## Should simpler distributions have more prior probability?

D. R. Bickel, “Computable priors sharpened into Occam’s razors,” Working Paper, University of Ottawa, <hal-01423673>** **https://hal.archives-ouvertes.fr/hal-01423673 (2016). 2016 preprint

## Entropy sightings

Entropy and its many avatars. (English summary)

*J. Math. Soc. Japan*67 (2015), no. 4, 1845–1857.

94A17 (37A35 60-02 60K35 82B05)

The author, a chief architect of the theory of large deviations, chronicles several manifestations of entropy. It made appearances in the realms indicated by these section headings:

- Entropy and information theory
- Entropy and dynamical systems
- Relative entropy and large deviations
- Entropy and duality
- Log Sobolev inequality
- Gibbs states
- Interacting particle systems

The topics are connected whenever a concept introduced in one section is treated in more depth in a later section. In this way, relative entropy is seen to play a key role in large deviations, Gibbs states, and systems of interacting particles.

Less explicit connections are left to the reader’s enjoyment and education. For example, the relation between Boltzmann entropy and Shannon entropy in the information theory section is a special case both of Sanov’s theorem, presented in the section on large deviations, and of the relation of free energy and relative entropy, in the section on Gibbs states.

The paper ends with a tribute to Professor Kiyosi Itô.

Reviewed by David R. Bickel

**References**

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- J. D. Deuschel and D. W. Stroock, Large deviations, Pure and Appl. Math., 137, Academic Press, Inc., Boston, MA, 1989, xiv+307 pp. MR0997938
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## Undergraduate research project or internship

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## Statistics & biostatistics graduate studentships

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Intellectual curiosity and high mathematical aptitude are essential, as is the ability to quickly code and debug computer programs. Strong self motivation and good communication skills are also absolutely necessary. The following qualities are desirable but not required: coursework in bioinformatics, computer science, numerical methods, numerical analysis, software engineering, statistics, and/or biology; familiarly with BUGS, R, S-PLUS, C, Fortran, and/or LaTeX; experience with UNIX or Linux.

Canadians (by citizenship or permanent residency) are especially encouraged to apply, as are all exceptional students. To be considered, send a PDF CV that has your GPA and contact information of two references to dbickel@uOttawa.ca with either “MSc” or “PhD” and any specialization in the Subject line of the message and with a cover letter in the body of the message. Only those selected for further consideration will receive a response.

## Estimates of the local false discovery rate based on prior information: Application to GWAS

A. Karimnezhad and D. R. Bickel, “Incorporating prior knowledge about genetic variants into the analysis of genetic association data: An empirical Bayes approach,” Working Paper, University of Ottawa, deposited in uO Research at http://hdl.handle.net/10393/34889 (2016). 2016 preprint