Steven M. Pincus

Approximate entropy as a measure of system complexity.

Techniques to determine changing system complexity from data are evaluated. Convergence of a frequently used correlation dimension algorithm to a finite value does not necessari...

A regularity statistic for medical data analysis

Randomness and degrees of irregularity.

The fundamental question "Are sequential data random?" arises in myriad contexts, often with severe data length constraints. Furthermore, there is frequently a critical need to ...

Gender- and age-related differences in heart rate dynamics: Are women more complex than men?

Older males secrete luteinizing hormone and testosterone more irregularly, and jointly more asynchronously, than younger males

New statistical perspectives on the secretory patterns of both luteinizing hormone (LH) and testosterone (T) may prove useful in further understanding the aging process, and pos...

Heart rate control in normal and aborted-SIDS infants

Approximate entropy (ApEn), a mathematical formula quantifying regularity in data, was applied to heart rate data from normal and aborted-sudden infant death syndrome (SIDS) inf...

Approximate Entropy of Heart Rate as a Correlate of Postoperative Ventricular Dysfunction

These results suggest that changes in approximate entropy can distinguish between patients who sustained poor outcome and those who had an uncomplicated course.

Quantifying Complexity and Regularity of Neurobiological Systems

Complementary and Non-Coincident Increases in Heart Rate Variability and Irregularity during Fetal Development

1. Two distinct notions of variability have been defined to assess heart rate: deviation from a constant output (SD) and irregularity. One statistical measure of irregularity is...

Preliminary evidence for the evolution in complexity of heart rate dynamics during autonomic maturation in neonatal swine