I've just been reading Introduction to Scientific Programming and Simulation Using R by Owen Jones, Robert Maillardet, and Andrew Robinson. It seems like it would make a good introductory book for a course on, as the title suggests, scientific programm...
At this week's R clinic Frank Harrell will unveil the new rms (Regression Modeling Strategies) package that is a replacement for the R Design package. He will demonstrate the differences with Design, especially related to enhanced graphics for displaying effects in regression models. Frank will also discuss the implementation of quantile regression in rms. The rms package website has...
A multiple linear regression (MLR) model that describes a dependent variable y by independent variables x1, x2, ..., xp (p > 1) is expressed by the equation as follows, where the numbers α and βk (k = 1, 2, ..., p) are the parameter...
Any R user no matter what level of experience has had trouble finding the package or the function to do what you want to do and then figuring out how to use it. The sos package in R just made that a lot easier. First, fire up R, then install the sos package (don't omit the quotes): install.packages("sos") It'll ask you to...
Today it was once again time for the Chicago Half Marathon (which I have now been running in 2003, 2004, 2005, 2006, 2007 and 2008). Conditions were much much better than last year's very heavy rainfall---we were once again treated to a sunny and clear Chicago sky. It was however a little on the humid side and got...
Suppose you want a function to fit a neural network. What’s the best way to find it? Here are three steps that help to find the elusive function relatively quickly. First, use help.search("neural") or the shorthand ??neural. This will search the help files of installed packages for the word “neural”. Actually, fuzzy matching is used
Suppose you want a function to fit a neural network. What’s the best way to find it? Here are three steps that help to find the elusive function relatively quickly. First, use help.search("neural") or the shorthand ??neural. This will search the help...
Searching help pages of contributed packages just got easier with the release of the new sos package. This is a replacement for and substantial enhancement of the existing "RSiteSearch" package. To learn more about it, try vignette("sos") We hope...
In previous posts, I have shown the 1750-2008 global CO2 emission trends and the atmospheric CO2 concentrations at Mauna Loa, Hawaii. In this post, I compare annual CO2 emissions with annual changes in atmospheric CO2. The resulting chart shows the portion of CO2 emissions that remains in the atmosphere and the portion that 
Recently I wanted to plot an impulse response function with R and missed the MATLAB style stem plot for doing it. I couldn't find an R function for it with a quick Google search so I made my own. So here is the function and a small example:
#The function stem <- function(x,y,pch=16,linecol=1,clinecol=1,...){ if (missing(y)){ y = x ...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
