An investor who wants to invest a certain amount and to whom a lot of more or less risky alternatives arise would divide this amount among several securities. He makes this portfolio decision because of his expectations with regard to these assets which result from the information available to him. If the investor obtains additional information, then his knowledge would improve and, therefore, the portfolio decision made by him. Accordingly, he will be ready to accept certain costs related to the information procurement. The value of information indicates the maximum tolerable information...