Comments, observations and thoughts from two bloggers on applied statistics, higher education and epidemiology. Joseph is an associate professor. Mark is a professional statistician and former math teacher.
Saturday, July 3, 2010
Narrow versus broad searches
What struck me as most interesting is that a complete strategy for improving a field likely embraces both approaches. The bloggers (foxes) are racing around asking naive questions in the search for an undiscovered solution. The academic researchers (hedgehogs) are refining the known solutions to make them actually optimal. Both approaches are actually very useful, on their own terms.
The thing to keep in mind is that the fox approach is going to generate a lot of failure. When I do epidemiology methods research, I always keep in mind that just beating he standard practice in the field is very hard to do. Heck, for a lot of problems, just getting substantial improvement in estimation over a carefully thought out linear regression model (regardless of whether the outcome is continuous or not) is surprisingly challenging. It can certainly be done and for some classes of problems, like time to event, the improvement is dramatic. Even more difficult, the current tools have been carefully refined and well understood -- developing a superior alternative is hard (just look at the number of methods papers published every month in statistics in medicine).
But every once in a while, a new idea shows up that leads to dramatic improvements, one way or the other, over conventional approaches. I think bloggers do a lot of the grunt work of looking around and trying to see if there is a superior paradigm or approach to looking at the current problems. Then academics take the slow and difficult process of incremental improvement.
It's a nice way of looking at the relation between these two approaches.
Risk Taking and success
The reason is that success is not a single dimension, nor is happiness. If you have the incredible natural talent and drive to be the very best you can possibly make a risk taking strategy work because you have the ability to recover from failure. In the same sense, the very rich can try high risk investment strategies as they may still be well off even if the strategy fails. My favorite example of this is somebody like Garth Brooks trying to be Chris Gaines; Garth was a sufficiently well known star that he could recover when the "Chris Gaines gamble" did not work out.
But to reach these levels of focus, is it not likely that other things in life may have to be sacrificed? It is true that highly successful people are driven and focused but do need to remember that this focus often comes at a surprising cost. Alexander the Great was a successful general but would anybody envy his personal life?
All of which is to say that strategies for success are complicated, at best, and that people aren't simple at all. Which, come to think of it, is probably a good starting point for all of these discussions.
Role models
Inspiration. Success. Confidence. Passion.I learned that the author would share "the life lessons and hard-won insights that made her a rising star in the business world" and that whether the reader was "landing that first job, navigating the workplace,or making a lasting impact," the author would show how to "Step up and get noticed at work -- focus and efficiency will open doors."
No one is born with these qualities, but they are the key ingredients for reaching goals, building careers or turning a blueprint into a breathtaking skyscraper.
The author's name was Ivanka Trump.
The book is the Trump Card.
It's available in paperback.
Friday, July 2, 2010
How blogging is like SCTV
It is rare in any medium to be free make things the length they ought to be, but a blog is one of the few exceptions. In a blog you you spend hundreds of thousands of words on a subject or you can cover it in the span of a haiku. We don't always make the best use of that freedom but we should at least appreciate having it.
An actress prepares for the wrong role -- 3:06
Dick Cavett finds the perfect guest -- 2:44
A schlocky horror show accidentally books an art film -- 8:11
Paper review times
Another point to remember is that you can't submit to multiple journals at once, so the reviewing time is an opportunity cost for the researcher. This is of particular relevance for students like myself, who need to get papers published quickly in order to be able to show them on a CV and thus get a job (and the opportunity to do more research.
Later on, when one has a track record, it makes sense to aim high on a paper that has potential. It's never possible to be sure about a specific paper as one of the factors that goes into the decision of a journal to accept or reject a paper is what other papers have arrived recently. Back when I started out in Epidemiology (seems like a lifetime ago), this was true of our journals (like the American Journal of Epidemiology) as well. Fortunately, AJE has made a massive effort to improve things. This paper by Raymond J. Carroll shows a review time for AJE in 1999 of 15 months (figure 3). Yikes!
On the other hand, it is unclear what the optimal point is. I know of researchers who submit all of their papers to the top five medical journals "just in case" because it only takes a couple of months and, who knows, lightning might strike.
But it remains a very tough problem for junior people, like myself, who need to maintain momentum (both the volume of papers and the speed of papers). I do like the BMC Medicine model where the general journal reviews the paper and then refers the paper to a sub-journal if they think it would work there instead. I would publish in BMC journals a lot more if I was not so broke as I like their actual policies and practices a lot!
Charms and Mogul Dust
There is really no way to draw a useful analogy between the careers of Dylan and Jordan and what the rest of us face, but of course, that's not the point. The gurus use these men in their examples for the same reason that our ancestors would dress up like bears and growl and snarl at each other around the campfire. It's a primitive but still appealing magic of association and imitation.
