The MAPE (mean absolute percentage error) is a popular measure for forecast accuracy and is defined as where denotes an observation and denotes its forecast, and the mean is taken over . Armstrong (1985, p.348) was the first (to my knowledge) to point out the asymmetry of the MAPE saying that “it has a bias favoring estimates...
(Generalized) Linear models make some strong assumptions concerning the data structure: Independance of each data points Correct distribution of the residuals Correct specification of the variance structure Linear relationship...
As I mentioned in my previous blog post, Government of India have started an Open Data Portal for making various data public. Most of the data-sets on the portal...
I recently posted on the addition of ageKeyPlot() to the FSA package for visualizing age-length keys. Since that post, I have added one more type of plot as illustrated...
I enjoyed talking to University of Alabama students this morning about wealth, skill, and luck. I tried to synthesize a whole lot of research into something meaningful. Of course,...
by Daniel Hanson Last time, we looked at the four-parameter Generalized Lambda Distribution, as a method of incorporating skew and kurtosis into an estimated distribution of market returns, and...
GoogleVis 0.5.1 was released on CRAN yesterday. New Features New functions gvisSankey, gvisAnnotationChart, gvisHistogram,gvisCalendar and gvisTimeline to support the new Google charts of the same names (without 'gvis'). New...
This is the third in my series of three posts on my package freqparcoord with Yingkang Xie. (My next post after this will show how to use R to...
This post shares the video from the talk presented in 2014 by Eu Jin Lok on mining tweets with R presented at Melbourne R Users. Twitter is currently ranked...
Yesterday's release of RcppBDT 0.2.3 lead to an odd build error. If one used at the same time a 32-bit OS, a compiler as recent as g++ 4.7 and the Boost...
A new Task View on CRAN will be of anyone who needs to connect R with Web-based applications. The Web Technologies and Services Task View lists R functions and...
Kevin Cartier writes: I’ve been happily using R for a number of years now and recently came across Stan. Looks big and powerful, so I’d like to pick an...
Rick Wicklin showed how to make a Hilbert matrix in SAS/IML. Rick has a nice discussion of these matrices and why they might be interesting; the value of...
Check out PDF for Equations And Code to run yourselfIntroduction: “This Time is different” by Reinhart and Rogoff is an empirical history of financial crises and panics....
(This article was first published on Econometrics by Simulation, and kindly contributed to R-bloggers) The Homeless Econometrician: Black Box SoftwareChoosing to go open source is a big deal. It...
We've received a number of questions from our users about dealing with the finer details of data sources on the web. Whether you're reading data from local storage such...
The 'regex' family of languages and commands is used for manipulating text strings. More specifically, regular expressions are typically used for finding specific patterns of characters and replacing them with others....
A new release of the RcppBDT package is now on CRAN.Several new modules were added; the package can now work on dates, date durations, "ptime" (aka posix time), and...
A few days ago, the Centers for Medicare and Medicaid Services (CMS) released some unprecedented data on the US healthcare system. The data consists of 9 million rows...
Social Science Goes R: Weighted Survey Data Survey Data: Computing Your Own Weights...
ggplot2 tries to make it super easy to add country or state borders to your map, and for the most part it works great as long as you include...
There's so much being written about R these days, and justifiably so. If you use R for your econometrics, you should also keep in mind that its applicability...
ChIPpeakAnno WAS the only one R package for ChIP peak annotation. I used it for annotating peak in my recent study.I found it does not consider the strand...
The next stage in my earthquake analysis project is to partition the events into groups with epicentre over land or water. Since our existing catalog contains the latitude and...
I love massive open online courses such as provided on Coursera and edX. So I enrolled in the Data Analysis for Genomics course on edX. I am not alone...
Originally posted on Rolling Your Rs:In this article I discuss a general approach for Geocoding a location from within R, processing XML reports, and using R packages to...
The new version of WrightMap (Ancillary Antelope) is now available on CRAN.Remember that you can visit the package tutorials on our website.This new version...
Lately, I have been interested in methods related to age-length keys. One aspect of this interest has been in visualizing age-length keys. I had seen various visualizations in publications...
Plotly: collaborative, publication-quality graphing. 
