Dynamic Leverage
定义动态杠杆取决于对冲基金波动率、时间跨度及净资产价值与清算水平的差距，并形式化为障碍期权，发现中间临界水平下降低风险对避免清算作用有限。
Dynamic leverage as defined here depends on the level of hedge fund volatility, time horizon, and the difference between the fund's net asset value and its critical liquidation level. The critical liquidation level is the level of net asset value loss from which the fund manager could not recover and the fund would need to be liquidated to meet margin calls and redemptions. Dynamic leverage may be formalized very generally as a barrier option. At some intermediate critical level (above the liquidation level), efforts to reduce risk have little influence on the chance the fund will hit the critical liquidation level. A constant dynamic leverage portfolio insurance modifies the more traditional classic portfolio insurance.