Publications by Wingfeet

When should I change to snow tires in Netherlands

23.11.2014

The Royal Netherlands Meteorological Institute has weather information by day for a number of Dutch stations. In this post I want to use those data for a practical problem: when should I switch to winter tires? (or is that snow tires? In any case nails or metal studs are forbidden in Netherlands). Netherlands does not have laws prescr...

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Change in temperature in Netherlands over the last century

30.11.2014

I read a post ‘race for the warmest year’ at sargasso.nl. They used a plot, originating from Ed Hawkins to see how 2014 progressed to be warmest year. Obviously I wanted to make the same plot using R. In addition, I wondered which parts of the year had most increased in temperature.DataSimilar to last week, data are acquired from ...

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SAS PROC MCMC in R: Nonlinear Poisson Regression Models

06.12.2014

In exercise 61.1 the problem is that the model has bad mixing. In the SAS manual the mixing is demonstrated after which a modified distribution is used to fix the model.In this post the same problem is tackled in R; MCMCpack, RJags, RStan and LaplaceDemon. MCMCpack has quite some mixing problems, RStan seems to do best.DataTo quote th...

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Monthly Weather in Netherlands

14.12.2014

When I downloaded the KNMI meteorological data, the intention was to do something which takes more than just the computers memory. While it is clearly not big data, at the very least 100 years of daily data is not small either. So I took along a load of extra variables to see what trouble I would run into. I did not run out of memory,...

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Merry Christmas

21.12.2014

Based on The DO loop, since I wanted a fractal Christmas tree and there is no point in inventing what has been made already. Besides, this is not the first time this year that I used R to do what has been done in SAS.Code# http://blogs.sas.com/content/iml/2012/12/14/a-fractal-christmas-tree/# Each row is a 2×2 linear transformation ...

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A time series contest attempt

28.12.2014

I saw the post a time series contest on Rob J Hyndman’s blog. Since I am still wanting to play around with some bigger data sets, so I went to the source website https://drive.google.com/folderview?id=0BxmzB6Xm7Ga1MGxsdlMxbGllZnM&usp=sharing and got myself the data. One warning, if you are reading this to know how to get close to ...

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Capital in the Netherlands, 2006-2013

04.01.2015

I guess most people have heard of Piketty and his book capital in the twenty-First century. I don’t have that book, but the media attention has made me wonder if I could see any trends in Dutch public data. As I progressed with this post, I have concluded that these data could not tell me much about longer term trends, however, one ...

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Multivariate analysis of death rate on the map of Europe

11.01.2015

Eurostat has information on death rates by cause and NUTS 2 region. I am trying to get this visually displayed on the map. To get there I map all causes to three dimensions via a principal components analysis. These three dimensions are subsequently translated in RGB colors and placed in the map of Europe.DataDeath rates are from Euro...

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SAS PROC MCMC example in R: Logistic Regression Random-Effects Model

18.01.2015

In this post I will run SAS example Logistic Regression Random-Effects Model in four R based solutions; Jags, STAN, MCMCpack and LaplacesDemon. To quote the SAS manual: ‘The data are taken from Crowder (1978). The Seeds data set is a 2 x 2 factorial layout, with two types of seeds, O. aegyptiaca 75 and O. aegyptiaca 73, and two ro...

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Odds, odds ratio, language and intuition

25.01.2015

I was reading a statistics book the other day. I am at the beginning. In this section I read ‘(we) report results as odds ratios, which is more intuitive’. I must have read sentences stating this any number of times. But I don’t agree.It may be my background. My mother tongue is Dutch, which does not have a word for odds. Hence ...

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