Calculations for Weibull Distribution

Failure Rate

Note: For Weibull Distribution with two parameters, γ=0.

PDF

CDF

MLE

Where is the failure time of component i, i=1,..., r or the censoring time of component i, i=r+1,..., n. If there is no censoring (complete data), r = n.

Least Square

Note: For Weibull distribution with 3 parameters, γ can be obtained by minimizing r-squared of the least square line fit.