TY  - JOUR
AU  - Friedman,Benjamin M.
TI  - THE SUBSTITUTABILITY OF DEBT AND EQUITY SECURITIES
JF  - National Bureau of Economic Research Working Paper Series
VL  - No. 1130
PY  - 1983
Y2  - May 1983
UR  - http://www.nber.org/papers/w1130
L1  - http://www.nber.org/papers/w1130.pdf
N1  - Author contact info:
Benjamin M. Friedman
Department of Economics
Littauer Center 127
Harvard University
Cambridge, MA  02138
Tel: 617/495-4246
Fax: 617/495-7730
E-Mail: bfriedman@harvard.edu
AB  - This paper investigates empirically the degree of substitutability between debt and equity securities in the United States during 1960-1980. The analysis first applies fundamental relationships connecting portfolio choices with expected asset returns to infer key asset substitutabilities directly from the observed U.S. asset return experience. It then compares these implied substitutabilities with the observed portfolio behavior of U.S. households. The resulting evidence provides little ground for any conclusion about even the sign, much less the magnitude, of the substitutability of short-term debt and equity. Although the implied optimal behavior indicates that these two assets are substitutes, the observed behavior indicates that households have treated them as complements. By contrast, the evidence consistently indicates that long-term debt and equity are substitutes. Moreover, with a few exceptions the empirical estimates of the associated substitution elasticity are quite closely clustered around the value -.035. The conclusion that long-term debt and equity are substitutes with elasticity -.035 bears mixed implications for broader economic and financial questions. At one level, the finding that the two assets are indeed substitutes validates the standard assumption underlying a variety of familiar models in monetary economics and finance. At the same time, if the elasticity is only -.035, then many of these models' more important substantive conclusions do not follow.
ER  -