Aplicação de modelos multiníveis na análise de dados de medidas repetidas no tempo. / Multilevel models applied in the analysis of repeated measure data.
AUTOR(ES)
Genevile Carife Bergamo
DATA DE PUBLICAÇÃO
2002
RESUMO
It is common to and data structured in a hierarchical form in several scientific works, that is, the studied subjects are nested in the lowest level unites, that belong to the highest level unites, and so on. To analyze these sort of data it is important to take in account the hierarchical structure once, if does not do it, the coeficients can be overestimated in the studied model. Then, in order to become easier the data analysis according to the hierarchical structure, multilevel models were developed. Such models take into account all the existing variability for the data at the same level as well as in diferent levels of the hierarchy. In the case of repeated measure data, a two levels hierarchical structure can be considered, organizing the occasions at the first level for each subject at the second level. In this work, na approach of the multilevel models for several levels are made as well as the estimation methods and the tests for the involved parameters in the model. As an application, data from the Elderly Care Program (ECP), developed at outpatient clinic Dr. Plinio do Prado Coutinho at Alfenas, M.G., where the Body Mass Index and the Bloody Pressure were observed from elderly people for 22 months. Also, it was analyzed the milk protein content of 79 australian cows during 19 weeks after calving and subject to three diets (Diggle et al., 1994). For the data of the ECP it was possible to observe that the bloody pressure are positively related to the occasions, independently of sex, race and marital status. For the data form the milk protein content, a reduce in the content in the occasions even after the diets are included. MLwiN and SAS softwares were used to run the analysis.
ASSUNTO(S)
applied statistics análise de dados mathematical models estatística aplicada repeated measures modelos matemáticos data analysis medidas repetidas
Documentos Relacionados
- "Modelos lineares generalizados para análise de dados com medidas repetidas"
- Modelos elípticos multiníveis
- Uma abordagem para análise de dados com medidas repetidas utilizando modelos lineares mistos
- Técnicas de diagnóstico para modelos lineares generalizados com medidas repetidas
- Modelos lineares generalizados mistos para dados longitudinais.