future fair value and the actual index level. As the derivative is based on the index, the two should normally have a very close relationship. If there is a sufficiently large difference the arbitraging program will attempt to buy the relatively cheap level (whether that is the basket of stocks which make up the index or the index future) and sell the relatively expensive product, making money from the price discrepancy. The fair value calculation takes into account the time to expiration of the future contract, the dividends received from holding all the stocks, and the interest cost of buying the stocks. See also Automated trading system Algorithmic trading High-frequency trading Alternative trading system Electronic trading platform Dark pool References Share trading sv:Algoritmisk handel