ranging from 04-01-1980 to 12-09-2013. We replace the traditional coarse graining method used in multi-scale entropy analysis by a Maximal Overlap Discreet Wavelet Transform decomposition and extract Sample entropy measure across different timescales. https://www.jalyttlers.shop/product-category/sand-timer/