Archive for category Uncategorized
Pi day—tau be or not tau be, that is the question
Posted by mark in pop, Uncategorized on March 14, 2020
Math-savvy pizza and pie shops around the world will be celebrating this afternoon of 3/14 at 3:14 pm to honor the mathematical constant pi.
Rounding pi to 3.14 suffices for most rational people, but those of you who are trained matheletes might like to carry this never-ending irrational number out to 100 or a 1000 decimal places. If so, knock yourself out at this post by math.com. You might as well quit at this point because the record is now 50 trillion digits, held by cybersecurity analyst Timothy Mullican who used 303 days of computation to complete this calculation, which he detailed here.
A good way to build up your chops on pi is to memorize a ‘piem’, that is a poem in which the length of each word represents a number, for example, “Now I need a drink, alcoholic of course, after the heavy lectures involving quantum mechanics.” See a much longer (101 digits!) piem sung by musician Andrew Huang and many other amazing feats related to pi in this article by Andrew Whalen posted today by Newsweek.
Sadly, some mathematicians are reigning in the pi parade by insisting it be doubled to the constant tau.
“To describe 3/4 of a circle in trigonometry, you would say 3/4 tau radians. But in the pi world, that’s 3/2 pi radians. ‘Blegh!’ says Prof. [Bob] Palais [Utah Valley University]. ‘People are so ingrained that they don’t even see how stupid it is.’”
For Math Fans, Nothing Can Spoil Pi Day—Except Maybe Tau Day
Wall Street Journal, 3/14/20
You’d best circle (ha ha-math joke) June 28 to celebrate Tau Day, even though that’s no reason to eat pizza or any other kind of pie.
Permanent calendar proposed to eliminate leap day
Posted by mark in pop, Uncategorized on February 29, 2020
“Those born on Feb. 29 know they exist, but the computer at the DMV is skeptical.”
Subheadline for the Wall Street Journal article today about how Leap-Year Babies Fight a Lonely, Quadrennial Fight for Recognition
Today being a day that comes only every four years is special—even more so now that my niece delivered a leap-year baby girl. Unfortunately, this precious little leapling (“LL”) faces a lifetime of calendar kerfuffles with computer systems that do not compute February 29th birthdays. However, a solution is at hand: the Hanke-Henry Permanent Calendar (HHPC). By HHPC’s reckoning this special day is March 2nd and comes again on Saturday next year and every year thereafter—no need for LL’s parents to wait four years to celebrate her first birthday.
Being that my birthday would always fall on a Monday, I cannot build much enthusiasm for the HHPC feature of any given date always falling on the same day (LL lucked out, though). Other off-putting days are Independence Day being on a Wednesday and Halloween being eliminated due to October ending at 30 days. But the weirdest aspect of HHPC is the “Xtr” week every 6 years. This year of 2020 features an Xtr, for example. Minnesotans do not need 7 more days of winter!
PS. Watch the video to see what would happen, if we did not add a day every 4 years: Eventually summer would become winter!
Major League Baseball experimenting with robot umpires
Posted by mark in sports, Uncategorized on February 19, 2020
After a somewhat successful* year-long trial of automated balls and strikes (ABS) in the Atlantic League, MLB will bring in these ‘robots’ to second-guess their human umpires at nine of Florida’s spring-training games. The ABS system makes use of TrackMan radar technology, already in play for StatCast.
After MLB’s tech-team improves ABS’s reliability and accuracy, it might be worth using, but only if it speeds up the game. Using ABS simply to challenge calls will just make things worse, while eliminating the spectacle of on-field blow-ups by volatile managers like Billy Martin (former Minnesota Twin). When the calls are made by invisible radar, who do you throw the dirt at?
“You turn back (to the umpire and say), ‘TrackMan?’ They say, ‘Yeah,'” “‘Well, I’m not going to argue with you.’ Because it’s the robots.”
Southern Maryland Blue Crabs outfielder Tony Thomas commenting on the experimental use of ABS in the Atlantic League
PS. When the baseball robots get smart enough to call balks, then we’d all best bunker down for them taking over the world.
