  The Brazilian Mathematical Olympiads for Public Schools (OBMEP) is held every
year since 2005. In the 2013 edition there were over 47,000 schools registered
involving nearly 19.2 million students. The Brazilian public educational system
is structured into three administrative levels: federal, state and municipal.
Students participating in the OBMEP come from three educational levels, two in
primary and one in secondary school. We aim at studying the performance of
Brazilian public schools which have been taking part of the OBMEP from 2006
until 2013. We propose a standardization of the mean scores of schools per year
and educational level which is modeled through a hierarchical dynamic beta
regression model. Both the mean and precision of the beta distribution are
modeled as a function of covariates whose effects evolve smoothly with time.
Results show that, regardless of the educational level, federal schools have
better performance than municipal or state schools. The mean performance of
schools increases with the human development index (HDI) of the municipality
the school is located in. Moreover, the difference in mean performance between
federal and state or municipal schools tends to increase with the HDI. Schools
with higher proportion of boys tend to have better mean performance in the
second and third educational levels of OBMEP.
