Abstract
Approximate and generalized confidence bands for some parametric functions
of the univariate lognormal diffusion process with exogenous factors are obtained.
The procedures to obtain these bands are developed from the suitable adaptation of
the available methods for building confidence intervals for the mean of the lognormal
distribution. The obtained bands are similar to those calculated for the homogeneous
lognormal diffusion process but, in this case it is not possible a general comparative
study in terms of coverage errors, by means of simulation studies, because of the dependence
on the exogenous factors of each particular model. Therefore, in each case
a particular study is necessary. In this sense, in this paper two models are considered
modelling the gross national product of Spain and the global manmade methane
emissions, respectively.
