Alternative Emhs The weak-form emh assumes that stock prices fully reflect all security-market information Including the historical of price, rates of return, trading volume data, and other market-generated information such as block trades short interest odd-lot transactionsAlternative EMHs • The weak-form EMH assumes that stock prices fully reflect all security-market information. – Including the historical of price, rates of return, trading volume data, and other market-generated information, such as block trades, short interest, odd-lot transactions