[Bayesian rates for homicide mapping in Brazilian municipalities]

This study analyzes homicide incidence per municipality (county) in Brazil in the year 2008. The authors estimate and compare homicide rates according to different methods, finding evidence that depending on the method employed, the results can differ significantly, especially for small municipalities. Bayesian spatial procedures were employed, allowing minimization of variation in the rate estimates. The methods consider a priori distributions and information on contiguity of municipalities. According to the findings, the impact of corrective procedures is not relevant for large municipalities, but such estimates present significant differences for small municipalities. Comparing the different estimates, the authors conclude that there may be distortions in the rates published in the literature. To overcome such potential distortions, it is necessary to take the main goal in each analysis into account. When the emphasis is on overall visualization of the homicide phenomenon, the best option is spatial corrections. However, to obtain more accurate local estimates, Bayesian methods are more appropriate.