EFICIÊNCIA ECONÔMICA: UMA APLICAÇÃO DO MODELO DE FRONTEIRA ESTOCÁSTICA EM EMPRESAS DE SANEAMENTO

The objective of the present study, is measure the efficiency in the sector of basic sanitation. Verifying the existence of economical efficiency among basic sanitation companies on Sao Paulo State, according to the different products determination, assuming two types of systematical errors (half-normal and truncated-normal), as well as, the covered services: regional and local. To perform that, it has been evaluated the efficiency existence on the companies, on Sao Paulo State, using the data from the 'Sistema Nacional de Informação sobre Saneamento' (SNIS), of 2002, from Cities Ministry; through stochastic frontier models of cost function to each type of output used as the dependent variable. It is possible to conclude that, according to the different determinations of outputs, and the assumed distribution of the systematic error, the results has presented different results. That way, the determination of the efficiency is sensible to the choice of output. Performed tests have showed that covered services of the companies were not significant to determine a result. This allows that is possible decrese costs of this enterprises and hold the service's level.