Once we have chosen the model, we can continue acquiring spectra of new samples. Spectra is exported to a txt or csv file and we imported in R to be reprocessed.We use the function “predict” from the PLS package. I have done this with 20 new sample...

Expanding on a question on Stack Overflow I'll show how to make a stratified random sample of a certain size: d

As promised, this post is a bit more graphical, but I feel the need to stress the importance of the first few points in chapter 2 of the book (i.e. the difference between mean and average and why variance is meaningful). These are fundamental concepts for future work. The “pumpkin” ...

I’ve recently been working with methylation data; specifically, from the Illumina Infinium HumanMethylation450 bead chip. It’s a rather complex array which uses two types of probes to determine the methylation state of DNA at ~ 485 000 sites in the genome. The Bioconductor project has risen to the challenge with a (...

Macro analysis of Japanese trade in posts Japanese Trade and the Yen and Japan Trade by Geographic Region revealed some very interesting changes.  Since the Korean Won is so undervalued versus the Japanese Yen on a Purchasing Power Parity (PPP) ba...

This spring we have Rector Elections at Warsaw School of Economics. One of my collegues Tomasz Szapiro agreed to start in the elections. This induced me to write Shapley-Shubik Power Index calculation snippet in R.Rector elections in Warsaw School...

I used this idea posted on Stack Overflow to plug together a function for reading data from Google Docs spreadsheets into R. google_ss