Wednesday, October 31, 2012

Willful statistical illiteracy

The fine folks over at Simply Statistics have a very good educational article about the difference between the probability of winning an election and vote share. This article stems from a controversial column over at Politico criticizing Nate Silver and his election forecasts.

Twitter responses are even worse. Conservative filmmaker John Ziegler calls Nate Silver a “hyper-partisan fraud” who is “not an expert on polls.”

image

Glenn Thrush mentions a “conservative 538:”

image

And it’s not hard to find other examples.

I’ve run into this reaction a bit, especially when it comes to politics. There are a large group of people, who will dismiss any evidence going against their beliefs. I guess the punditry wasn’t so dismissive of Silver in 2010.

At any rate, I give a recommendation I rarely give: read this Politico article and the comments (ignore the “conservatives aren’t bright” nonsense, which is the same stuff coming from the left).

And let’s thank Nate Silver, RealClearPolitics, and all the honest pollsters who try to shine some data on this election.

Monday, October 29, 2012

The most valuable thing about my little stat blog network project

So, I decided to construct the linking graph through blogrolls, and finally settled on using a manual process. The best part of this project is really finding out for myself all the great content out there!

Monday, October 22, 2012

SNA class proposal

I’ve been taking several classes through Coursera (nothing against the other platforms; I took two of the original three classes via Stanford and just stuck with the platform). The latest one is Social Network Analysis, which has a programming project. Here is what I have posted as a proposal:

Ok, I've been thinking about the programming project idea some, and at first I was thinking of analyzing the statistics blogging community, mostly because I belong to it and I wanted to see what comes out. The analysis below can be done for any sort of community. I've developed this idea a little further and wanted to record it here for two reasons. First, I simply need to write it down to get it out of my head and in such a way that the public can understand it. Second, I'd like feedback.

As it turns out, I took the NLP class in the spring and think there's some overlap that can be exploited. (This comes up nicely in the Mining the Social Web and Programming Collective Intelligence books.) There are measures of content similarity, such as cosine similarity, which are simple to compute and reasonably work well to see how similar content is. Content can then be clustered based on similarity. So, then, I have the following questions:

  • What are the communities, and do they relate to clusters of content similarity?
  • If so, who are the "brokers" between different communities, and what do they blog about? There are a couple of aggregators, such as StatBlogs and R-Bloggers, that I imagine would glue together several communities (that's their purpose and value), but I imagine there are a few others that are aggregator-like + commentary as well. Original content generators, like mine, will probably be on the edges.
  • Is it better to threshold edges based on a number of mentions, or use an edge weight based on the number of mentions?
  • If I have time, I may try to do some sort of topic or named entity extraction, and get an automated way of seeing what these different communities are talking about.

Saturday, October 20, 2012

Nate Silver on The Daily Show

Watch it!

There’s an interesting conversation about how the campaigns use analytics in get out the vote efforts. It doesn’t go a lot in depth, but I think this is an important aspect of campaigns that will come out into public view in the next couple of election cycles.

Of course, you can find his blog at http://fivethirtyeight.blogs.nytimes.com/.

Wednesday, September 19, 2012

Data cleaning is harder than statistical analysis

Statistical analysis is relatively hard, but it is a piece of cake compared to data collection, cleaning, and manipulation. In fact, in clinical trials research, we spend millions of dollars to develop and advance the capability to effectively manage data. Just about any clinical research organization worth the price has a strong data management department that they’ve spent a lot of time cultivating.

It’s time to take this a step further. In my workplace, we have a very close integration of the statistics group (consisting of statisticians and statistical programmers) and the data management group. In the latest issue of their newsletter, the Society for Clinical Data Management has included an article for the optimal collaboration between statisticians and data managers.  (I take this a step further and include the medical writer.) This collaboration takes a lot of time – time I could be spending doing statistical analysis. However, if the statistical analysis involves working around fewer data issues, it’s all worth it.

Monday, September 10, 2012

Exercise helps statisticians

Statistics is a rather sedentary job, and, over the years, I found my effectiveness decreasing as I found fewer “peak” hours in the day. I also gained a lot of weight. The number of migraines I experienced went from about two a year to about once a month.

In the last two or three years, I’ve been getting out of my chair to go for runs, I’ve taken up taekwondo, and also I a small gym that provides small-group personal training. In addition to adding who knows how many years to my life, they’ve really helped my focus and concentration when I’m doing statistics. I’ve also decided to take once a week or so off of thinking about statistics, which I’m finding helpful.

I only wish I had established these habits years ago.

Wednesday, August 29, 2012

Integrating R into a SAS shop

I work in an environment dominated by SAS, and I am looking to integrate R into our environment.

