It is the basis of oas to construct zero coupon yield curve and define interest rate term factors model . the key of oas is to select a kind of interest rate scenario simulation and evaluation methodology fitting abs / mbs 其中,零息票收益曲线的构造和利率期限因素模型的定义是期权调整利差法的基础;选择适合资产抵押支持证券的利率情景模拟技术和估价技术是其关键。