of attributes having similar values for the objects. Such a pair can be represented as an inclusion-maximal rectangle in the numerical table, modulo rows and columns permutations. In it was shown that biclusters of similar values correspond to triconcepts of a triadic context where the third dimension is given by a scale that represents numerical attribute values by binary attributes. This fact can be generalized to n-dimensional case, where n-dimensional clusters of similar values in n-dimensional data are represented by n+1-dimensional concepts. This reduction allows one to use standard definitions and algorithms from multidimensional concept analysis for computing multidimensional clusters. Knowledge spaces In the theory of knowledge spaces it is assumed that in any knowledge space the family of knowledge states is union-closed. The complements of knowledge states therefore form a closure system and may be represented as the extents of some formal context. Hands-on experience with formal concept analysis The formal concept analysis can be used as a qualitative method for data analysis. Since the early beginnings of FBA in the early 1980s, the FBA research group at TU Darmstadt has gained experience from more than 200 projects using the FBA (as of 2005). Including the fields of: medicine and cell biology, genetics, ecology, software engineering, ontology, information and library sciences, office administration, law, linguistics, political science. Many more examples are e.g. described in: Formal Concept Analysis. Foundations and Applications, conference papers at regular conferences such as: International Conference on Formal Concept Analysis (ICFCA), Concept Lattices and their Applications (CLA), or International Conference on Conceptual Structures (ICCS). See also Association rule learning Cluster analysis Commonsense reasoning Conceptual analysis Conceptual clustering Conceptual space Concept learning Correspondence analysis Description logic Factor analysis Graphical model Grounded theory Inductive logic programming Pattern theory Statistical relational learning Schema (genetic algorithms) Notes References External links A Formal Concept Analysis Homepage Demo Formal Concept Analysis. ICFCA International Conference Proceedings 2007 5th 2008 6th 2009 7th 2010 8th 2011 9th 2012 10th 2013 11th 2014 12th 2015 13th 2017 14th 2019 15th 2021 16th Machine learning Lattice theory Data mining Ontology (information science) Semantic relations