Blog Archives

Merry Christmas

December 20, 2013
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Merry Christmas

Merry Christmas for all readers. Please enjoy my tree. codepart <- list(x0=0,y0=0,x1=0,y1=1,    branch1=NULL,branch2=NULL,extend=NULL,    lwd=1,depth=0,col='springgreen')par(mfrow=c(1,1),mar=c(5, 4, 4, 2) + 0.1)segplot <-...

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plotting y and log(y) in one figure

December 15, 2013
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plotting y and log(y) in one figure

Sometimes I have the desire to plot both on the linear and on the log scale. To save space just two figures is not my solution. I want to reuse the x-axis, legend, title. This post examines possibilities to do so with standard plot tools, lattice and g...

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Fukushima region radiation decrease

December 8, 2013
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Fukushima region radiation decrease

Fukushima is still a topic which gets headlines, and somewhere in a comment was a link to actual and historical radiation data: Fukushima prefecture radioactivity measurement map.  It takes a bit of time to load but then you have a map of the Fukushima region with current radiation levels at measurement stations. Somewhere on that website there is...

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JAGS model Fe concentration in rainwater including values below detection level

December 1, 2013
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JAGS model Fe concentration in rainwater including values below detection level

In my previous post I ignored the fact that some data are below the detection level. I would not know how to handle those in a mixed model from lme4 or nlme. However, JAGS can handle these values. Next to that I kept the usual independent variables, su...

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Dutch Rainwater Composition 1992-2011

November 24, 2013
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Dutch Rainwater Composition 1992-2011

Last week I examined rainwater composition 1992 to 2005. There is additional data, but National Institute for Public Health has changed equipment in 2005. This week I will add those data.DataData is in a number of spreadsheets. The scrip...

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Dutch Rainwater Composition 1992-2005.

November 17, 2013
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Dutch Rainwater Composition 1992-2005.

After reading Blog About Stats' Open Data Index Blog Post I decided to browse a bit in the Open Data Index. Choosing Netherlands and following Emission of Pollutants I ended on a page from National Institute for Public Health. The page&n...

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A small comparison of bio-equivalence calculations.

November 10, 2013
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Last week I looked at two-way cross-over studies and followed the example of Schütz (http://bebac.at/) in the analysis. Since the EU has its on opinions (Questions & Answers: Positions on specific questions addressed to the pharmacokinetics working party) and two example data sets, I was wondering how the various computations compared.Data There...

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Statistical aspects of two-way cross-over studies

November 3, 2013
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I ran into this presentation on Statistical aspects of two-way cross-over studies by Ing. Helmut Schütz (http://bebac.at). He presented some code and referred to the bear package. The bear package is menu driven, which is not my thing. I had to try and do that in R via other packages. The aim is to estimate if the...

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Symmetry in Williams designs

October 27, 2013
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Based on some comments I am looking at using symmetry to obtain Williams style designs. Symmetry allows reduction of the number of combinations examined hence faster calculation times. Two avenues are examined. Both work for a low number of treatments....

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Carry-over balanced designs for 8 treatments

October 19, 2013
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Those are Williams designs you might say, but it has become clear to me that Williams designs are just a subset of all carry-over balanced designs. Not through hard work of mine, comments by Apn on my previous post Creating Williams designs with e...

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