# Approximation Operators in Qualitative Data Analysis

@inproceedings{Dntsch2003ApproximationOI, title={Approximation Operators in Qualitative Data Analysis}, author={I. D{\"u}ntsch and G. Gediga}, booktitle={Theory and Applications of Relational Structures as Knowledge Instruments}, year={2003} }

A large part of qualitative data analysis is concerned with approximations of sets on the basis of relational information. In this paper, we present various forms of set approximations via the unifying concept of modal–style operators. Two examples indicate the usefulness of the approach.

#### 134 Citations

Rough approximations in formal contexts

- Computer Science
- 2005 International Conference on Machine Learning and Cybernetics
- 2005

Relationships between the rough set theory and the formal concept analysis are discussed and several types of rough approximation operators on the object set are introduced. Expand

Rough Approximation Operators with Hedges

- Mathematics
- 2009

The theory of formal concept analysis and the theory of rough sets are related. In the paper, from the point of view of graded truth approach, two L-rough operators with hedges are defined, some of… Expand

A Comparative Study of Formal Concept Analysis and Rough Set Theory in Data Analysis

- Computer Science
- Rough Sets and Current Trends in Computing
- 2004

The theory of rough sets and formal concept analysis are compared in a common framework based on formal contexts to produce different types of rules summarizing knowledge embedded in data. Expand

Simplifying Contextual Structures

- Computer Science
- PReMI
- 2015

The ICRA approach offers an effective way to reduce the complexity of a concept lattice and/or a knowledge space by changing only little information in comparison to a competing model which uses fuzzy K-Means clustering. Expand

Rough set approximations in formal concept analysis

- Mathematics, Computer Science
- IEEE Annual Meeting of the Fuzzy Information, 2004. Processing NAFIPS '04.
- 2004

The notion of rough set approximations is introduced into formal concept analysis and approximation operators are defined based on both lattice- theoretic and set-theoretic operators to provide a better understanding of data analysis. Expand

Multiview intelligent data analysis based on granular computing

- Computer Science
- 2006 IEEE International Conference on Granular Computing
- 2006

The mental issues of granulations and granular structures for data analysis are discussed based on modal-style data operators and the results provide a basis for establishing a framework of multiview intelligent data analysis. Expand

Concept Lattices in L-Rough Sets

- Mathematics, Computer Science
- ISNN
- 2009

In this paper, two L-rough approximation operators are defined by an arbitrary L-relation, some of their properties and their relation to Galois connection in Formal Concept Analysis are… Expand

Fuzzy Modal – Like Approximation Operations Based on Residuated Lattices

- 2006

In many applications we have a set of objects together with their properties. Since the available information is often incomplete and/or imprecise, the true knowledge about subsets of objects can be… Expand

Relationships Between Concept Lattice and Rough Set

- Mathematics, Computer Science
- ICAISC
- 2006

By introducing the term of anti-chain formal context, the relation between the reduction of formal context in concept lattice and attribute reduction in rough set theory is studied more deeply. Expand

A Fuzzy Approach to Some Set Approximation Operations

- Computer Science
- ICANN
- 2005

A fuzzy generalisation of two relation-based operations suitable for set approximations based on relationships between objects and their properties, which are based on similarities between objects. Expand

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