Cross-validation and Bayesian estimation of tuning parameters

December 10, 2013
By
Cross-validation and Bayesian estimation of tuning parameters

Ilya Lipkovich writes: I read with great interest your 2008 paper [with Aleks Jakulin, Grazia Pittau, and Yu-Sung Su] on weakly informative priors for logistic regression and also followed an interesting discussion on your blog. This discussion was within Bayesian community in relation to the validity of priors. However i would like to approach it […]The post Cross-validation and Bayesian estimation of tuning parameters appeared first on Statistical Modeling, Causal…

Read more »

Next Kölner R User Meeting: 13 December 2013

December 10, 2013
By
Next Kölner R User Meeting: 13 December 2013

Quick reminder: The next Cologne R user group meeting is scheduled for this Friday, 13 December 2013. We are delighted to welcome:Matt Dowle and Arun Srinivasan: Introduction to data.tableThomas Rahlf: Book presentation - Datendesign mit RFurther deta...

Read more »

Book Review: Learning Geospatial Analysis with Python by Joel Lawhead

December 10, 2013
By
Book Review: Learning Geospatial Analysis with Python by Joel Lawhead

I decided to read this book since I've been doing maps using R. Hence it is better to learn the literature and science behind mapping and how to do a proper analysis on it. In addition, I would like to see what Python can offer in this discipline.The b...

Read more »

eeptools 0.3 Released!

December 10, 2013
By

Version 0.3 of my R package of miscellaneous code has been released, this time with substantial contributions from Jason Becker via GitHub. Progress continues toward the ultimate goal for eeptools to "make it easier for administrators at stat...

Read more »

To Cluster or Not to Cluster – That is the Question

December 10, 2013
By

Several very prominent econometricians have fallen on either side of thisquestion, typically they are concerned that the number of clusters issmall and the size in each cluster is large.  One camp argues that theonly reasonable way of deriving con...

Read more »

Harvard gives new meaning to meritocracy

December 10, 2013
By

Due to the fastidious efforts of Professor Harvey Mansfield, Harvard has confirmed the legend that "the hard part is to get in". Not only does it appear impossible to flunk out but according to the new revelation (link), the median grade given is A- and "the most frequently awarded grade at Harvard College is actually a straight A". The last sentence can be interpreted in two ways. If "straight A"…

Read more »

Biostar Tutorial: Cheat sheet for one-based vs zero-based coordinate systems

December 9, 2013
By
Biostar Tutorial: Cheat sheet for one-based vs zero-based coordinate systems

Obi Griffith over at Biostar put together this excellent cheat sheet for dealing with one-based and zero-based genomic coordinate systems. The cheat sheet visually explains the difference between zero and one-based coordinate systems, as well as how to...

Read more »

How to model distributions that have outliers in one direction

December 9, 2013
By

Shravan writes: I have a problem very similar to the one presented chapter 6 of BDA, the speed of light example. You use the distribution of the minimum scores from the posterior predictive distribution, show that it’s not realistic given the data, and suggest that an asymmetric contaminated normal distribution or a symmetric long-tailed distribution […]The post How to model distributions that have outliers in one direction appeared first on…

Read more »

The importance of a proper scale

December 9, 2013
By
The importance of a proper scale

Business Insider (link) highlighted a map showing childhood food insecurity across the 50 states, with the data coming from a report by Brookings. This is a nice map. I like the tones of the chosen colors although the colors are...

Read more »

Last (talk before) Christmas

December 9, 2013
By
Last (talk before) Christmas

OK, so first things first. I've always: 1) been a huge fan of the reindeer hat; 2) wondered what George Michael had actually given as a present to the other guy (if anything!). On a much less serious note, as I managed to get (nearly com...

Read more »

Comparing Predictive Accuracy, Twenty Years Later

December 9, 2013
By

I have now posted the final pre-meeting draft of the "Use and Abuse" paper (well, more-or-less "final").I'll present it as the JBES Lecture, January 2014 ASSA meetings, Philadelphia. Please join if you're around. It's Friday January 3, 2:30, ...

