244 search results for "PCA"

Ce que je sais sur les séries temporelles (1/5)

September 9, 2013
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Ce que je sais sur les séries temporelles (1/5)

Ce que je sais sur les séries temporelles (1/5) En lisant la préface de Flore Vasseur à l'essai “le monde en 2030 vu par la CIA”, j'ai été très frappé par mon manque de culture macroéconomique. En effet, un essaiqui parle de...

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R for Ecologists: RLQ analysis (semi) explained

September 3, 2013
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R for Ecologists: RLQ analysis (semi) explained

I’ve been reading about RLQ analysis, also known as the fourth corner method, for analyzing relationships between environmental characteristics and species traits. I was interested because I thought I might be using RLQ analysis to answer a specific set of … Continue reading →

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R and Linear Algebra

August 29, 2013
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by Joseph Rickert I was recently looking through upcoming Coursera offerings and came across the course Coding the Matrix: Linear Algebra through Computer Science Applications taught by Philip Klein from Brown University. This looks like a fine course; but why use Python to teach linear algebra? I suppose this is a blind spot of mine: MATLAB I can see....

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The PISA2003lite package is released. Let’s explore!

August 20, 2013
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The PISA2003lite package is released. Let’s explore!

Today I’m going to show how to install PISA2003lite, what is inside and how to use this R package. Datasets from this package will be used to compare student performance in four math sub-areas across different countries. At the end of the day we will find out in which areas top performers from different countries

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Golf Scramble Simulation in R

August 14, 2013
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Golf Scramble Simulation in R

Golf Scramble Simulation Golf Scramble SimulationThis is a simulation of a standard best-ball golf scramble. Conventional wisdom has it that the best golfer (A) should hit last, the idea being that one of the lesser golfers may have a decent shot already so the...

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Orthogonal Partial Least Squares (OPLS) in R

July 28, 2013
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Orthogonal Partial Least Squares (OPLS) in R

I often need to analyze and model very wide data (variables >>>samples), and because of this I gravitate to robust yet relatively simple methods. In my opinion partial least squares (PLS) is a particular useful algorithm. Simply put, PLS is an extension of principal components analysis (PCA), a non-supervised  method to maximizing  variance explained in X,

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Simulation of Blackjack: the odds are not with you

July 19, 2013
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Simulation of Blackjack: the odds are not with you

I often want to simulate outcomes varying across a set of parameters. In order to accomplish this in an efficient manner I have coded up a little function that takes parameter vectors and produces results. First I will show how to set it up with some d...

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Oracle R Connector for Hadoop 2.2.0 released

July 19, 2013
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Oracle R Connector for Hadoop 2.2.0 is now available for download. The Oracle R Connector for Hadoop 2.x series has introduced numerous enhancements, which are highlighted in this article and summarized as follows: ORCH 2.0.0  ORCH 2.1.0  ORCH...

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Evaluating the Potential Incorporation of R into Research Methods Education in Psychology

July 17, 2013
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I was recently completing some professional development activities that required me to write a report on a self-chosen topic related to diversity in student backgrounds. I chose to use the opportunity to reflect on the potential for using R to teach psychology students research methods. I thought I'd share the report in case it interests anyone. Abstract...

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Analyse discriminante linéaire ou Regression logistique

July 10, 2013
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Analyse discriminante linéaire ou Regression logistique

Supposons que l'on dispose d'iris de Paris (en population >100khabts) et qu'on veuille pouvoir les classer selon leurs caractéristiques sociodémos : Population taux de chômage Etudiants CSP etc... Une fois, les iris classés, on se demande si l'on peut transporter cette typologie à une autre grande ville (Lyon) par exemple : Il faudrait alors pouvoir utiliser un modèle d'affectation des iris selon leurs caractéristiques respectives...

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