An updated version of TTR is now on CRAN. It fixes a couple bugs and includes a couple handy tweaks. Here's the full contents of the CHANGES file:TTR version 0.20-2 Changes from version 0.20-1NEW FEATURES:Added VWAP and VWMA (thanks to Brian Peterson...
A week or so ago I had my first experience using someone else’s cluster on Amazon EC2. EC2 is the Amazon Elastic Compute Cloud. Users set up a virtual computing platform that runs on Amazon’s servers “in the cloud.” Amazon EC2 is not just another cluster. EC2 allows the user to create a disk image containing an operating system...
Every Six months or so I like to update the Site Mapfor my blog jeromyanglim.blogspot.com. Thus, if you're new to the blog, The Site Map provides an overview of previous blog content organised by topic. RSS Feed: http://feeds.feedburner.com/jeromyang...
Every Six months or so I like to update the Site Mapfor my blog jeromyanglim.blogspot.com. Thus, if you're new to the blog, The Site Map provides an overview of previous blog content organised by topic. RSS Feed: http://feeds.feedburner.com/jeromyang...
Abilities of R for creating graphics is great, but one thing I always missed is the possibility of creating interactive plots and being able to look at graphs while changing one ore more parameters. I know that there is rggobi, but so far I always ran into problems with flexibility each time I wanted to 
“How to change the order of legend labels” is a question that gets asked relatively often on ggplot2 mailing list. A variation of this question is how to change the order of series in stacked bar/lineplots. While these two questions seem to be related, in fact they are separate as the legend is controlled by 
My parents and I made plans to visit San Jose and Saratoga on my grandmother’s birthday, March 19, since that is where she grew up. I randomly saw someone tweet about the ACM Data Mining Camp unconference that happened to be the next day, March 20, only a couple of miles from our hotel in Santa Clara. This was...
Tim O'Reilly's keynote talk at OSBC this evening was thought-provoking to say the least. The title of the talk was "The Real Open Source Opportunity", and the surprise for me was that he wasn't talking about Open Source software. Tim's insight, and it's a profound one, is that the next frontier for freedom and openness -- and indeed, the...
Hin-Tak Leung mailed me about a problem with certain malformed XML documents from FlowJo. There are namespace prefixes (prfx:nodeName) with no corresponding namespace declarations (xmlns:prefix=”uri”). How do we fix these? Well, the XML parser can read this but raises errors. We can do nice things to catch these errors and then post-process them. Then we 
I've been working mainly on abstract ABM, and I really don't need all that bells and whistles, and besides I've had some problems when trying to handle the relation between the real coordinate system and NetLogo own system. What I want is to use a GIS ...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
