An Information-Theoretical Method for Emotion Classification

  • Susana BrásEmail author
  • João M. Carvalho
  • Filipa Barros
  • Claúdia Figueiredo
  • Sandra C. Soares
  • Armando J. Pinho
Conference paper
Part of the IFMBE Proceedings book series (IFMBE, volume 76)


Identifying the emotion that someone is feeling will allow to improve the experience of the person interaction with environments, devices, and contents. Our body responds to events around us, by emotional responses, reflected in cognitive, behavioral and physiological dimensions. In the present work, we target the electrocardiogram (ECG) response as a mean to express emotions. Its processing is performed using information-theoretical measures, allowing true exploratory data mining. Participants recruited for the experiment watched three video sets in three different days, with a different emotion being induced in each day: fear, happiness, and neutral condition. The method is divided in: (1) conversion of the real-valued ECG record into a symbolic time-series; (2) relative compression of the symbolic representation of the ECG, using the symbolic ECG records stored in the database as a reference; (3) identification of the ECG record class, using a 1-NN (nearest neighbor) classifier. An accuracy of 90% was obtained. A posteriori analysis of the false negative results indicated that there was a relation between the relative dissimilarity measure and the self-reported emotions.


Emotion Affective computing Classification Data compression Kolmogorov complexity 



This work is funded by national funds, European Regional Development Fund, FSE through COMPETE2020, through FCT, in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19; and in the scope of the projects UID/CEC/00127/2013 (IEETA/UA), CMUP-ERI/FIA/0031/2013 (VR2Market). J. M. Carvalho acknowledges the Doctoral Grant from FCT, ref. SFRH/BD/136815/2018.

Conflict of Interest

None declared.


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Susana Brás
    • 1
    Email author
  • João M. Carvalho
    • 1
  • Filipa Barros
    • 3
    • 4
  • Claúdia Figueiredo
    • 2
  • Sandra C. Soares
    • 3
    • 4
    • 5
  • Armando J. Pinho
    • 1
  1. 1.IEETA, DETIUniversity of AveiroAveiroPortugal
  2. 2.GOVCOPPUniversity of CoimbraCoimbraPortugal
  3. 3.CINTESIS-UA, DEPUniversity of AveiroAveiroPortugal
  4. 4.William James Center for Research, DEPUniversity of AveiroAveiroPortugal
  5. 5.Department of Clinical Neurosciences, Division of PsychologyKarolinska InstituteStockholmSweden

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