Read more »

Interpreting PROC IML error messages: Matrices do not conform to the operation

December 9, 2013
By
Interpreting PROC IML error messages: Matrices do not conform to the operation

When learning a new language, it is important to learn to interpret error messages that come from the language's parser or compiler. Three years ago I blogged about how to interpret SAS/IML error messages. However, many questions have been posted to the SAS/IML Support Community that indicate that some people [...]

Read more »

Visualizing data analysis pipelines using NetworkX

December 8, 2013
By
Visualizing data analysis pipelines using NetworkX

In complicated data analysis pipelines and scientific workflows, it's often difficult to keep track of which tasks have to be performed before others. Even with informal forms of documentation (my personal favorite is 'notes.txt'), as the size of a project grows, and more dependencies are introduced, a formal documentation process has to be put in »more

Read more »

Update on Bayes Pharma 2014

December 8, 2013
By
Update on Bayes Pharma 2014

This is the logo for the 2014 edition of Bayes Pharma. Very soon we'll advertise the programme and more details $-$ I'll post about it as well. At the moment, we're finalising the plan but I think we've decided to structure the workshops in this w...

Read more »

Sentence Drawing: Function vs. Art

December 8, 2013
By
Sentence Drawing: Function vs. Art

I recently was reading the book “Functional Art” and came across the work of Stefanie Posavec. Her Sentence Drawings (click here to see and click here to learn) caught my attention. Here is a ggplot2 rendition: From what I understand … Continue reading →

Read more »

The never-ending (and often productive) race between theory and practice

December 8, 2013
By
The never-ending (and often productive) race between theory and practice

Commenter Wonks Anonymous writes: After the recent EconNobel announcement I decided to check Dimensional’s Fama-French blog to see if it had much new content recently, and while it was dissapointingly sparse it did have an interesting bit where Fama linked to the best advice he’d ever gotten, from his statistics professor Harry Roberts: With formal […]The post The never-ending (and often productive) race between theory and practice appeared first on…

Read more »

amazonly associated thanks (& warnin’)

December 8, 2013
By
amazonly associated thanks (& warnin’)

Following a now well-established pattern, let me (re)warn (the few) unwary ‘Og readers that the links to Amazon.com and to Amazon.fr found on this blog are actually susceptible to earn me a monetary gain [from 4% to 8% on the sales] if a purchase is made by the reader in the 24 hours following the […]

Read more »

Fukushima region radiation decrease

December 8, 2013
By
Fukushima region radiation decrease

Fukushima is still a topic which gets headlines, and somewhere in a comment was a link to actual and historical radiation data: Fukushima prefecture radioactivity measurement map.  It takes a bit of time to load but then you have a map of the...

Read more »

If I could’ve done it all over again

December 7, 2013
By

I’d've given this blog the name, tl;dr. Too late to change it now, though, I think! The post If I could’ve done it all over again appeared first on Statistical Modeling, Causal Inference, and Social Science.

Read more »

An Animation of the t Distribution as a Mixture of Normals

December 7, 2013
By
An Animation of the t Distribution as a Mixture of Normals

You’ve probably heard about the t distribution. One good use for this distribution is as an alternative to the normal distribution that is more robust against outliers. But where does the t distribution come from? One intuitive characterization of ...

Read more »

Weekend Reading: F-Squared

December 7, 2013
By
Weekend Reading: F-Squared

Mebane Faber posted another interesting blog post: Building a Simple Sector Rotation on Momentum and Trend that caught my interest. Today I want to show how you can test such strategy using the Systematic Investor Toolbox: Mebane thank you very much for sharing your great ideas. I would encourage readers to play with this strategy […]

Read more »

Le Monde puzzle [#843]

December 6, 2013
By
Le Monde puzzle [#843]

A Le Monde mathematical puzzle of moderate difficulty: How many binary quintuplets (a,b,c,d,e) can be found such that any pair of quintuplets differs by at least two digits? I solved it by the following R code that iteratively eliminates quintuplets that are not different enough from the first ones, for a random order of the […]

Read more »

Three Quick and Simple Data Cleaning Helper Functions (December 2013)

December 6, 2013
By

As I go about cleaning and merging data sets with R I often end up creating and using simple functions over and over. When this happens, I stick them in the DataCombine package. This makes it easier for me to remember how to do an operation and others ...

Read more »


Subscribe

Email:

  Subscribe