Statistics for Maintenance Modelling: Proportional Hazards and Accelerated Life Models

# Example of the Proportional Hazards Model¤

Suppose the baseline hazard is , and the parameters are = 0.01, = 2, then at time t = 100:

h0(t) = 0.02.

If we take into account covariates where 1 = 0.5, n = 1 and y1 = 1, then at time t = 100 we have:

= 0.032.

Similarly if y1 = -1, we have:

h(t; y) = 0.012 at t = 100.

This demonstrates how the hazard will change if the influence of covariates is considered.