For the performance degradation reliability analysis

comparison of bilinear process method and group test method was conducted. The modeling procedure of these two methods was theoretically discussed. It can be found consequently that

the analysis precision of bilinear process method can be improved based on the one-stage estimation process

helping to avoid information waste. A reported window wiper switch performance degradation test was then considered to verify these two methods. Comparative analysis of the 10th percentile curve indicates that

the bilinear process method with 2.5% upper test data

can derive more reasonable results

compared with the group test method with 15% upper test data. In addition

model validation based on the residual analysis illustrates the effectiveness of the bilinear process method.