Blog Archives

Bayesian Wizardry for Muggles

July 11, 2014
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Monday, I will be giving the closing talk of the R in Insurance Conference, in London, on Bayesian Computations for Actuaries, as to be more specific, Getting into Bayesian Wizardry… (with the eyes of a muggle actuary). The animated version of the slides (since we will spend some time on MCMC algorithm, I thought that animated graphs could be...

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Statistics, and the Goldilocks Principle

June 26, 2014
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By the end of May, in Toronto, we had that great talk at the SSC by Jeff Rosenthal, on monte carlo techniques, and Jeff mention the name of “the Goldilocks principle” (it was in the contect of MCMC, and I did mention it in my talk in London on MCMC, when I discussed the value of the rejection rate...

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Conditional Distributions from some Elliptical Vectors

June 18, 2014
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Conditional Distributions from some Elliptical Vectors

This winter, in my ACT8595 course, I asked my students (that was some homework) to prove that it was possible to derive the conditional distribution when we have a Student-t random vector (and to get the analytical expression of the later). But before, let us recall a standard result about the Gaussian vector. If  is a Gaussian random vector, i.e. then  has a...

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Tukey and Mosteller’s Bulging Rule (and Ladder of Powers)

June 16, 2014
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Tukey and Mosteller’s Bulging Rule (and Ladder of Powers)

When discussing transformations in regression models, I usually briefly introduce the Box-Cox transform (see e.g. an old post on that topic) and I also mention local regressions and nonparametric estimators (see e.g. another post). But while I was working on my ACT6420 course (on predictive modeling, which is a VEE for the SOA), I read something about a “Ladder of...

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Box plot, Fisher’s style

June 4, 2014
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Box plot, Fisher’s style

In a recent issue of Significance, I discovered an interesting – and amuzing – figure, about some box & beard plot, in Dr Fisher’s casebook: Beard the statistician in his den. In French, the box plot (introduced by John Tukey, not George Box, as discussed in a previous post) is popular under the name boîte à moustaches (box with a...

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Your Life in Weeks

May 29, 2014
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Your Life in Weeks

This week, I discovered a picture on http://waitbutwhy.com/, which represent a (so-called) typical human life, in weeks, I found that interesting. But the first problem is that I don’t understand the limit, below: 90 years, that’s not the average life length. That’s not what you should expect to live when you get born. The second problem is that it cannot be...

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Allez les Bleus !

May 20, 2014
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Allez les Bleus !

In almost three weeks, the (FIFA) World Cup will start, in Brazil. I have to admit that I am not a big fan of soccer, so I will not talk to much about it. Actually, I wanted to talk about colors, and variations on some colors. For instance, there are a lot of blues. In order to visualize standard...

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Computational Actuarial Science

May 9, 2014
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Computational Actuarial Science

After some delay, the book Computational Actuarial Science with R is now annonced for July 2014. I don’t know if we will be able to get copies for the R in Insurance conference, in London, but I guess everyone is working on it. And kindly, CRC sent me the following flyer, with some reduction code to save 20% (when ordering...

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There is no “Too Big” Data, is there?

April 23, 2014
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There is no “Too Big” Data, is there?

A few years ago, a former classmate came back to me with a simple problem. He was working for some insurance company (and still is, don’t worry, chatting with me is not yet a reason for dismissal), and his problem was that their dataset was too large to run (standard) codes to get a regression, and some predictions. My...

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How Fast the Fastest Human Would Run 100m?

April 16, 2014
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How Fast the Fastest Human Would Run 100m?

Ethan Siegel wrote a post entitled The Math of the Fastest Human Alive five years ago, using regressions. An alternative is too use extreme value models (I wrote a post a long time ago on the maximum length of a tennis match using extreme value theory a few years ago). In 2009, John Einmahl and Sander Smeets wrote a great article...

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