Semnan University International Journal of Nonlinear Analysis and Applications 2008-6822 13 1 2022 03 01 Estimating parameters of Marshall Olkin Topp Leon exponential distribution via grey wolf optimization and conjugate gradient with application 3491 3503 6131 10.22075/ijnaa.2022.6131 EN Zeyad M. Abdullah Department of Mathematics, College of Computer Science and Mathematics, Tikrit University, Iraq Nazar K. Hussain Department of Mathematics, College of Computer Science and Mathematics, Tikrit University, Iraq Firas A. Fawzi Department of Mathematics, College of Computer Science and Mathematics, Tikrit University, Iraq Moudher Khalid Abdal-Hammed Department of Public Administration, Collage of Management and Economics, Tikrit University, Iraq Mundher Abdullah Khaleel Department of Public Administration, Collage of Management and Economics, Tikrit University, Iraq Journal Article 2021 03 13 A new probability model for positively skewed datasets like economic data, medical, engineering and other sciences was developed in this paper. The new distribution is named the Marshall Olkin Topp Leon Exponential distribution and it was generated using the Marshall Olkin Topp Leon -G family of distributions. It has three parameters and it is very flexible in fitting several and different datasets. Its basic mathematical properties were studied and two methods like maximum likelihood estimation via Gray Wolf optimization and Conjugate Gradient used for the estimation of model parameters. A real-life dataset was used to illustrate the flexibility of the distribution and it was found that the new model provides a better fit to real-life datasets than other distributions. https://ijnaa.semnan.ac.ir/article_6131_fe80eecd939cbc3393aa8fe93dc1fe84.pdf