Lecture 22
Only non-observable variable Historical volatility Predictive models ◦ ARCH (Robert Engel) ◦ GARCH Weighted Average Historical Volatility Implied Volatility VIX – Exchange traded volatility option ◦ 1993 ◦ S&P 500 Implied Volatility
Implied Volatility is highest where time premium is highest…usually at the money Time Decay Option Price Stock Price Days to Expiration
Term Structure of Volatilities
Strike Price Asset Price Implied Volatility
Strike Price Asset Price Implied Volatility
Strike Price Asset Price Implied Volatility
Ginnie Mae (Govt guaranteed) Freddie Mac (Private) Fannie Mae (Private) Mortgage Conduits Funding sources for mortgages How mortgages and MBS are created
MBS – Mortgage backed security CMO - collateralized mort obligations ◦ CDO – Collateralized debt obligation REMIC - real estate mortgage investment conduits Subprime mortgages ◦ Private label funding
Stripped Mort backed Securities (SMBS) Variable maturity tranche Variable/Fixed rate tranche Principal Only (PO) Interest Only (IO)
Valued similar to bonds (fixed incomes) Factors Prepayment Weighted average coupon (WAC) Weighted average maturity (WAM) Required yield (YTM) Default