However, conventional SOMs handle only numerical data, categorical data has to be converted to Boolean data resulting in unable to disclosure the similarity among the high-dimensional data.

• 然而，传统自组映射图只能处理数值型资料，种类型资料必须透过编码转换成一群二元数值型态资料，因而无法反映种类型资料值之间的相似程度。