Investors shuttled between optimism and pessimism Wednesday, finally betting that the government might help the economy out of recession after all. News late in the session that key lawmakers agreed on a $790 billion economic stimulus plan sent stocks moderately higher in a partial rebound from a plunge Tuesday that took the Dow Jones industrials down 382 points. Stocks meandered for much of Wednesday's trading as investors struggled for a second day over what to make of developments in Washington. The government has been the biggest player on Wall Street this week. Anthony Conroy, managing director and head trader for BNY ConvergEx Group, said investors are simply trying to keep ahead of the rush of news about the banking system and the economy.