Eating a box of Wheaties with Derek Jeter on the front will not raise your batting average, wearing a LeBron James jersey will not help your jump shot and trying a career move just because it worked for Dylan or Jordan will probably turn out to be a bad idea.
Thursday, July 1, 2010
One less reason to read the New York Times
We've lost Judson's subtle and entertaining insights into evolution. We're left with John Tierney asking if your dog is really sincere.
Publishing Equilibria
On the other hand, the current system of scientific journals is, in many ways, a complete joke. The demand for referee reports of submitted articles is out of control, and I don't see Arxiv as a solution, as it has its own cultural biases.
I wonder if the problem here is not one of equilibria. Journal articles have become the an important way to measure productivity and to define success. As a result, researchers who are good at producing journal articles prosper. To change the system you have to overcome the intertia of the decision makers often being those reseachers who were successful at the current system.
Most systems of prestige tend to be hard to overturn and it's unclear as to what would be a good pathway to doing so. I tend to wonder about marginal improvements as these are more likely to be adopted. But it is pointless to fight for scientific expression to be done on blog posts if employers count grants and papers to determine future employment.
So what are the improvements at the margin that are possible?
Wednesday, June 30, 2010
The problem with innovation is that it sometimes solves problems
I'm in my mid-Forties so, other than some brief experiments with facial hair, I've been shaving more or less daily for around thirty years. I started with my dad's old twist-to-open razor that took a two sided blade. They were known as safety razors which always seemed an ironic name for a product that routinely caused bleeding with regular use.
Twin blades had been around for years but they were still gaining acceptance. There was a wide-spread sense that they were nothing more than gimmicks. Saturday Night Live even had a parody commercial touting a three-bladed razor that looked remarkably like what would be the Mach Three.
But as silly as they sounded, the twin blades greatly reduced the blood loss. It was one of those innovations where the results actually matched the hype.
A few years later the triple blade razor was introduced (prompting another, almost identical SNL parody). The new technology produced a closer, more comfortable shave and, best of all, virtually eliminated the bleeding.
Of course, there are confounding factors (I'm older and I've had a lot of practice shaving) but there are still occasions when I'm on the road and have to go back to an older style razor and the result is always bloodshed.
The triple-bladed razors are a great product. As a long-time, steady customer I can give them an unqualified endorsement.
That's a terrible problem for the people who make razors. They have a new generation which, they claim, will give a closer shave with less tugging and irritation. I believe them. These are smart people with a history of successful technological innovation and as far as I can tell, all of their products have lived up to the claims made about them.
Unfortunately for them I am not a motivated customer. If there was, at this very moment, blood dripping from my face, I would certainly be an easy sale. If the last time I had used rubbing alcohol as an aftershave I had grasped my face and moaned "Oh God, make it stop!", you certainly would have found me receptive to an upgrade.
But Gillette and Schick have solved those problems for me, and when you truly solve a problem for a customer, you create one for the marketing department.
How to REALLY lie with statistics
The catch comes from Media Matters via Mark Thoma.
Here is the same graph with vertical lines for full comic effect.
Go ahead, measure them for yourself. It's fun.
In all fairness to Fox, the period from September '08 to March '09 did feel like a long time.
Bob Dylan, the Monkees and the flooded landscape analogy
Let me first describe a distinction between the Monkees and Bob Dylan. Bob Dylan gets laughed or booed off the stage every ten years, whether he wants to or not. He got booed off the stage when he went electric and again when he went gospel, and most recently with his horrendous Christmas album. The Monkees never get booed off stage, because the Monkees play "Last Train to Clarksville" exactly the same way they did it 30 or 40 years ago. Here's the thing: Bob Dylan keeps selling out stadiums and no one goes to see the Monkees, because the Monkees aren't doing anything worth noticing. There are people who have succeeded who just keep playing the same song over and over again, whatever that is that they do.Think of a musician's career as a landscape where creative decisions like repertory, genre, style, arrangements give the location and concert sales are the fitness function. (see here and here for previous posts on landscapes)
In Godin's example, the Monkees have stuck very close to a local maxima that has sank over the years (the sticking close part doesn't actually match reality all that well -- Mike Nesmith had a run of innovative and interesting projects in the early days of music video -- but for the sake of the post let's overlook that part). Any small to moderate change in repertory or arrangement or style would move them to a lower point on the landscape.
I think I may be stealing this from Stuart Kuafmann, but let's flesh out the metaphor a bit and add water. Our landscape dwellers can travel freely on dry land but they can only swim very short distances. Exactly how does this relate to our real life example? Remember that altitude in our landscape corresponds to ticket sales. In order to stay viable, ticket sales for a touring act have to stay above a certain level. If the sales fall below that level, the act loses bookings and can no longer cover its expenses. Of course, like any other business, the act can run at a loss for a while (swim) but that's obviously not a long term solution.
