TheLAMBDAmethodthatwasproposedbyTeunissenisintroduced.Then,onthebasisofboththeback-sequentialconditionalLStechniqueandtheupper-triangularCholeskydecomposition,anotherformforLAMBDAmethodisproposed.ThisnewformforLAMBDAmethodhasthesameprincipleandcalculationspeedasthetraditionalLAMBDAmethod.