To formulate a model that can evaluate the effectiveness of information system safety measurements,the relativity between safety measures counting certain risks (1∶n or m∶1) was studied.Supposing that the effectiveness of different safety measures has abstract function relation,the function was extended into power series by normalization, introduced all possible mathematical relativity,and eliminated redundant relativity by F-statistic and Gram-Schmidt orthography algorithm.By regression analysis,we get the high precision evaluation model than the line evalution model.
