@article{Hamasha_2017, place={Greece}, title={A Mathematical Approximation of the Left-sided Truncated Normal Distribution Using the Cadwell Approximation Model}, volume={7}, url={https://etasr.com/index.php/ETASR/article/view/988}, abstractNote={<p style="text-align: justify;">In the case that life distribution of new devices follows the normal distribution, the life distribution of the same brand used devices follows left-sided truncated normal distribution. In spite of many mathematical models being available to approximate the normal distribution density functions, there is a few work available on modeling/approximating the density functions of left-sided truncated normal distribution. This article introduces a high accuracy mathematical model to approximate the cumulative density function of left-sided truncated standard normal distribution defined on the range of [truncation point (ZL): ∞]. The introduced model is derived from the Cadwell approximation of the normal cumulative density. The accuracy level change with Z score is discussed in details. The maximum deviation of the model results, from the real results for the whole region of [-∞<Z<-2:<span>∞</span>], is 0.006877.<strong></strong></p>}, number={1}, journal={Engineering, Technology & Applied Science Research}, author={Hamasha, M. M.}, year={2017}, month={Feb.}, pages={1382-1386} }