Convexity in Ordinal Data
Convexity is a leading idea in data analysis, although it is mostly involved on an informal level; in particular, convexity in ordinal data has not been elaborated as a well defined tool. This paper presents a first discussion of convexity definitions in connection with examples of ordinal data. One result is that there is more than one definition of ordinal convexity which is meaningful for data analysis. Convexity in multi-varied ordinal data is analysed by methods of formal concept analysis. Some relation to Euclidean convexity is outlined.
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