Abstract: A credit account management system comprises a refund method management unit, and a credit limit setting unit. The refund method management unit receives the designation of a refund method of the outstanding credit-loan amount in the credit account after integration from the user, and sets the refund method of the outstanding credit-loan amount in the credit account after integration. After credit accounts are integrated, the outstanding credit-loan amount is refunded according to the refund method set by the refund method management unit. The credit limit setting unit compares the outstanding credit-loan amount in the credit account after integration and a target credit limit which is expected to be given in the credit account after integration, and sets a credit limit in the credit account after integration based on the comparison result.

Abstract: A deal processing apparatus, which clinches a deal by intermediating a sell order and a buy order, comprises a sell/buy determining unit clinching a deal by determining a pair of sell and buy orders with which a deal is to be clinched. The sell/buy determining unit obtains a sell/buy profit by clinching a first deal with sell and buy orders in which a desired sell price is lower than a desired buy price. Then, the sell/buy determining unit clinches a second deal with sell and buy orders in which a desired buy price is lower than a desired sell price. A quantity to be dealt in the second deal is determined so that a sell/buy loss that a broker suffers in the second deal does not exceed the sell/buy profit that the broker obtains in the first deal. In this way, a deal is clinched while reducing the risk that a broker who intermediates orders with this dealing method suffers a sell/buy loss, even if a desired sell price of a sell order does not match a desired buy price of a buy order.

Abstract: A securities selection support method and securities selection support program that can clearly indicate the characteristics of a risk on an investment in a financial instrument selected optionally. A computer selects proposed investment securities to be invested in from among a plurality of securities. Then the computer calculates investment risk standard values according to a plurality of risk indexes on the basis of investment risk information in which an investment risk regarding the plurality of risk indexes is set for each of the plurality of securities. And then the computer calculates deviations according to the plurality of risk indexes by comparing the investment risk standard values according to the plurality of risk indexes and a risk on an investment in the proposed investment securities (or a compound investment risk calculated from risks on investments in a plurality of proposed investment securities).