Weighted Naive Bayes Classifier in Medical

Data mining is an essential step in the process of knowledge discovery in databases in which intelligent methods are applied in order to extract patterns (K. Usha Rani, 2010). Data Mining (Perichinsky G. et al.,2003) is the set of techniques and tools applied to the non-trivial process of extracting and presenting/displaying implicit knowledge, previously un-known, potentially useful and humanly comprehensible, from large data sets, with object to predict automated form tendencies and behaviors; and to describe auto-mated form models previously unknown(Chen M .et al.,1996) (Mannila H.et al.,1997) ( Piatetski-Shapiro G.et al.,1991).The applications of data mining in medical and health research have proved themself to be effective, showing great development potentialities. Medical data mining has great prospective for exploring hidden patterns in data sets .The term intelligent data mining( Evangelos S.et al.,1996) is the application of automatic learning methods ( Michalski R.S.et al.,1983) (Holsheimer M.et al.,1991)to discover and enumerate present patterns in the data.