What do the parameters B and C represent in ALTA?
The parameters B and C are used by ALTA for the Arrhenius and temperature-nonthermal life-stress relationships. The application returns values for these variables along with the shape parameter for the selected distribution (beta for Weibull or standard deviation for lognormal). However, it is much more difficult to glean information about the test items from the B and C parameters than from the shape parameter. Essentially, B and C are just variables for which ALTA solves in order to determine the relationship between stress and life; it is difficult to draw any conclusions about the behavior of the products based on the values of these parameters. However, you can get an indication of the nature of the relationship between life and stress from the parameter B. The sign of the B parameter indicates in which direction the life-stress relationship lies. If B is positive, the life of the product decreases with increasing stress. If B is negative, the life of the product increases with in
