The Non-equal-interval Direct Verhulst GM(1,1) Model with Two Times Fitting and its Application to Test Data Processing

Test data processing is an important role in test process. The principle, under which the Grey systems theory is applied in data processing, is that the test system can be considered as a Grey system. In such a system, unknown system's information can be determined by using known information. The non-equal-interval direct Verhulst GM(1,1) model through two times fitting was built which extended equal interval to non-equal-interval and suited for general data modeling and estimating parameters of direct Verhulst GM(1,1). The new model need not pre-process the primitive data, accumulated generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suited for equal interval data modeling, but also for non-equal interval data modeling. Its calculation is simple, higher accuracy and used convenient. The example shows that the new model is simple and practical. The new model is worth expanding and applying in test data processing or test on-line monitoring.