The Ace code editor is an elegant, full-featured, browser-based code editor used in such products as RStudio’s IDE. We’re announcing a new R package called shinyAce (now available on CRAN) which integrates the Ace editor into the Shiny web framework. For those who may be unfamiliar, Shiny is ... [Read more...]

Last year, Brian Junker, Richard Patz, and I wrote an invited chapter for the (soon to be released) update of the classic text Handbook of Modern Item Response Theory (1996). The chapter is meant to be an update of the … Continue reading → [Read more...]

Version 1.2 of the RSiteCatalyst package to access the Adobe Analytics API is now available on CRAN! Changes include: Removed RCurl package dependency Changed argument order for GetAdminConsoleLog to avoid error when date not passed Return proper numeric type for metric columns Fixed bug in GetEVars function Added validate:true flag ... [Read more...]

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R-bloggers is offering an “R jobs” post, that will be published once every month (or other month). If you are interested in offering a job to be posted on r-bloggers, [Read more...]

There is no holy grail in trading instead there are strategies that work for a while or in a specific market environment. The role of the analyst is therefore twofold.  First find a good trading strategy, second find the right environment for this strategy. The present post focuses on the ... [Read more...]

Guest post by Vivian Zhang, original post. You can sign up for our Sunday Intensive beginner level R classes at NYC Data Science Academy meetup page or [Read more...]

We will continue the saga of the three-arm clinical trial that is giving the editors of the prestigious journal The Spleen a run for their money. While the polls are gathering digital dust, let’s see if we can direct this discussion to a more quantitative path. To do so, ... [Read more...]

After posting my analysis of the Enron email corpus, I realized that the regex patterns I set up to capture and filter out the cautionary/privacy messages at the bottoms of peoples emails were not working.  Let’s have a look at … Continue reading → [Read more...]

Today, I want to explain the commission’s functionality build in to Systematic Investor Toolbox(SIT) “share” back-test. At each re-balance time the capital is allocated given the weight such that For example, if weight is 100% (i.e. fully invested) and capital = $100 and price = $10 then The period return is equal ... [Read more...]

We're back from NYC after a very busy Strata + Hadoop World 2013 conference. Many thanks to all the friendly folks who dropped by the Revolution Analytics booth, attended Joe and Antonio's R and Hadoop tutorial, or simply came up to say hello during the event. It was a jam-packed conference, literally ... [Read more...]

This morning, I was working with Julie, a student of mine, coming from Rennes, on mortality tables. Actually, we work on genealogical datasets from a small region in Québec, and we can observe a lot of volatiliy. If I borrow one of her graph, we get something like Since ... [Read more...]

I've been exploring Jeff Gentry's twitteR package, which has a ton of great functionality for intereacting with twitter data in R. Today, I thought a bit about a problem I've noticed several times on twitter: users profiles are often only noisy signals of the content they tweet about! I decided ... [Read more...]

I archived and analyzed all Tweets containing #GI2013 from the recent Cold Spring Harbor Genome Informatics meeting, using my previously described code.Friday was the most Tweeted day. Perhaps this was due to Lior Pachter's excellent keynote, "Stories ... [Read more...]

Remember Gapminder, the animated motion chart popularised by Hans Rosling in his TED Talks and Joy of Stats TV programme? Well it’s back on TV this week in Don’t Panic – The Truth About Population, a compelling piece of OU/BBC co-produced stats theatre featuring Hans Rosling, and a ... [Read more...]

# The Poisson distribution has the interesting property that it# models outcomes from events that are independent and equally# likely to occur. The distribution takes only one parameter mu# which is equal to both the mean (expected number of events) #... [Read more...]

The complaint I hear most frequently about quantstrat is that it's slow, especially for large data.  Some of this slow performance is due to quantstrat treating all strategies as path-dependent by default.  Path dependence requires rules to b... [Read more...]

This is a problem I have encountered many times where the goal is to take a sample of spatial locations and apply constraints to the algorithm.  In addition to providing a pre-determined number of K clusters a fixed size of elements needs to be held constant within each cluster. An ... [Read more...]

We have previously written about creating interactive maps on the web from R, with the interactive maps on Github. See here, here, here, and here. A different approach is to use CartoDB, a freemium service with sql interface to your data tables that provides a map to visualize data in ... [Read more...]

on election days in the united states, the news media peppers its coverage with quick, dirty exit polls that allow them to make coarse statements like, "x% of demographic group y voted for candidate z."  the american national election studies are ... [Read more...]