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Análise Psicológica

versão impressa ISSN 0870-8231

Aná. Psicológica v.21 n.2 Lisboa abr. 2003

 

Algumas medidas típicas univariadas da magnitude do efeito (*)

 

JOSEPH EDWARD CONBOY (**)

 

 

RESUMO

As medidas de magnitude do efeito representam uma resposta eficaz às diversas críticas às metodologias de investigação tradicionalmente utilizadas nas ciências sociais. Tais medidas evitam algumas das dificuldades mais evidentes dos testes de hipótese; são de interpretação simples, sem o recurso a valores de p, que podem ser enganadores; e fornecem uma base para a síntese de grande número de estudos. Este artigo descreve o cálculo e interpretação das formas mais comuns desta abordagem alternativa, ou complementar, aos testes de hipótese. Pressupõe-se que o leitor dispõe de um conhecimento básico de estatística aplicada sem ter, necessariamente, uma forte formação em estatística matemática.

Palavras-chave: Magnitude do efeito, Métodos de Investigação, Análise de Dados, Ciências Sociais.

 

 

ABSTRACT

Measures of effect size represent an alternative to traditional methods of data analysis in the social sciences. These metrics avoid some of the most evident problems associated with tests of hypotheses, are more simply interpreted than sometimes misleading p values, and provide the basis for the synthesis of large numbers of research studies. This text assumes that the reader has a basic understanding of inferential statistics and describes the calculation and interpretation of common forms of effect size that can be used either as alternatives, or complements, to classical hypothesis testing.

Key words: Effect size, Research methods, Data analysis, Social Sciences.

 

 

Texto completo disponível apenas em PDF.

Full text only available in PDF format.

 

 

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(*) Agradecimentos: Gostava de agradecer à Professora Jesuína M. B. Fonseca, da Universidade do Algarve, e A. K. Conboy da Universidade de Bowdoin que comentaram uma versão anterior do trabalho. Gostava igualmente de mencionar o meu reconhecimento aos responsáveis das Bibliotecas Guttman da Harvard Graduate School of Education e Milbank da Columbia University que possibilitaram o acesso a algumas das referências incluídas no artigo.

(**) Instituto Superior Dom Afonso III, Loulé, Portugal.

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