269 search results for "ANova"

The "golden age" of a football player

January 28, 2013
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The "golden age" of a football player

It's been some time since my last post on football. And we're talking about european soccer here. So I finally managed to write some functions which allow me to extract player stats from www.transfermarkt.de. The site tracks lots of stats in the world of soccer. For each player, there is information about the dominant foot, height, age, the estimated...

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Data science = failure of imagination

January 8, 2013
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From: http://www.r-bloggers.com/data-driven-science-is-a-failure-of-imagination/I think I like this distinction between Bayesian and Frequentist statistics: "we are nearly always ultimately curious about the Bayesian probability of the hypothesis ...

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Generation of E-Learning Exams in R for Moodle, OLAT, etc.

December 20, 2012
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Generation of E-Learning Exams in R for Moodle, OLAT, etc.

(Guest post by Achim Zeileis) Development of the R package exams for automatic generation of (statistical) exams in R started in 2006 and version 1 was published in JSS by Gr?n and Zeileis (2009). It was based on standalone Sweave exercises, that can be combined …Read more »

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Matrix Algebra Useful for Statistics

December 16, 2012
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Matrix Algebra Useful for Statistics

I was having a conversation with an acquaintance about courses that were particularly useful in our work. My forestry degree involved completing 50 compulsory + 10 elective† courses; if I had to choose courses that were influential and/or really useful they would be Operations Research, Economic Evaluation of Projects, Ecology, 3 Calculus and 2 Algebras.

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Clarifying a Previous Item Response Theory Link

December 11, 2012
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I wanted to thank those of you who have emailed and commented on my last post and its Link to Item Response Theory Presentations Using R.  In the Psychometrics Centre website, it is not until Topic 7 called Unidimensional IRT models for binar...

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The Hour of Hell of Every Morning – Commute Analysis, April to October 2012

November 19, 2012
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The Hour of Hell of Every Morning – Commute Analysis, April to October 2012

IntroductionSo a little while ago I quit my job.Well, actually, that sounds really negative. I'm told that when you are discussing large changes in your life, like finding a new career, relationship, or brand of diet soda, it's important to frame things positively.So let me rephrase that - I've left job I previously held to pursue other directions. Why?...

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Making sense of random effects

November 16, 2012
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Making sense of random effects

The other night in my office I got into a discussion with my office mate, the brilliant scientist / amazing skier Dr. Thor Veen about how to understand the random effect variance term in a mixed-effects model. Thor teaches the R statistics course here at UBC, and last night a student came to the office...

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GEE QIC update

November 15, 2012
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GEE QIC update

Here is improved code for calculating QIC from geeglm in geepack in R (original post). Let me know how it works. I haven’t tested it much, but is seems that QIC may select overparameterized models. In the code below, I … Continue reading →

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Trees with the rpart package

November 13, 2012
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Trees with the rpart package

What are trees? Trees (also called decision trees, recursive partitioning) are a simple yet powerful tool in predictive statistics. The idea is to split the covariable space into many partitions and to fit a constant model of the response variable in each partition. In case of regression, the mean...

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Exploring GAMs with Rosemary Hartman

November 9, 2012
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Exploring GAMs with Rosemary Hartman

Today at Davis R Users’ Group, Rosemary Hartman took us through her work in progress fitting general additive models to organism presence/absence data. Below is her presentation and script. You can get the original script and data here Also, check the comments below for some discussion of other options for this type of analysis, such as...

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