The international R User Conference useR! 2012 will be held June 12-15 at Vanderbilt University in Nashville, Tennessee, USA, with a pre-conference full-day course offered on June 11. Participants are encouraged to submit a one-page abstract for oral or poster presentation at the conference. Half-day tutorials will be held in the morning and afternoon of June 12th. For tutorials,...
Monthly Archives: December 2011
ML-Class Ex 7 – kMeans clustering
The K-means algorithm is a method to automatically cluster similar data examples together. The intuition behind K-means is an iterative procedure that starts by guessing the initial centroids, and then refines this guess by repeatedly assigning examples to their closest centroids and then recomputing the centroids based on the assignments. Read more »
Recology is 1 yr old
This blog has lasted a whole year already. Thanks for reading and commenting. There are a couple of announcements: Less blogging: I hope to put in many more years blogging here, but in full disclosure I am blogging for Journal of Ecology now, ...
Recology is 1 yr old
This blog has lasted a whole year already. Thanks for reading and commenting. There are a couple of announcements: Less blogging: I hope to put in many more years blogging here, but in full disclosure I am blogging for Journal of Ecology now, ...
Recology is 1 yr old…
This blog has lasted a whole year already. Thanks for reading and commenting. There are a couple of announcements:Less blogging: I hope to put in many more years blogging here, but in full disclosure, I am blogging for Journal of Ecology no...
A Christmas Miracle
Data files on 407 banks, between the dates of 2007 to 2009, on the daily borrowing with the US Federal Reserve bank. The data sets are available from Bloomberg at this address data This is an unprecedented look into the day-to-day transactions of ...
Programming traps when using "sample"
Standard sample function works differently when it gets single element integer vector as opposed to longer vectors. This can lead to unexpected bugs in R code.Several times I had a problem with code similar to one given here:for (i in 1:4) {&...
Norman Nie on two big problems with Big Data
Revolution Analytics CEO Norman Nie sat down with Cassimir Medford from Business Agility to talk about the problems business today face with respect to Big Data. The two big problems identified: finding adequately trained personnel and locating the right tools. Norman traces the problem of finding skilled practitioners to work with Big Data to the US educational system: The...
Portfolio Optimization in R, Part 4
This post will conclude the portfolio optimization series. In this post, we will construct a trading strategy based on portfolio optimization and test the results against the CAPM market portfolio as well as another strategy.It is worth reiterati...
googleVis 0.2.13: new stepped area chart and improved geo charts
On 7th December Google published a new version of their Visualisation API. The new version adds a new chart type: Stepped Area Chart and provides improvements to Geo Chart. Now Geo Chart has similar functionality to Geo Map, but while Geo Map requires ...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
