Monthly Archives: September 2011

A Note on Antoniak’s Approximation for Dirichlet Processes

September 21, 2011
By
A Note on Antoniak’s Approximation for Dirichlet Processes

Antoniak's 1974 article titled Mixtures of Dirichlet Processes with Applications to Bayesian Nonparametric Problems (Annals of Statistics 2(6):1152-1174) is a fundamental work for most modern developments in this area. The article gives two expressions for the expected number of distinct values in a sample of size n, drawn from a Dirichlet process-distributed probability distribution with

Read more »

Solvency 2 WordCloud

September 21, 2011
By

Slow day at PSY headquarters: Click see wordleWe grabbed the Solvency II directive text from the EC website (© European Union, http://eur-lex.europa.eu/) and ran it through a couple of lines of R code to draw up wordcount frequencies. Then we plotted the text in Wordlehttp://www.wordle.net/show/wrdl/4111834/Solvency_2We're not convinced about the utility of WordClouds, but they look cool....

Read more »

Example 9.6: Model comparison plots (Completed)

September 21, 2011
By
Example 9.6: Model comparison plots (Completed)

We often work in settings where the data set has a lot of missing data-- some missingness in the (many) covariates, some in the main exposure of interest, and still more in the outcome. (Nick describes this as "job security for statisticians").Some ana...

Read more »

Density exploration and Wang-Landau algorithms [with R package]

September 21, 2011
By
Density exploration and Wang-Landau algorithms [with R package]

Hey, Since a new paper that I’ve co-written has appeared on arXiv, here is a quick post summarizing it. The paper is named: An Adaptive Interacting Wang-Landau Algorithm for Automatic Density Exploration and describes improvements over the Wang-Landau algorithm described … Continue reading →

Read more »

Climate Reference Network: package crn 1.0

September 20, 2011
By
Climate Reference Network:  package crn 1.0

I’ve just finished and uploaded another climate data package for R. This one focuses on  CRN the climate Reference Network Here is their home page   The package for now is really simple, but all of the packages  I’m building are getting simpler. In the end ( whenever that is ) I think I’ll end

Read more »

Children height and blood pressure z-scores

September 20, 2011
By
Children height and blood pressure z-scores

Following on from some of my earlier posts, this is purely about, hopefully, saving some other people some time in putting this together. Height z-scores are required to then calculate the blood pressure z-scores. The CDC (Center for Disease Control … Continue reading →

Read more »

Facebook like button in Graph Gallery

September 20, 2011
By
Facebook like button in Graph Gallery

I've added facebook like button in the home page of the R Graph Gallery and on each image page, i.e. this one which I "like".

Read more »

Recession forecasting III: A Better Naive Forecast

September 20, 2011
By
Recession forecasting III: A Better Naive Forecast

In Recession Forecasting Part II, I compared the accuracy of Hussman's recession forecasts to the accuracy of a naive forecast that assumed the current state of the recession variable would continue next month. An anonymous comment...

Read more »

Package ‘intergraph’ (1.1-0) released!

September 20, 2011
By

I just released the first official version of the ‘intergraph’ R package. With the functions provided in the current version (1.1-0) you can convert network data objects between classes ‘igraph’ and ‘network’. The package supports directed and undirected networks, and handles the node, tie, and network (graph) attributes. Mutliplex networks (i.e., with possibly multiple ties

Read more »

StackExchange and CrossValidated: An Epidemiologist’s Review

September 20, 2011
By
StackExchange and CrossValidated: An Epidemiologist’s Review

This seems like as good a day as any to review CrossValidated, and the whole StackExchange constellation of websites. It’s been a month since I joined, exactly, and today I also crossed the 1,000 reputation threshold on the site. So why not give my impressions of it? First, how I got there in the first

Read more »

Sponsors

Never miss an update!
Subscribe to R-bloggers to receive
e-mails with the latest R posts.
(You will not see this message again.)

Click here to close (This popup will not appear again)