742 search results for "latex"

In three months, I’ll be in Vegas (trying to win against the house)

April 20, 2013
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In three months, I’ll be in Vegas (trying to win against the house)

In fact, I’m going there with my family and some friends, including two probabilists (I mean professionals, I am merely an amateur), with this incredible challenge: will I be able to convince  probabilists to go to play at the Casino? Actually, I also want to study them carefully, to understand how we should play optimally. For example, I hope...

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Le Monde puzzle [#817]

April 18, 2013
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Le Monde puzzle [#817]

The weekly Le Monde puzzle is (again) a permutation problem that can be rephrased as follows: Find where denotes the set of permutations on {0,…,10} and is defined modulo 11 . Same question for and for This is rather straightforward to code if one adopts a brute-force approach:: (where I

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Math symbols in R charts: a cheat sheet

April 15, 2013
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Math symbols in R charts: a cheat sheet

If you're creating a scientific graphic in the R language, there's a good chance you'll be wanting to include some mathematical symbols somewhere on the chart. You might want to use a symbol like μ as an axis label, annotate a curve with simple math like x2, or even put a complete equation like: in the title. You can...

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Simulating the Gambler’s Ruin

April 14, 2013
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Simulating the Gambler’s Ruin

The gambler’s ruin problem is one where a player has a probability p of winning  and probability q of losing. For example let’s take a skill game where the player x can beat player y with probability 0.6 by getting closer to target. The game play begins with player x being allotted 5 points and player y allotted 10

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Travis CI for R! (not yet)

April 12, 2013
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Travis CI for R! (not yet)

A few days ago I wrote about Travis CI, and was wondering if we could integrate the testing of R packages into this wonderful platform. A reader (Vincent Arel-Bundock) pointed out in the comments that Travis was running Ubuntu that allows you to install software packages at your will.

I took a look at the documentation, and realized...

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Reserving with negative increments in triangles

April 11, 2013
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Reserving with negative increments in triangles

A few months ago, I did published a post on negative values in triangles, and how to deal with them, when using a Poisson regression (the post was published in French). The idea was to use a translation technique: Fit a model not on ‘s but on , for some , Use that model to make predictions, and then...

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High Obesity levels found among fat-tailed distributions

April 11, 2013
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High Obesity levels found among fat-tailed distributions

In my never ending quest to find the perfect measure of tail fatness, I ran across this recent paper by Cooke, Nieboer, and Misiewicz. They created a measure called the “Obesity index.” Here’s how it works: Step 1: Sample four times from a distribution. The sample points should be independent and identically distributed (did your

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Dirichlet Process, Infinite Mixture Models, and Clustering

April 7, 2013
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Dirichlet Process, Infinite Mixture Models, and Clustering

The Dirichlet process provides a very interesting approach to understand group assignments and models for clustering effects.   Often time we encounter the k-means approach.  However, it is necessary to have a fixed number of clusters.  Often we encounter situations where we don’t know how many fixed clusters we need.  Suppose we’re trying to identify

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Subtraction Is Crazy

April 4, 2013
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Subtraction Is Crazy

I was re-reading Michael Murray’s explanation of cointegration:

and marvelling at the calculus.

Calculus blows my mind sometimes. Like, hey guess how much we can do with subtraction.

— protëa(@isomorphisms) March 28, 2013

Of course it’s not any subtraction. It’s subtracting a function from a shifted version of itself. Still doesn’t sound like a universal revolution.

(But of course the...

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Tables Are Like Cockroaches

April 3, 2013
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Tables Are Like Cockroaches

As much as I would like to completely replace all tables with beautiful, intuitive, and interactive charts, tables like cockroaches cannot be eliminated. Based on this very interesting discussion on the Perceptual Edge forum with source Exploring the Origins of Tables for Information Visualization, tables date back to 1850 BCE. The paper concludes with

As part of...

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