Since the first owner of a gold depository discovered that profits could be made by lending some of the gold deposited for safekeeping, there has been a concern for the “capital adequacy” of depository institutions. The idea is simple enough. If the value of an institution's assets may decline in the future, its deposits will generally be safer, the larger the current value of assets in relation to the value of deposits. Defining capital as the difference between assets and deposits, the larger the ratio of capital to assets (or the ratio of capital to deposits) the safer the deposits. At some level capital will be “adequate,” i. e., the deposits will be “safe enough.”

This paper is a pioneering effort in the examination of the workings of rationality and efficiency in capital markets. The central theme of the paper is the notion of informational efficiency in markets for durable assets. In its broadest terms this imposes a behavioral constraint on the intertemporal development of the asset markets; in a perfect market the development of the equilibrium over time must not be self-contradictory. Individual agents' anticipations of future developments determine their current actions and these, in turn, determine equilibrium prices. But, tomorrow the process will be repeated and it is at this second step that the possibility of conflict enters. The future development need not fulfill precisely people's previous anticipations, but in a perfectly functioning market it would be difficult to accept a blatant contradiction. To believe that prices are lognormally distributed, for example, and to have that belief generate the same equilibrium price period after period is such a contradiction.

Estimation and control of security risk are subjects of major theoretical and practical importance. Much of the literature in this area has focused on the risk associated with returns over a single holding period. Within this context, a great deal of attention has been devoted to estimation of security betas, which relate to coveriance with “the market,” since the well-known Capital Asset Pricing Model implies that expected returns will, in equilibrium, be related to such values. However, a number of papers [3, 7, 14] have considered “extra-market covariances,” i.e., covariances among security returns not due to common correlations with the market as a whole. Accurate estimates of such covariances are necessary for tailoring portfolios to account for differences in investors' circumstances (e.g., tax brackets) and, a fortiori, for active portfolio management designed to exploit any security mispricing.

These three papers deal with a common subject from three very different attitudes and perspectives. As a result, without challenging such restrictive conventions as the assumption that investor holding periods are fixed and knowable a priori or indeed disagreeing on anything of substance, the respective sets of authors sound three very different themes.

The bitter opposition of businessmen to the New Deal in its early stages is well known. Not so well known, however, are the efforts of a few business leaders to maintain constructive communication with the President and his advisers. Professor Collins traces these efforts, from the early stages during which both groups labored in mutual distrust, through the remarkable transformation in which such strong business personalities as Beardsley Ruml, William Benton, and Paul Hoffman helped persuade a deeply conservative Franklin D. Roosevelt to adopt compensatory deficit spending as a means to recovery. Finally, he shows that World War II marked not the end but a continuation of these positive efforts by businessmen to adapt to the new philosophy, and led directly to the founding of the Committee for Economic Development.