The failure intensity for a basic model as a function of failures experienced is given as $\lambda (\mu) - \lambda_0[1-(\mu)/(V_0)]$ where $\lambda_0$ is the initial failure intensity at the start of the execution, $\mu$ is the average or expected number of failures at a given point in time, the quantity $V_0$ is the total number of failures that would occur in infinite time.
Assume that a program will experience 100 failures in infinite time, the initial failure intensity was 10 failures/CPU hr. Then the decrement of failures intensity per failure will be
- 10 per CPU hr
- 0.1 per CPU hr
- -0.1 per CPU hr
- 90 per CPU hr