Models vs. Experts #4: Electrocardiogram

Models vs. Experts #4: Electrocardiogram

May 8, 2013 Behavioral Finance
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(Last Updated On: January 18, 2017)

Performance of the computer and physician in the analysis of the electrocardiogram

  • Caceres, C. A., & Hochberg, H. H.
  • American Heart Journal, 79, 439-443
  • A version of the paper can be found here.
  • Want a summary of academic papers with alpha? Check out our free Academic Alpha Database!


A sustained level of measurement accuracy possible by computers is not often achieved by physicians  Similarly, once programmed to repeat interrelation of measurements in a set of criteria, the computer is far more reliable than man, as the machine system always follows designated logic without subjectivity.

Why Humans Disagree?

In the context of electrocardiograms the arguments in favor of computer use appear overwhelming and the profession has moved in the direction of computer analysis. This paper is not directly engaging in the model vs. expert debate. This paper tries to understand WHY humans disagree with computer outputs in the context of electrocardiogram outputs.

Technicians feed the computer recordings. Some recordings are noisy and contain error (poor technical recordings) and some are clean (good technical recordings). In this study, the authors disregard “poor technical recordings” because this is a case of “garbage in, garbage out.” The focus throughout is on good technical recordings, where the computer is known to perform at a very high level of accuracy.

Among good recordings:

  1. Humans only agree with the computer 58% of the time
  2. Humans disagree 42% of the time
    1. 13% due to physician error (they are simply wrong)
    2. 13% due to “criteria” differences. The computer isn’t wrong, the human isn’t wrong, but it is unclear what the standard is
    3. 10% due to imprecise criteria (computer wasn’t programmed correctly)
  1. 6% general computer error
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About the Author

Wesley R. Gray, Ph.D.

After serving as a Captain in the United States Marine Corps, Dr. Gray earned a PhD, and worked as a finance professor at Drexel University. Dr. Gray’s interest in bridging the research gap between academia and industry led him to found Alpha Architect, an asset management that delivers affordable active exposures for tax-sensitive investors. Dr. Gray has published four books and a number of academic articles. Wes is a regular contributor to multiple industry outlets, to include the following: Wall Street Journal, Forbes,, and the CFA Institute. Dr. Gray earned an MBA and a PhD in finance from the University of Chicago and graduated magna cum laude with a BS from The Wharton School of the University of Pennsylvania.