Бригхем Ю., Гапенски Л. Финансовый менеджмент: полный курс: В 2-х т. / Пер. с англ. под ред. В.В.Ковалева.
СПб 2001 г. Т.1.ХХХ+497 с.,Т.2. 669 с.
The Evolution of Financial Theory
Your first finance course probably provided an overview of financial markets and institutions, plus an introduction to specific decisions facing financial managers. This text reviews and reinforces basic financial concepts and then goes on (1) to discuss in detail the theoretical underpinnings of financial management decisions, (2) to present an in-depth treatment of financial management concepts and techniques, and (3) to provide sufficient institutional material to enable you to implement the theory, concepts, and techniques in a real-world setting.
Chapter 1 lays the groundwork for the book by providing an overview of financial theory. Virtually all financial decisions, including capital budgeting, dividend policy, and financing, are predicated upon rules that stem from financial theory. Most financial theory is normative
in the sense that it dictates what financial managers "ought to do." However, positive,
or descriptive, studies are also important. Descriptive studies include both empirical research designed to find relationships among variables, such as the relationship between dividend policy and stock price, and surveys designed to find out what financial managers are actually doing.
Normative theories are clearly important, but positive studies reveal that financial managers do not always do what financial theorists say they should do. This poses a dilemma: Is the theory incorrect, are financial managers acting improperly, or what? The answer is often not clear. In some instances, financial theories simplify the situations with assumptions that are not met in the real world, so the decision rules they produce are simply not valid. In other situations, it is impossible to apply financial theory because we cannot obtain the necessary data. Thus, the theory may be correct, but it can be used only indirectly, to provide insights into decisions. In still other situations, the theory may be correct, and it may also be possible to apply it, but the inertia of doing things the old way may still predominate. Competition, though, will eventually force managers to use valid financial theories to their advantage, so ultimately, inertia will be overcome and valid theories will be applied.
In general, if unexplained differences persist between theory and practice, the theory should be questioned. Indeed, mod-
ern financial theory is predicated on the fact that, to be accepted, theories must explain real-world behavior. When a theory is inconsistent with practice, it must be modified until it is consistent or else scrapped in favor of a superior theory.
In this book, when presenting unreconciled differences that exist either between financial theory and practice or between alternative theories, we will proceed as follows: (1) We first present the relevant financial theory or theories, along with their primary assumptions. (2) We then discuss empirical evidence which supports or refutes each theory. (3) Finally, we present some insights into how practicing financial managers actually make decisions in the face of conflicting theories.1 This approach will allow you to see all sides of an issue, which should enhance your ability to make financial management decisions in the future.
In the remainder of this chapter, we discuss the evolution of key financial theories. The ordering is generally chronological, but related theories have often evolved more or less simultaneously. Also, several theories are associated with their developers, so we will introduce some names along the way. The names of prominent theorists are not as important as the implications of the theories, but they are just as much a part of financial jargon as the names of the various types of securities that firms issue. Finally, keep in mind that our goal in Chapter 1 is to create a general framework for making financial decisions rather than to discuss each theory in detail. We will revisit most of the theories later in the text, as we discuss specific types of financial decisions.
1 These sections are often titled "Our View ...," such as "Our View of the Dividend Policy Decision."