Listening to the Twins tonight and hearing my fellow high-school alumnus Joe Mauer strike out it occurred to me that he’s been doing this a lot lately. It turns out that Joe is whiffing at double his normal rate. However, this has had no effect on his performance other that saving him the trouble of legging out ground-ball outs. (I think that is Joe’s plan all along, that is, preserving energy.) Anyways, by racking up so many “K”s Mauer accomplished a 15-game hitting streak during which he struck out at least once in each game. According to Elias Sports Bureau, that breaks the previous record of 11 games for this oddly hot/cold hitting–at least since 1910, when the major leagues began keeping track of strikeouts.
That reminds me of a fellow I golfed with on Monday at a charity outing where we played best ball. He led off our four-some on the first tee with a mighty swing that raised a lot of dust but not the ball. Re-gathering his wits he swung even harder, but to no avail–the golf ball remained teed up. But the third time proved the charm–an awesome drive straight and far down the fairway that ended up being our best ball–none of the others of us could top it. So that works…albeit it is very nerve wracking for spectators, I must say.
May’s National Geographic pictured a very impressive One Hundred Trillion Dollar bill from the Reserve Bank of Zimbabwe, which in November of 2008 hit the 79.6 billion percent level for inflation before stabilizing their currency. Check out the 100T note here. You can buy one of your own for less than ten bucks USD!
Meanwhile back home in here in the USA everyone is up in arms over a measly 0.1 percent difference in inflation caused by “chaining” our CPI. The gist of this is explained in this recent Time-magazine personal-finance column. It seems like much ado about very little. However, those who get cost-of-living adjustments (COLA) fight like crazy over anything that reduces their income. Here’s a spin on statistics: A 0.1 percent reduction from 1.5 percent is actually a 7 percent loss in COLA. No wonder seniors want to throw off those chains!
The fiddling with money supply and shenanigans on inflation computations reached a new low not long ago in Argentina when the government forced out statistician Graciela Bevacqua for rounding rather than dropping decimal points, which made the government look better with their official rate. It’s all reported here by The Economist. Now working in private industry Bevacqua continued to present a truer calculation on inflation and got fined $100,000 for her honesty. After an uproar from far and wide, including the American Statistical Association (ASA), the courts in Argentina overruled the government and spared this outspoken statistician, according to this news from Buenos Aires Herald. Someone ought to give her a medal for speaking the truth. But as the great statistician George E. P. Box said:
“Whenever we see virtue rewarded, we are completely surprised.”
“The fox knows many things, but the hedgehog knows one big thing.”
In the June 3rd issue of Chemical & Engineering News Frederick M. Peterson, a chemical engineer who went on to achieve a doctorate in economics, dissects what happens when “Scientists Tackle Finance.” He warns against the tendency of experts in one field being overly bullish about their ability to manage things outside of their specialty. These are the hedgehogs—people who make bold predictions and happen to be right long enough that they attract a strong following.
On the other hand, the foxes, who observe many things and adapt readily to differing situations, lack confidence about the chances of any particular path leading to success. They are seen as being weak and wish-washy, which is not very popular. Nevertheless, it may not be surprising that foxes do better than hedgehogs at forecasting, according to Peterson, who cites a seminal study by the School of Business at University of California, Berkeley.
The moral of this story is to be wary of anyone who expresses too much certainty about the shape of things to come. It does not pay to follow hedgehogs—they will ultimately go beyond their narrow limits of competence and roll into something very prickly.
This blog on Central limit theorem animation by Nathan Yau brought back fond memories of a quincunx (better known as a bean machine) that I built to show operators how results can vary simply by chance. It was comprised of push-pins laid out in the form of Pascal’s triangle on to a board overlaid with clear acrylic. I’d pour in several hundred copper-coated BB’s through a funnel and they would fall into the bins at the bottom in the form of a nearly normal curve.
Follow the link above to a virtual quincunx that you can experiment on by changing the number of bins. To see how varying ball diameters affect the results, check out this surprising video posted by David Bulger, Senior Lecturer, Department of Statistics, Macquarie University, Sydney, Australia.
I’ve diligently recorded my weight every several days for some years now. The short-term variation always astounds me—going up and down by a number of pounds from one week to the next. However, on average month-by-month my weight remains surprisingly stable. Unfortunately the trend over years is very slightly, but significantly, upwards. Thus my battle against the bulge continues.
