Mean and Dispersion Charts for Log-Logistic Distribution

The present study aims to develop the robust location and dispersion charts for log-logistic distribution when the value of standard deviation (σ) is unknown and mean absolute deviation from mean used as an estimate based on maximum likelihood estimator and the Bayesian estimators based on Jeffreys and reference priors. The validity of the proposed work has been conducted over the simulation study and the results indicate the Bayesian estimators based on reference prior outperforms in terms of average run length. Finally, two real data sets are analyzed for illustrative purposes.