Why would I want to do such a thing? First, I do not want to get rid of SAS. That would not only take away most of our investment in SAS training and hiring good quality SAS programmers, but it would also remove the advantages of SAS from our environment. These advantages include the following:

  • Many years of collective experience in pharmaceutical data management, analysis, and reporting
  • Workflow that is second to none (with the exception of reproducible research, where R excels)
  • Reporting tools based on ODS that are second to none
  • SAS has much better validation tools than R, unless you get a commercial version of R (which makes IT folks happy)
  • SAS automatically does parallel processing for several common functions

So, if SAS is so great, why do I want R?

  • SAS’s pricing model makes it so that if I get a package that does everything I want, I pay thousands of dollars per year more than the basic package and end up with a system that does way more than I need. For example, if I want to do a CART analysis, I have to buy Enterprise Miner, which does way more than I would need.
  • R is more agile and flexible than SAS
  • R more easily integrates with Fortran and C++ than SAS (I’ve tried the SAS integration with DLLs, and it’s doable, but hard)
  • R is better at custom algorithms than SAS, unless you delve into the world of IML (which is sometimes a good solution).

I’m still looking at ways to do it, although the integration with IML/IML studio is promising.

Monday, August 27, 2012

Romney’s “secretive data mining”–could the same techniques be used for clinical trial enrollment?

Romney has been “exposed” as using “secretive data mining techniques” to find donors to his campaign in traditional Democratic strongholds. (These techniques can be learned in any of these free online courses offered through Coursera and Udacity along with the massive databases collected by the different parties.)

Of course, my thought is, can we use these techniques to find potential participants in clinical trials? I think that if we can work out the privacy issues, this represents a useful tool for clinicians to find not just trial participants, but patients who need to be treated, but for some reason are not being treated. This could be a win for everybody.

Other ideas:

  • using Google trends, much like Google uses to identify flu outbreaks
  • mining discussion boards
  • identifying need through blog networks

I’ll be taking the Web Intelligence and Big Data class through Coursera, so maybe I’ll get more ideas.

Monday, August 20, 2012

Clinical trials: enrollment targets vs. valid hypothesis testing

The questions raised in this Scientific American article ought to concern all of us, and I want to take some of these questions further. But let me first explain the problem.

Clinical trials and observational studies of drugs, biologics, and medical devices are a huge logistical challenge, not the least of which is finding physicians and patients to participate. The thesis of the article is that the classical methods of finding participants – mostly compensation – lead to perverse incentives to lie about one’s medical condition.

I think there is a more subtle issue, and it struck me when one of our clinical people expressed a desire not to put enrollment caps on large hospitals for the sake of a fast enrollment. In our race to finish the trial and collect data, we are biasing our studies toward larger centers where there may be better care. This effect is exactly the opposite of that posited in the article, where treatment effect is biased downward. Here, treatment effect is biased upward, with doctors more familiar with best delivery practices (many of the drugs I study are IV or hospital-based), best treatment practices, and more efficient care.

We statisticians can start to characterize the problem by looking at treatment effect by different sites, or using hierarchical models to separate out center effect from drug. But this isn’t always a great solution, because low-enrolling sites, by definition, have a lot fewer people, and pooling is problematic because low-enrolling centers tend to have way more variation in level and quality of care than high-enrolling centers.

We can get creative on the statistical analysis end of studies, but I think the best solution is going to involve stepping back at the clinical trial logistics planning stage and recasting the recruitment problem in terms of a generalizability/speed tradeoff.

Wednesday, August 15, 2012

Statisticians need marketing

I can't think of too much I would disagree with in Simply Statistics's posting on Statistics/statisticians need better marketing. I'll elaborate on a couple of points:

We should be more “big tent” about statistics. ASA President Robert Rodriguez nailed this in his speech at JSM. Whenever someone does something with data, we should claim them as a statistician. Sometimes this will lead to claiming people we don’t necessarily agree with. But the big tent approach is what is allowing CS and other disciplines to overtake us in the data era.
Apparently, the idea of data mining was rejected by most statisticians about 30 years ago, and it has found a home in computer science. Now data science is growing out computer science, and analytics seems to be growing out of some hybrid of computer science and business. The embracing of the terms "data science" and "analytics" puzzled me for a long time, because these fields seemed to be just statistics, data curation, and understanding of the application. (I recognize now that there is some more to it, especially the strong computer science component especially in big data applications.) I now see the tension between statisticians and practitioners of these related fields, and the puzzlement remains. Statisticians have a lot to contribute to these blooming fields, and we damn well better get to it.

We should try to forge relationships with start-up companies and encourage our students to pursue industry/start-up opportunities if they have interest. The less we are insular within the academic community, the more high-profile we will be. 
Stanford has this down to a business plan. So do some other universities. This trail is being blazed, and we can just hop on it.

It would be awesome if we started a statistical literacy outreach program in communities around the U.S. We could offer free courses in community centers to teach people how to understand polling data/the census/weather reports/anything touching data.
Statistics without borders is a great place to do this. Perhaps SWB needs better marketing as well?