## Abstract

In this paper, we propose and axiomatically characterize residual contractions, a new kind of contraction operators for belief bases. We establish that the class of partial meet contractions is a strict subclass of the class of residual contractions. We identify an extra condition that may be added to the definition of residual contractions, which is such that the class of residual contractions that satisfy it coincides with the class of partial meet contractions. We investigate the interrelations in the sense of (strict) inclusion among the class of residual contractions and other classes of well known contraction operators for belief bases.

## Keywords

Belief change Belief bases Contraction Axiomatic characterizations Residual contractions Residuums## Notes

### Acknowledgements

We wish to thank Rineke Verbrugge (the Associated Editor handling this paper), and the two reviewers of JoLLI for their valuable comments on a previous version, which have contributed to a significant improvement. This work was partially supported by FCT - Fundação para a Ciência e a Tecnologia through Projects UID/MAT/04674/2019 (CIMA) and PTDC/CCI-COM/30990/2017.

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