DESPITE THE THEORETICAL and empirical difficulties in defining and measuring risk, the community is concerned with the investment of alternative securities and firms. This study restricts itself to an analysis of the similarity between two widely employed measures of risk: common stock systematic risk and corporate bond ratings.' The capital asset pricing model [11, 14, 21] specifies that in a properly diversified portfolio, the relevant measure of risk is the covariance of the asset return with the market return divided by the variance of the market return-known as systematic risk or beta. In an efficient market an investor is rewarded only for bearing systematic (i.e., market-wide or non-diversifiable) risk. Systematic risk information is now routinely provided investors by many advisory agencies on a large number of common stocks. A number of recent studies [2, 4, 7] have indicated varying relationships between systematic risk and financialor firm-related estimates of risk. Corporate bond ratings provide a simple indication of the relative risk associated with the fixed income offerings of a large number of publicly owned firms. These ratings, which attempt to look at 'worst' potentialities in the 'visible' future. . [13, p.v.], appear to be based on a combination of objective and subjective factors [16]. Earlier studies have indicated a consistent relationship between bond ratings and actual rates of default [1, 9]. In recent years a number of models for predicting ratings, incorporating a combination of bondrelated and financialor firm-related variables, have been developed [10, 15, 17, 22]. While bond rating agencies do not claim complete precision, the ratings seek to provide the American investor with a simple system of gradation by which relative qualities of bonds may be noted [13, p.v.]. The purpose of this study is to examine the relationship between these two different measures of risk that are readily available to virtually all investors. Given the high level of efficiency in our capital markets [5], and the fact that previous studies of both common stock systematic risk and bond ratings have indicated definite relationships with certain financial variables, we hypothesize that common stock sys-
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