Blog Archives

CrossValidated launched!

November 4, 2010
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CrossValidated launched!

The CrossValidated Q&A site is now out of beta and the new design and site name is live. New design The new design looks great, thanks to Jin Yang, our designer-in-residence. Note the normal density icon for accepted answers and the site icon depicting a 5-fold cross-validation (light green for the test set and dark

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Different results from different software

October 26, 2010
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I’ve had a few questions on this topic lately. Here is an email received today: I use Eviews to estimate time series, but I have been checking out R recently, and your Forecast package. I cannot understand why 2 similar equations in Eviews and R are giving different estimated output. Your insights will be invaluable

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How to avoid annoying a referee

October 22, 2010
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It’s not a good idea to annoy the referees of your paper. They make recommendations to the editor about your work and it is best to keep them happy. There is an interesting discussion on stats.stackexchange.com on this subject. This inspired my own list below. Explain what you’ve done clearly, avoiding unnecessary jargon. Don’t claim

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Happy World Statistics Day!

October 19, 2010
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The United Nations has declared today “World Statistics Day”. I’ve no idea what that means, or why we need a WSD. Perhaps it is because the date is 20.10.2010 (except in North America where it is 10.20.2010). But then, what happens from 2013 to 2099? And do we just forget the whole idea after 3112?

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Animated plots in R and LaTeX

October 12, 2010
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Animated plots in R and LaTeX

I like to use animated plots in my talks on functional time series, partly because it is the only way to really see what is going on with changes in the shapes of curves over time, and also because audiences love them! Here is how it is done. For LaTeX, you need to create every

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Why R is better than Excel for teaching statistics

October 4, 2010
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Why R is better than Excel for teaching statistics

This was the topic of a recent conversation on the Australian and New Zealand R mailing list. Here is an edited list of some of the comments made. R is free. R is well-documented. R runs (really well) on *nix as well as Windows and Mac OS. R is open-source. Trust in the R software

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The ARIMAX model muddle

October 4, 2010
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The ARIMAX model muddle

There is often confusion about how to include covariates in ARIMA models, and the presentation of the subject in various textbooks and in R help files has not helped the confusion. So I thought I’d give my take on the issue. To keep it simple, I will only describe non-seasonal ARIMA models although the ideas

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A texteditor for R

September 29, 2010
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A texteditor for R

I’ve been using RWinEdt for the last few years for all my R coding. But it no longer works with WinEdt 6.0 and no update has been forthcoming. Consequently, I’ve been looking around for something similar to take its place. This question has been asked before on StackOverflow and many suggestions were made including popular

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Forecasting with long seasonal periods

September 28, 2010
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Forecasting with long seasonal periods

I am often asked how to fit an ARIMA or ETS model with data having a long seasonal period such as 365 for daily data or 48 for half-hourly data. Generally, seasonal versions of ARIMA and ETS models are designed for shorter periods such as 12 for monthly data or 4 for quarterly data. The

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What should we call the stats Q&A site?

September 18, 2010
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What should we call the stats Q&A site?

The Q&A site at stats.stackexchange.com has been steaming ahead with loads of good questions and answers. We are currently trying to select a name and not many people have voted. Although we have more than 1300 users of the site, less than 40 people have currently voted on the name. There are four days left.

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