Araújo, Mariana Correia deFerreira, Luana Brenda Pontes2018-12-182021-09-202018-12-182021-09-202018-12-13FERREIRA, Luana Brenda Pontes. Estudo sobre os modelos não-lineares simétricos: aspectos inferenciais e aplicações. 2018. 40 f. Trabalho de Conclusão de Curso (Graduação em Estatística) - Departamento de Estatística, Universidade Federal do Rio Grande do Norte, Natal, 2018.https://repositorio.ufrn.br/handle/123456789/34316Outliers appear in the analyses of various datasets, which can affect the parameter estimation by distorting the point estimations, for instance. One way to deal with datasets that have outliers is to suppose a distribution for the model erros that possesses heavier tails than those of the normal distribution. Models that suppose that the errors are distributed according to the symmetrical family is an alternative to the normal distributions in these cases, and have been frequently used in the literature, seeing as the models are less sensitive to the presence of annomalies. On the other hand a linear model does not always fit well to the observations of a dataset, hence making it necessary to have a non-linear structure for modelling the data. This piece aims to study non-linear symmetrical models. To accomplish this, different distributions belonging to the symmetrical families are presented, the non-linear symmetrical model is chosen, inferential aspects, iterative processes for the estimation of the chosen model's parameters and some assymptotic results with the estimator and hypothesis test properties are developed. Lastly, applications made to three real datasets are done using the R language.Attribution-NonCommercial-NoDerivs 3.0 Brazilhttp://creativecommons.org/licenses/by-nc-nd/3.0/br/Distribuições simétricasEstimação de parâmetrosModelo não-linear simétricoSymmetrical distributionsParameter estimationNon-linear symmetrical model.bachelorThesis