Multivariable Relationships: General Log-Linear and Proportional Hazards

So far in this reference, the life-stress relationships presented have been either single stress relationships or two stress relationships. In most practical applications however, life is a function of more than one or two variables (stress types). In addition, there are many applications where the life of a product as a function of stress and of some engineering variable other than stress is sought.

In this chapter, the general log-linear relationship and the proportional hazards model are presented for the analysis of such cases where more than two accelerated stresses (or variables) need to be considered.

This chapter includes the following subchapters:

General Log-Linear Relationship
Proportional Hazards Model
Indicator Variables