The Relevance of Margin Regulations: Note
运用现代金融理论分析保证金要求对个人杠杆、公司估值和信用分配的影响，发现公司行为会部分抵消监管效果，且与1934年《证券交易法》的目标不一致。
Margin credit was singled out for selective credit control in 1934 by the Securities Exchange Act (SEA). This act directed the Federal Reserve Board to regulate security credit so as to the excessive use of credit in the purchase or carrying of securities. The principal objectives of the SEA were: (1) to protect investors from speculative losses, (2) to prevent the speculative securities markets from absorbing credit away from productive commercial and agricultural uses, and (3) to inhibit security price fluctuations due to credit-financed security purchases. ' To date, there has been little research into the effectiveness of margin regulations in attaining the objectives of the SEA.2 One noteworthy exception is a paper by Luckett (1982) which analyzes the efficacy of margin requirements in influencing the investor's degree of personal leverage and risk exposure. However, Luckett's analysis leaves unanswered the impacts of changes in margin requirements on firm valuation, security returns uncertainty, and the allocation of credit in the economy. In this paper modern finance theory is employed to analyze some of these effects. We conclude that corporations will take actions so as to offset, at least in part, the impacts of changes in margin restrictions on personal leverage, and that the effects of margin requirements are generally inconsistent with the objectives of the SEA reformers.