When performing a subjective Bayesian analysis, one aspect of the analysis is to build a prior based on subject matter knowledge from an expert. This process is called prior elicitation. It is common that experts (and others) will underestimate their own uncertainty. From the Pharyngula blog, I recently found a website measuring what they call `risk intelligence’ or RQ. The idea behind the website is to measuring how accurately you estimate your own uncertainty in your knowledge about facts in this world. This type of assessment might be valuable in adjusting the self-estimated prior uncertainty to a more realistic estimate of uncertainty. Since I will tell you how the test works below, I would suggest you try out the quiz for yourself by going here before I give away any secrets.

The test asks you to give your probability of 50 statements being true where you can choose from the probabilities 0%-100% in steps of 10%. It then lumps all the questions you gave X% to and calculates the percentage of statements in that group that were true. It compares X% to the percentage that are true. Do this for all percentages and then add up the absolute (?) differences and you have a measure of how accurately people estimate their own uncertainty. So I took the quiz and you can find the results by going here and using the drop down box to choose the test results from 2010-02-05. I scored a 60, which the test says is average. Some of the interesting results are that I choose 0% three times and 1 of the 3 times the statement was actually true. Of the times I chose 90% only half of the answers were true. In fact, of the times I choose 60,70,80, and 90% only half of all these answers were true. At least I got all the 100% answers correct.

Just to get an understanding of how the test works, I retook the quiz and answered 50% to all questions. The resulting RQ score was 52. I’m guessing you can get a zero only if you answer 0% and 100% for all answers and in exactly the incorrect way. I’d be curious if you can get an RQ of 100, if you answer all questions 0% or 100% correctly. I don’t know what the quiz would do with the percentages 10%-90% since you never actually answered those to any questions.

Here is a graph of the cost of a 30-second superbowl ad that I borrowed from the The Big Picture blog. The title of the post there is `The Superbowl As An Economic Indicator’. If it was a good indicator, why the big jump in 2009. Clearly everyone knew that the economy was declining last year, but yet the spending on a 30 second commercial was a larger than expected increase over the previous year.

I received this in my LinkedIn mailbox and yes, my name is spelled incorrectly:

Hi Jared. RTI is looking for a PhD level Research Biostatistician in RTP, NC, and the DC Metro area. Do you know anybody who may be interested? I’ll be glad to send you the job description or it can be found on RTI’s website, Job ID#12422.

Thanks.

Ellen Benzine
RTI International

If I were a recent college grad (and especially if job prospects were looking slim), I would think about entering the Google Health Corps.From the link:

GHC is a unique program that enhances a fellow’s cultural experience by pairing cross cultural teams – one fellow from the host country and one international fellow. Once accepted, all chosen fellows must complete a summer training course sponsored by Stanford University. This year GHC has 32 open positions with locations ranging from Burundi, Rwanda, New Jersey, Malawi, and Massachusetts. We believe that Global Health Corps offers a unique experience that enables young professionals to gain valuable experience for strengthening global public health equity.

While reading about the 10 best google labs experiments, I found out that Google has a map of Mars. There is also an option to see a google-earth view of Mars.

I have a history with Mark Yudof. Okay, it’s not really much of a history, but he was the president of the University of MN when I was a master’s student there. Now he is the president of the University of California system. He was interviewed recently by the NYTimes. I can’t imagine him coming off any worse. Basically my take home message from this interview is that we pay him $540,000/year, provide a pension and housing allowing for him to smile, shake hands, and tell jokes.

Here is a quote from the article:

How did you get into education?
I don’t know. It’s all an accident. I thought I’d go work for a law firm.

Seriously?? Is he trying to get fired? My guess is that he is because he has some sort of golden parachute and he doesn’t want to deal with the problems at the UC system.

I remember reading Andrew Gelman’s blog on 1 April 2008. The title of the post was “Why I don’t like Bayesian statistics”. Seeing as how Gelman’s work is pretty Bayesian, I was a bit confused until I realized it was April Fool’s Day. Gelman edited this blog post and published it in Bayesian Analysis, a journal specifically for all things Bayesian. You can find the article as well as 4 comments and a rejoinder here. There are no truly anti-Bayesians here, but the articles give a look into some of the questions of Bayesian analysis that are answered and some that are not.

I did learn a few things while reading these articles. One in particular stands out. The comment is in reference to most Bayesian analysis using conjugate priors out of convenience rather than truly representing prior information. These conjugate priors are typically used for computational reasons. Kadane points out that any prior can be well approximated by mixtures of conjugate priors. Using these mixtures allows accurately capturing prior information, but also retaining computational simplicity.

Finally, I’ll end this post with a quote that comments on the objective versus subject statistical analysis debate that appears in non-Bayesian as well as Bayesian statistical analyses.

Statistics is made of subjective procedures that yield objectively testable results.

Have you ever thought about the possibility of living on Mars? National Geographic recently put out a time-table for terraforming Mars that it might take about 1,000 years. Even then, humans on Mars would need to use scuba gear to go outside. The basic idea of the terraforming is to release carbon dioxide (CO2) into the martian atmosphere by crashing the planet with meteors to release CO2 or create factories to produce CO2. I wondered about the possibility of transporting CO2 from Earth to Mars, solving two problems at the same time. This doesn’t seem likely since transportation to Mars is a huge cost, but perhaps we will create technology that will make that transportation cheaper.

When H1N1 initially emerged, there were fears of a global catastrophe. In hindsight, it appears H1N1 is actually milder than most seasonal flu. In light of this hindsight, institutions (governments, hospitals, etc) are wondering how real the threat of catastrophe was and whether the WHO’s alarmist warnings were influenced by corporate interests, namely vaccine producers. Predictably, WHO officials say there is no link and an internal investigation is on-going. So I suppose we should expect to hear something in mid-2014 (sarcasm emoticon anyone?).

I see the story perhaps somewhat differently. Initially H1N1 (then called swine flu) was a big concern. The first reports coming out of Mexico were that mortality rate was high and those dying were young to middle-aged individuals. The mortality rate was inevitably high because the denominator was too small, i.e. many more people already had H1N1 we just didn’t realize it. Those affected was probably biased as well since an autopsy, or other reason for death measure, is less likely to be performed on older individuals than on seemingly healthy middle-aged individuals.

<speculation>I can see a situation where WHO was very concerned and called up vaccine manufacturers to ask how quickly a vaccine could be produced. In turn , maybe WHO gave the vaccine producers some kind of guarantee about purchasing vaccine. With this guarantee, vaccine producers ramped up production capabilities. As data rolled in that provided information about the lethality of H1N1, the question is whether the WHO should still have been pushing the vaccine or not.</speculation>

I will be curious to see whether there is any truth to this speculation.

On a separate note, my favorite quote from the above linked article is

Dr Fukuda rejected comparisons between seasonal flu and swine flu – describing them as like comparing oranges to apples.

Seasonal flu figures were based on statistical models, whereas every swine flu death had been confirmed in a laboratory, he said.

I wonder how he meant this statement. My guess is that he doesn’t trust the statistical model flu figures whereas he is confidence in the H1N1 flu laboratory confirmed deaths. My interpretation is that clearly the swine flu deaths have been under-counted, similar to how the census undercounts minority groups.

I guess my previous post indicating that Mars Spirit might be dead was a bit premature. In fact, Mars Spirit appears unable to move from its current location, but its instruments are still working and therefore it can still perform scientific inquiry for however far out its arms and cameras will reach. Still, it appears that NASA has given up on the possibility of Mars Spirit rover ever moving from its current location (shown below) due mainly to failure of 2 of the 6 wheels.