A few weeks ago I stepped up for a weighing and received a pleasant surprise: It seemed that I’d dropped 10 pounds during a five-day business trip. Although deep down I knew this could not be, I indulged myself for the day with the thought that something magical had whisked away this weight. Then after getting home from work I got back down to earth by discovering that the base of the scale had got off kilter. I mentioned this to my wife and daughter. It was funny seeing them being so crestfallen—they also were hanging on to the belief in a mysterious, but real reduction.
I suppose all this supports the use of control charting* for filtering out common-cause variability (not worth reacting to) from statistically-significant process upsets (special causes that merit attention). At least that’s what my logical side says. On the other hand, it was fun to believe for some hours in supernatural forces. Ignorance can be bliss!
*(See this detailing posted by the George Mason University College of Health and Human Services.)
- Shocks to the Brain Improve Mathematical Abilities. (You ‘mathaletes’ should do some calculating before wiring up because the sample size for these findings is miniscule!)
- Brain, Interrupted-How distractions make us dumber. (The news here is mixed:Multitasking may be a myth but perhaps some people, with practice, can handle it.)
I hope this blog did not derail your train of thought. If so, go lick a battery to reverse the brain drain.
Last week The Scientist reported that “Bad Stats Plague Neuroscience”. According to researchers who dissected 730 studies published in 2011, neuroscientists pressed ahead with findings on the basis of only 8 percent median statistical power. This falls woefully short of the 80 percent power that statistician advise for experimental work. It seems that the pressure to publish overwhelms the need to run enough tests for detecting important effects.
“In many cases, we’re more incentivized to be productive than to be right.”
- Marcus Munafo, University of Bristol, UK
I’ve been watching with interest the trend for ‘flipping’ classrooms; that is, using time together for working on homework and leaving the teaching to web-based and other materials (books, still!) for students to teach themselves on their own time. At the college level this new educational approach for is gaining momentum via massive open online courses, called MOOCS.
For example University of Minnesota chemistry professor Chris Cramer will teach this 9-week MOOC on Statistical Molecular Thermodynamics starting next month. Follow the link and watch him demonstrate a thermite reaction. If anyone can make statistical molecular thermodynamics interesting, it will be him, I think, so I enrolled. It’s free, thus there’s nothing to lose. Also, I still feel guilty about getting an A grade in the stat thermo class I took 30 years ago—the reason being it was graded on a curve and thus my abysmal final score of 15 out of 100 got rated highly as the second highest in my class. As you can infer, it was not taught very well!
P.S. I recently unveiled a distance-based lecture series on design of experiments called the DOE Launch Pad. It augments my book (co-authored by Pat Whitcomb) on DOE Simplified. Contact me at mark @ statease .com to sign up. It’s free for now while in pilot stage.
See the results graphed on an experiment I just completed to decide whether to commute straight in to Minneapolis on Minnesota Highway 36 or take US Interstate 694 –a speedier, but longer, freeway bypass. Notice that the least significant difference bars do not overlap, thus providing more than 95 percent confidence that the scales tilt to one way (36) being faster–to put it simply.
For each run into work I randomly chose one route or the other based on a recipe sheet produced by Design-Expert software and timed it with a stopwatch app on my smart phone. Then I entered the results in the software and it gave me the answer I wanted.
It appears that I can save the better part of a minute by not shooting around on 694. That is good to know!
George Box passed away this week at 94. Having a rare combination of numerical and communication skills along with an abundance of common sense, this fellow made incredible contributions to the cause of industrial experimenters. For more about George, see this wonderful tribute by John Hunter.
My memorable stories about Box both relate to his way with words that cut directly to a point:
- In 1989 at the Annual Quality Congress in Toronto seeing him open his debate with competing guru Genichi Taguchi by throwing two words on an overhead projector–”Obscurity” and “Profundity”, and then after a dramatic pause, adding the not-equal sign between them. This caused Taguchi’s son Shin to leap up from the front row and defend his father. This cause the largest crowd I have ever seen at a technical conference to produce a collective gasp that one only rarely experiences.
- In 1996 at a DOE workshop in Madison, Wisconsin enjoying his comeback to a very irritating disciple of Taguchi who kept interrupting the lecture: “If you are going to do something, you may as well do it right.”
Lest this give the impression that Box was mean-spirited see this well-reasoned white paper that provides a fair balance of praise and criticism of Taguchi, who created a huge push forward for the cause of planned experimentation for quality improvement.
The body of work by George Box in his field is monumental. It provides the foundation for all that we do at Stat-Ease. Thank you George, may you rest in peace!