We introduce a four-parameter lifetime distribution called the odd log-logistic generalized
Gompertz model to generalize the exponential, generalized exponential and
generalized Gompertz distributions, among others.We obtain explicit expressions for
themoments, moment-generating function, asymptotic distribution, quantile function,
mean deviations and distribution of order statistics. The method of maximum likelihood
estimation of parameters is compared by six different methods of estimations
with simulation study. The applicability of the new model is illustrated by means of a
real data set.