Unbiased entropy estimates in stress: a parameter study

Aleksandar Boskovic, Tatjana Loncar-Turukalo, Olivera Sarenac, Nina Japundzic-Zigon, Dragana Bajic

Research output: Contribution to journalArticle (Academic Journal)peer-review

14 Citations (Scopus)


This study proposes a method for obtaining a stable working point that enables the unbiased estimates of the approximate entropy and the sample entropy. Pattern length, normalized threshold, time delay and tines series length are levels of freedom that are considered. Pulse interval signals used for the experiment are recorded from laboratory animals with different likelihood of developing cardiovascular disease--normal and borderline hypertensive rats--exposed to the acute and to the chronic stress. It is shown that the threshold level is the major source of the instability, and that the generally accepted and widely used methods for a threshold choice may lead to an incorrect psychological interpretation. A method for the threshold level correction is proposed.

Original languageEnglish
Pages (from-to)667-79
Number of pages13
JournalComputers in Biology and Medicine
Issue number6
Publication statusPublished - Jun 2012


  • Animals
  • Computational Biology
  • Entropy
  • Hypertension
  • Male
  • Models, Biological
  • ROC Curve
  • Rats
  • Rats, Inbred SHR
  • Rats, Wistar
  • Stress, Physiological
  • Journal Article
  • Research Support, Non-U.S. Gov't


Dive into the research topics of 'Unbiased entropy estimates in stress: a parameter study'. Together they form a unique fingerprint.

Cite this