Nhà đầu tư mua chứng khoán tài chính phải đối mặt với rủi ro vì họ không biết chắc chắn giá bán tương lai của các chứng khoán của họ, cũng không phải dòng tiền họ sẽ nhận được trong khi chờ đợi. | Part Two The risk of securities and the cost of capital After having covered the basics of finance discounting capitalisation value and interest rates it is time to delve deeper into another fundamental concept risk. Risk is the uncertainty over future asset values and future returns. For better or for worse without risk finance would be quite boring Risk means uncertainty today over the cash flows and value of an asset tomorrow. Of course it is possible to review all the factors that could have a negative or positive impact on an asset quantify each one and measure the total impact on the asset s value. In reality it is infinitely more practical to boil all the risks down to a single figure. Chapter 21 Risk and return It takes two to tango. Investors who buy financial securities face risks because they do not know with certainty the future selling price of their securities nor the cash flows they will receive in the meantime. This chapter will try to understand and measure this risk and also examine its repercussions. Section Sources of risk First it is useful to begin by explaining the difference between risk and uncertainty. This example adapted from Bodie and Merton 2000 describes it quite nicely RISK AND UNCERTAINTY Suppose you would like to give a party to which you decide to invite a dozen friends. You think that 10 of the 12 invitees will come but there is some uncertainty about the real number of people that will eventually show up - 8. This situation can be risky only if the uncertainty affects your plan for the party. For example in providing for your guests suppose you have to decide how much food to prepare. If you knew for sure that 10 people will show up then you would prepare exactly enough for 10 - no more and no less. If 12 actually show up there will not be enough food and you will be displeased with that outcome because some guests will be hungry and dissatisfied. If 8 actually show up there will be too much food and you will be displeased
