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. 2016 Mar 13;374(2063):20150230.
doi: 10.1098/rsta.2015.0230.

What is information?†

Christoph Adami  1
Affiliations

What is information?†

Christoph Adami. Philos Trans A Math Phys Eng Sci. .

Abstract

Information is a precise concept that can be defined mathematically, but its relationship to what we call 'knowledge' is not always made clear. Furthermore, the concepts 'entropy' and 'information', while deeply related, are distinct and must be used with care, something that is not always achieved in the literature. In this elementary introduction, the concepts of entropy and information are laid out one by one, explained intuitively, but defined rigorously. I argue that a proper understanding of information in terms of prediction is key to a number of disciplines beyond engineering, such as physics and biology.

Keywords: Bayesian inference; entropy; information.

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Figures

Figure 1.
Figure 1.
A fair coin with entropy formula image bits. On the left, the outcome is ‘tails, quadrant II’, whereas the coin on the right landed as ‘heads, quadrant I’.
Figure 2.
Figure 2.
Entropy Venn diagram shows conditional and mutual entropies of two variables. Source: Wikimedia. (Online version in colour.)
See this image and copyright information in PMC

References

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    1. Adami C. 2012. The use of information theory in evolutionary biology. Ann. NY Acad. Sci. 1256, 49–65. ( 10.1111/j.1749-6632.2011.06422.x) - DOI - PubMed
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