Andrew Gelman linked to this great reporting by Reuters on U.S. healthcare economics. It's a must-read. Be patient, and read through to the end even though it's a long piece. Andrew cites statistician Don Berry who explains what "lead time bias" is, and why survival time is always the wrong metric to use in evaluating health outcomes. Survival time is the time from diagnosis to death. By doing more screening…
We had 28 class periods, so I wrote an exam with an approximate correspondence of one question per class. Rather than dumping the exam in your lap all at once, I’ll post the questions once per day. Then each day I’ll post the answer to yesterday’s questions. So it will be 29 days in all. [...]
We had 28 class periods, so I wrote an exam with an approximate correspondence of one question per class. Rather than dumping the exam in your lap all at once, I’ll post the questions once per day. Then each day I’ll post the answer to yesterday’s questions. So it will be 29 days in all. [...]
San Diego-based start-up Easel.ly [easel.ly] is offering a beta service that allows lay people to design and implement their own "infographics" via an online editor. The user-based customization of infographics seems to be the next phase after the aut...
In part 2, we saw that adding a volatility filter to a single instrument test did little to improve performance or risk adjusted returns. How will the volatility filter impact a multiple instrument portfolio? In part 3 of the follow up, I will evaluate the impact of the volatility filter on a multiple instrument test. … Continue reading →
Graphs that are not drawn to scale mislead the reader. This post shows another example of a graph where the visual representation of the numbers is not proportional to the numbers themselves.
I received the following email the other day: Dear Dr. Gelman, I am emailing to let you know that your accepted article for Economic Inquiry will be published in print in the forthcoming April 2012 Issue. You will be receiving hard copies of the journal from Wiley-Blackwell for distribution to yourself and the Co Authors. [...]
Thanks to everyone for the feedback on my post on knowing when someone is good at data analysis. A couple people suggested I take a look here for a few people who have proven they’re good at data analysis. I think that’s a great idea and a ...
This time from Bernard Fraga and Eitan Hersh. Once you think about it, it’s hard to imagine any nonzero treatment effects that don’t vary. I’m glad to see this area of research becoming more prominent. (Here‘s a discussion of another political science example, also of voter turnout, from a few years ago, from Avi Feller [...]
Learning to use a data analysis tool well takes significant effort, so people tend to continue using the tool they learned in college for much of their careers. As a result, the software used by professors and their students is … Continue reading →
The series of infographics titled "The Iranian Internet" [this-is-maral.com] by master student Maral Pourkazemi combines an aesthetic sense of (greyscale) infographics with the serious topic of international politics. Maral designed six different co...
The rushing game is slowly disappearing. Heave That Sucker When it doubt, chunk the pigskin. Whether you like it or not, NFL (National Football League) teams are relying upon passing more and more. Looking at the above chart, the average p...
DealBook: Glaxo to Make Hostile Bid for Human Genome Sciences: On the heals of the failed Illumina deal, another bare-knuckled brawl. GlaxoSmithKline plans to take its bid for Human Genome Sciences directly to shareholders this week, after being rejec...
From August 1990. It was in the form of a note sent to all the people in the statistics group of Bell Labs, where I’d worked that summer. To all: Here’s the abstract of the work I’ve done this summer. It’s stored in the file, /fs5/gelman/abstract.bell, and copies of the Figures 1-3 are on Trevor’s [...]
From August 1990. It was in the form of a note sent to all the people in the statistics group of Bell Labs, where I’d worked that summer. To all: Here’s the abstract of the work I’ve done this summer. It’s stored in the file, /fs5/gelman/abstract.bell, and copies of the Figures 1-3 are on Trevor’s [...]
The minimum variance portfolios have slightly reduced correlations to assets in weight-constrained portfolios. Previously “Portfolio diversity” introduced the topic of asset-portfolio correlations. It also generated four sets of long-only random portfolios as of the start of 2011 using constituents of the S&P 500: exactly 20 names, weights between 1% and 10% exactly 200 names, weights … Continue reading →
When I was at SAS Global Forum last week, a SAS user asked my advice regarding a SAS/IML program that he wrote. One step of the program was taking too long to run and he wondered if I could suggest a way to speed it up. The long-running step was [...]
by Yanchang Zhao, RDataMining.com My book in draft titled “R and Data Mining: Examples and Case Studies” is now available on CRAN at http://cran.r-project.org/other-docs.html. It is scheduled to be published by Elsevier in late 2012. Its latest version can be … Continue reading →
An interesting recent article emphasized that asking students to generate what should be reported from a Bayesian analysis also gets them to think about why things need to be reported, which in turn can get students to understand better how Bayesian an...
The Brain Chronicle blog is an attempt to share with the R and scientific community at large some methods, recipes and other thoughts that emerge from my day-to-day work as a computer biologist researcher.
I have posted previously about the open data available on Socrata (https://opendata.socrata.com/), and I was looking at the site again today when I stumbled upon a listing of levels of various radioactive isotopes by US city and state. The data is ava...
The recent Hack/Reduce hackathon in Montreal was a tonne of fun. Our team tackled a data set of consisting of Bixi (Montreal’s bicycle share system) station states at one minute temporal resolution. We used Hadoop and mapreduce to pull out some features of user behaviours. One of the things we extracted was the flux at
Yair pointed me to this awesome blog of how the NYT people make their graphs. This blows away all other stat graphics blogs (including this one). Lots of examples from mockup to first tries to final version. I recognize a lot of what they’re doing from my own experience. Also from my experience it’s hard [...]
