Author: Luis (Page 62 of 71)

On the (statistical) road, workshops and R

2011-12-03 / Luis

Things have been a bit quiet at Quantum Forest during the last ten days. Last Monday (Sunday for most readers) I flew to Australia to attend a couple of one-day workshops; one on spatial analysis (in Sydney) and another one on modern applications of linear mixed models (in Wollongong). This will be followed by attending The International Biometric Society Australasian Region Conference in Kiama.

I would like to comment on the workshops to look for commonalities and differences. First, both workshops heavily relied on R, supporting the idea that if you want to reach a lot of people and get them using your ideas, R is pretty much the vehicle to do so. It is almost trivial to get people to install R and RStudio before the workshop so they are ready to go. “Almost” because you have to count on someone having a bizarre software configuration or draconian security policies for their computer.
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Portrait Jorge Luis Borges in 1951, by Grete Stern — Jorge Luis Borges in 1951, by Grete Stern

Solomon saith

2011-11-25 / Luis

Solomon saith, There is no new thing upon the earth. So that as Plato had an imagination, that all knowledge was but remembrance; so Solomon giveth his sentence, That all novelty is but oblivion.
Francis Bacon: Essays, LVIII quoted by Jorge Luis Borges in The Immortal (1949).

Gratuitous image: Tree spread on metal frame to provide shade in a plaza, Lisbon, Portugal. Some days I would love to have a coffee there without computer, just watching the world pass by. (Photo: Luis).

If you are writing a book on Bayesian statistics

2011-11-24 / Luis

This post is somewhat marginal to R in that there are several statistical systems that could be used to tackle the problem. Bayesian statistics is one of those topics that I would like to understand better, much better, in fact. Unfortunately, I struggle to get the time to attend courses on the topic between running my own lectures, research and travel; there are always books, of course.

No one would ever conceive

2011-11-23 / Luis

I believe that no one who is familiar, either with mathematical advances in other fields, or with the range of special biological conditions to be considered, would ever conceive that everything could be summed up in a single mathematical formula, however complex.
R.A. Fisher (1932) quoted in the preface to Foundations of Mathematical Genetics by A.W.F. Edwards (1976).

Generic radiata pine in Northern Tasmania.

Do we need to deal with ‘big data’ in R?

2011-11-22 / Luis

David Smith at the Revolutions blog posted a nice presentation on “big data” (oh, how I dislike that term). It is a nice piece of work and the Revolution guys managed to process a large amount of records, starting with a download of 70GB and ending up with a series of linear regressions.

I’ve spent the last two weeks traveling (including a visit to the trial below) and finishing marking for the semester, which has somewhat affected my perception on dealing with large amounts of data. The thing is that dealing with hotel internet caps (100MB) or even with my lowly home connection monthly cap (5GB) does get one thinking… Would I spend several months of internet connection just downloading data so I could graph and plot some regression lines for 110 data points? Or does it make sense to run a linear regression with two predictors using 100 million records?