They are private investors or executives responsible for their company's treasury, or consultants, or investment managers, or just plain stock market enthusiasts. To sharpen decision-making skills in the light of incomplete information or uncertainties inherent to stock movements, they purchase software games that simulate a real-life stock market. In the game, the player starts with a hypothetical amount of money for investment in stocks. He then buys shares of listed companies. As the game progresses, news about global, regional, and national economies are flashed, together with developments in many industries and in the listed companies themselves. Reacting to the news, and making his own forecast, the player sells, buys, or holds on to his shares. When the game ends, the value of his holdings vis-à-vis the value at the start will show the soundness of his decisions.