In this paper, we suggest a novel method for detecting mortality
deceleration. We focus on the gamma-Gompertz frailty model and suggest the
subtraction of a penalty in the log-likelihood function as an alternative to
traditional likelihood inference and hypothesis testing. Over existing methods,
our method offers advantages, such as avoiding the use of a p-value, hypothesis
testing, and asymptotic distributions. We evaluate the performance of our
approach by comparing it with traditional likelihood inference on both
simulated and real mortality data. Results have shown that our approach is more
accurate in detecting mortality deceleration and provides more reliable
estimates of the underlying parameters. The proposed method is a significant
contribution to the literature as it offers a powerful tool for analyzing
mortality patterns