Our 5th Cologne R user group meeting was the best attended meeting so far, with 20 members finding their way to the Institute of Sociology for two talks by Diego de Castillo on shiny and Stephan Holtmeier on cluster analysis, followed by beer and schnitzel at the Lux, a gastropub nearby.... [Read more...]

Some users had trouble installing the WRS package from R-Forge. Here’s a method that should work automatically and fail-safe: ?View Code RSPLUS# first: install dependent packages install.packages(c("MASS", "akima", "robustbase"))   # second: install suggested packages install.packages(c("cobs", "robust", "mgcv", "scatterplot3d", "quantreg", "rrcov", "lars", "pwr", "trimcluster", "... [Read more...]

In an earlier post, I introduced the golden section search method – a modification of the bisection method for numerical optimization that saves computation time by using the golden ratio to set its test points.  This post contains the R function that implements this method, the R functions that contain the 3 ... [Read more...]

Introduction The first algorithm that I learned for root-finding in my undergraduate numerical analysis class (MACM 316 at Simon Fraser University) was the bisection method.  It’s very intuitive and easy to implement in any programming language (I was using MATLAB at the time).  The bisection method can be easily adapted ... [Read more...]

Pretty Damn Quick (PDQ) performs a mean value analysis of queueing network models: mean values in; mean values out. By mean, I mean statistical mean or average. Mean input values include such queueing metrics as service times and arrival rates. These could be sample means. Mean output values include such ... [Read more...]

Enrollments are still open for the Level III Guerrilla Data Analysis Techniques class to be held during the week May 6—10. Early-bird discounts are still available. Enquire when you register. As usual, all classes are held at our lovely Larkspur... [Read more...]

These are materials for the first practical lesson of the Spatial Scale in Ecology course. All of the data and codes are available here. The class covered a 1.5h session. R code for the session is also at the end…Read more → [Read more...]

The Autoregressive Conditional Density (ACD) model of Hansen (1994) extended GARCH models to include time variation in the higher moment parameters. It was a somewhat natural extension to the premise of time variation in the conditional mean and variance, though it probably raised more questions than it, or subsequent research have ... [Read more...]

Still going through the book Veterinary Epidemiologic Research and today it’s chapter 18, modelling count and rate data. I’ll have a look at Poisson and negative binomial regressions in R. We use count regression when the outcome we are measuring is a count of number of times an event ... [Read more...]

[This article was first published on Learning Data Science , and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share [Read more...]

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I discovered the impressive data.table package more than a year ago. In order to learn how to use it, I …Continuar leyendo » [Read more...]

Using garch to learn a little about the distribution of returns. Previously There are posts on garch — in particular: A practical introduction to garch modeling The components garch model in the rugarch package garch and long tails There has also been discussion of the distribution of returns, including a satire ... [Read more...]

Data Analysis technologies such as t-test, ANOVA, regression, conjoint analysis, and factor analysis are widely used in the marketing research areas of A/B Testing, consumer preference analysis, market segmentation, product pricing, sales driver analysis, and sales forecast etc. Traditionally the analysis tools are mainly SPSS and SAS, however, the ... [Read more...]

not a survey, not even remotely current, the society of actuaries' medical large claims experience study (mlces) might be the best private health insurance claims data available to the public.  this data should be used to calibrate other data sets... [Read more...]

Thanks to a helpful SO-Answer I was able to download all CLC vector data (43 zip-files) programmatically:require(XML)path_to_files dir.create(path_to_files)setwd(path_to_files)doc urls # function to get zip file namesget_zip_name # function to plug into sapplydl_urls # download all zip-filessapply(urls, ... [Read more...]

The other day I came across the Empirical Quotes page on Mark Byran's blog. Some of his quotes related specifically to econometrics, and I thought I'd share a few others. That certainly doesn't mean that I agree with them all! "It is the preparation skill of the econometric chef that ... [Read more...]

Last year I sat on a couple of panels organised by I’m a Scientist’s Shane McCracken at various science communication conferences. A couple of days ago, I noticed Shane had popped up a post asking Who are you Twitter?, a quick review of a social media mapping exercise ... [Read more...]

Note: I started this post way back when the NCAA men's basketball tournament was going on, but didn't finish it until now. Since the NCAA Men's Basketball Tournament has moved to 64 teams, a 16 seed as never upset a 1 seed. You might be tempted to say ... [Read more...]

I recently made three posts regarding analysis of ordinal data. A post looking at all methods I could find in R, a post with an additional method and a post using JAGS. Common in all three was using the cheese data, a data set where... [Read more...]