As discussed in Merton (1993, Sections 5 and 6) and here in the section to follow, the effective delivery of many financial services depends critically on the credit-worthiness of the provider financial institution. Such service activities are said to be 'credit-sensitive'. The intermediary's credit standing can cause significant extemality-like effects on the various business activities of the intermediary, even when there are no interconnections among them. For example, the announcement by a U.S. investment bank that it is even thinking of entering into a new merchant-banking activity of extending bridge financing and other interim risk-taking positioning for restructuring firms can materially and negatively affect its over-the-counter derivatives-products business for corporate customers because those customers may perceive the risk of the merchant-banking involvement as jeopardizing the bank's ability to fulfill its obligations on its long-dated contractual agreements. Thus the potential merchant-banking business affects the derivative-products business although there is no overlap of personnel, customer base, location, or employee skill sets between them. The shared credit standing of the institution's individual businesses can therefore cause a significant failure ofthe principle of 'value-additivity', which complicates decentralization of the capital budgeting and financial decisions. The issue of monitoring credit quality are made more complex because those intermediaries such as banks and insurance companies that are principals to customer contractual agreements tend to be 'opaque' institutions, as defined in Ross (1989) and Merton

It is not uncommon on occasions such as this to talk about the shortcomings in the theory of Finance, and to emphasize how little progress has been made in answering the basic questions in Finance, despite enormous research efforts. Indeed, it is not uncommon on such occasions to attack our basic "mythodology, " particularly the "Ivory Tower " nature of our assumptions, as the major reasons for our lack of progress. Like a Sunday morning sermon, such talks serve many useful functions. For one, they serve to deflate our professional egos. For another, they serve to remind us that the importance of a contribution as judged by our professional peers (the gold we really work for) is often not closely aligned with its operational importance in the outside world. Also, such talks serve to comfort those just entering the field, by letting them know that there is much left to do because so little has been done. While such talks are not uncommon, this is not what my talk is about. Rather, my discussion centers on the positive progress made in the development of a theory of Finance using the continuous-time mode of analysis. Hearing this in.1975, amidst an economic recession with a baffling new disease called "stagflation " and with our financial markets only beginning to recover from the worst

The characteristics of the mean-variance, efficient portfolio frontier have been discussed at length in the literature. However, for more than three assets, the general approach has been to display qualitative results in terms of graphs. In this paper, the efficient portfolio frontiers are derived explicitly, and the characteristics claimed for these frontiers are verified. The most important implication derived from these characteristics, the separation theorem, is stated and proved in the context of a mutual fund theorem. It is shown that under certain conditions, the classic graphical technique for deriving the efficient portfolio frontier is incorrect.

Journal Article An Asymptotic Theory of Growth Under Uncertainty Get access Robert C. Merton Robert C. Merton Massachusetts Institute of Technology Search for other works by this author on: Oxford Academic Google Scholar The Review of Economic Studies, Volume 42, Issue 3, July 1975, Pages 375–393, https://doi.org/10.2307/2296851 Published: 01 July 1975

The expected market return is a number frequently required for the solution of many investment and corporate finance problems, but by comparison with other financial variables, there has been little research on estimating this expected return. Current practice for estimating the expected market return adds the historical average realized excess market returns to the current observed interest rate. While this model explicitly reflects the dependence of the market return on the interest rate, it fails to account for the effect of changes in the level of market risk. Three models of equilibrium expected market returns which reflect this dependence are analyzed in this paper. Estimation procedures which incorporate the prior restriction that equilibrium expected excess returns on the market must be positive are derived and applied to return data for the period 1926–1978. The principal conclusions from this exploratory investigation are: (1) in estimating models of the expected market return, the non-negativity restriction of the expected excess return should be explicity included as part of the specification: (2) estimators which use realized returns should be adjusted for heteroscedasticity.

A general formula is derived for the price of a security whose value under specified conditions is a known function of the value of another security. Although the formula can be derived using the arbitrage technique of Black and Scholes, the alternative approach of continuous-time portfolio strategies is used instead. This alternative derivation allows the resolution of some controversies surrounding the Black and Scholes methodology. Specifically, it is demonstrated that the derived pricing formula must be continuous with continuous first derivatives, and that there is not a ‘pre-selection bias’ in the choice of independent variables used in the formula. Finally, the alternative derivation provides a direct proof of the Modigliani-Miller theorem even when there is a positive probability of bankruptcy.

The validity of the classic Black-Scholes option pricing formula depends on the capability of investors to follow a dynamic portfolio strategy in the stock that replicates the payoff structure to the option. The critical assumption required for such a strategy to be feasible, is that the underlying stock return dynamics can be described by a stochastic process with a continuous sample path. In this paper, an option pricing formula is derived for the more-general case when the underlying stock returns are generated by a mixture of both continuous and jump processes. The derived formula has most of the attractive features of the original Black-Scholes formula in that it does not depend on investor preferences or knowledge of the expected return on the underlying stock. Moreover, the same analysis applied to the options can be extended to the pricing of corporate liabilities.

An intertemporal model for the capital market is deduced from the portfolio selection behavior by an arbitrary number of investors who aot so to maximize the expected utility of lifetime consumption and who can trade continuously in time. Explicit demand functions for assets are derived, and it is shown that, unlike the one-period model, current demands are affected by the possibility of uncertain changes in future investment opportunities. After aggregating demands and requiring market clearing, the equilibrium relationships among expected returns are derived, and contrary to the classical capital asset pricing model, expected returns on risky assets may differ from the riskless rate even when they have no systematic or market risk. ONE OF THE MORE important developments in modern capital market theory is the Sharpe-Lintner-Mossin mean-variance equilibrium model of exchange, commonly called the capital asset pricing model.2 Although the model has been the basis for more than one hundred academic papers and has had significant impact on the non-academic financial community,' it is still subject to theoretical and empirical criticism. Because the model assumes that investors choose their portfolios according to the Markowitz [21] mean-variance criterion, it is subject to all the theoretical objections to this criterion, of which there are many.4 It has also been criticized for the additional assumptions required,5 especially homogeneous expectations and the single-period nature of the model. The proponents of the model who agree with the theoretical objections, but who argue that the capital market operates as if these assumptions were satisfied, are themselves not beyond criticism. While the model predicts that the expected excess return from holding an asset is proportional to the covariance of its return with the market