In Abaqus 2019, there is a new function which called "Missing mass method". This method is similar to residual mode in linear dynamics, the main goal is to enhance accuracy cause we always extract limited number of frequency. 

I've searched 2019 manual, it seems "Missing mass method" only available for "response spectrum analysis"? Is that true? I'm not familiar with the theory behind "Missing mass method, hope somebody can give some advice. Thanks a lot!