Godin suggest that a willingness to, in our analogy, move to another optima is the key to success. Dylan made the move and thrived. The Monkees stayed put and whithered. But how comparable were the two situations?
Dylan had a steady source of income from other artists covering his songs. In landscape terms, he was a good swimmer (of course, so was Nesmith who got a tiny check every time you used that little Liquid Paper brush). More importantly, Dylan didn't have that far to swim. He might not even have needed to get wet. At least a portion of Dylan's fan base were going to stay with him no matter where he went on the musical landscape and given his reputation (and phenomenal talent, though I'm trying to leave that out of the discussion), there was a maxima waiting for him at pretty much every genre and subgenre of popular music. Those moves might not have been as artistically or commercially successful as the ones he made but Dylan was going to remain viable no matter where he went.
What about about the Monkees? Musically they weren't a bad line-up. Dolenz was a veteran child actor, Jones was a Tony nominee for Oliver! and Tork and Nesmith were both accomplished musicians. Highly successful careers have certainly been built on less, but what did their career landscape look like? Compared to Dylan's collection of tightly-packed peaks, the Monkees had a lonely island surrounded by what looked like a large and empty ocean. The vast majority of their fan base was location specific. When they moved away from that location they hit deep water very quickly.
It is, of course, possible that the group could have focused on coming up with new songs and a new sound with the hope of finding a new audience. This is a dynamic landscape, and where the artist chooses to go is one of the factors that affects it. There might not be a concert market for the Monkees playing new grass or thrash metal now but that doesn't mean there won't be one in the future. Sometimes, by playing music no one wants to hear, you can create a demand for that music. To return to the landscape analogy, treading water in one spot can cause an island to rise up beneath you. It has been known to happen but it's probably not something you want to count on.
In the case of the Monkees, the water-treading strategy would be particularly risky since their reputation is likely to work against them if they try something radically new. This is probably why Nesmith chose to use his own much less well known name for the Grammy-winning Elephant Parts rather than trying to sell it as a Monkees project.
Which brings us back to Mr. Godin and the advice books he and other business gurus dump on the market every year. These books gush out at such a rate that there are actually companies that put out fifteen page versions so that executives can at least give the impression that they have read the latest releases. The Dylan/Monkees example is sadly representative. It takes one of business gurus' favorite truisms (take risks, i.e. move out of your comfort zone, i.e. they laughed at Henry Ford), bills it as a fundamental key to fabulous success (fabulous as in fabled as in obviously untrue) then backs it up with an irrelevant but impressive sounding example.
Godin is telling businesses to be like Bob Dylan and to make radical moves that may piss off your customers and invite scorn and mockery. The trouble is very few businesses are Dylan-at-Newport. The majority are the Monkees-at-the-state-fair. They have something they do reasonably well. If they stick close to their local maxima they can turn a decent profit and have a pretty good run. If they follow Mr. Godin's advice they will sink like a cinder block and never be heard from again.
Monday, June 28, 2010
Grants!
I know that I need to keep at it but it is one of the hardest things for me in my current role!
It is possible to have a simple question in a complex field
It is precisely from this low-level vantage point that I am totally puzzled by the willingness of many who fearlessly and breathlessly opine about economics, especially macro- economic policy. Deficits, short-term interest rate targets, sovereign debt are all chewed over with a level of self-assuredness that only someone who doesn’t know more could. The list of those exhibiting this zest also includes, in addition to those mentioned above, some who might know better. They are the patron saints of the “Macroeconomic Policy is Easy: Only Idiots Don’t Think So” movement: Paul Krugman and Brad Delong. Either of these men will assure their readers that it’s all really very simple (and may even be found in Keynes’ writings).There's an obvious but important point that Dr. Athreya either manages to miss or avoid, namely the distinction between a simple field and a simple question. In almost all fields, even the most complex and challenging, there are simple, easily-answered questions.
Krugman and Delong frequently argue that some colleagues, policy-makers, journalists or politicians have reached the wrong conclusion about a simple point in macroeconomics. They sometimes also contend that some of these errors are partially the result of idealogical thinking or outside influence (both of which have occasionally been observed in economics).
Dr. Athreya is free to dispute Krugman and Delong's arguments either by showing that the question is not simple or that it is simple but they still got it wrong. If he could actually prove either he could really advance the debate. Instead he seems to argue that the existence of simple questions implies a simple discipline.
And for someone of Dr. Athreya's qualifications and accomplishments, that's kind of simple-minded.