Data analyzed by Kandala et al. (2001) which is used for demonstrative purposes to estimate linear mixed and additive models using a stepwise procedure on the basis of the cAIC. The full data set is available at https://www.uni-goettingen.de/de/551625.html.
Kandala, N. B., Lang, S., Klasen, S., Fahrmeir, L. (2001): Semiparametric Analysis of the Socio-Demographic and Spatial Determinants of Undernutrition in Two African Countries. Research in Official Statistics, 1, 81-100.