*Baseball America reporting Imperfections And All, Robo Umps Make Significant Impact
Experiment provides fetching evidence about wolf puppies
Posted by mark in Nature, pop, Uncategorized on January 21, 2020
Swedish zoologists reported this month in iScience that Intrinsic Ball Retrieving in Wolf Puppies Suggests Standing Ancestral Variation for Human-Directed Play Behavior. This counteracted widely-held beliefs that wolves do not socialize with humans. It may suggest that ancestors of dogs were primed for domestication.
Given the small sample size—only 13 wolves—I am not so sure. But I always feel better after encountering puppies like Flea pictured in Gizmodo’s engaging report on the Swedish study. I look forward to more rigorous research on wolf puppies and hope to be picked as a tennis-ball tosser.
“When I saw the first wolf puppy retrieving the ball, I literally got goosebumps.”
Christina Hansen Wheat, a co-author of the study and a researcher from Stockholm University.
Taking a shot at ruggedness testing with water pistols
Posted by mark in pop, Uncategorized on September 26, 2019
Being on the committee for ASTM International (formerly known as American Society for Testing and Materials) Standard Practice for Conducting Ruggedness Tests, I am a big fan of applying multifactor design of experiments (DOE) to systems before they go out to the field. For example, most homes in Florida feature stucco exteriors, which in some cases cannot withstand storm-driven rain from pushing moisture into the walls. Black mold can then build up to toxic levels before being discovered by home owners.
A less alarming, but still troublesome, combination of wind and rain is being combated by the trustees of Charles Rennie Mackintosh’s masterpiece Hill House in Glasgow, Scotland. The house, battered by rain every other day for 115 year, now soaks up water “like a sponge”. To keep it from dissolving “like a sugar cube”, National Trust Scotland (NTS) built a chainmail box around the home in June. They’ve scheduled a Douse the House this Saturday for visitors to test the ruggedness of the new exterior by shooting it with water pistols—”the bigger the better”! The experiment takes place at 2.30 pm and entry is free.
NTS’s Douse the House organizers had best beware of Mark Rober and his Guinness World Record sized Super Soaker. That might turn out to be a destructive testing device, even with chainmail as the barrier.
Designed experiment creates egg-splosive results
Posted by mark in design of experiments, Uncategorized on August 20, 2019
Design-Expert® software version 12 (DX12) released this summer with a cool new tool to model binary responses, for example, pass-versus-fail quality-testing. For what it’s worth, the methodology is called “logistic regression”, but suffice it to say that it handles results restricted to only two values, typically 0 or 1. The user deems which level is a success, most often “1”.
During development of DX12 Stat-Ease moved to a penthouse office on a building with a cascade of balconies. So, when our programmers, led by Hank Anderson, considered how to test this feature with an experiment, they came up with the idea of trying various packing on eggs to see if they could be dropped some distance without breaking—a project that high-school science teachers assign their students. However, we figured that our neighboring tenants down below and our new landlord might not be very happy about the mess that this would create. Therefore, Hank and his team took a less problematic tack by testing various factors for microwaving eggs to an edible stage. This experiment (or ‘eggs-periment’ if you like) also was more productive for varying the diet of the programmers from their staple of boiled ramen noodles—the focus of a prior DOE.* If they could achieve consistent success in cooking eggs by microwave, a combination of these with ramen might be the ideal sustenance for awesome coding for new versions of Design-Expert.
The Stat-Ease experiment began with a bang during the range-finding stage with an explosive result. You might say that the yolk was on us—bits of overcooked egg and shell dispersed throughout the chamber of the microwave. The picture below shows the messy aftermath (note the safety glasses).
After this learning experience (‘eggs-perience’?), Hank and his lab technician, Mike Brownson, settled into a safer range of factors, shown below, that kept the contents from reaching the catastrophic breaking point:
- Preheat—0 to 180 seconds
- Cooking time—120 to 420 seconds
- Power—60 to 100 percent
- Salt—0 to 2 teaspoons
- Egg Size —Large or Jumbo
Hank and Mike, with input from Stat-Ease Consultant Martin Bezener, put together an ambitious design with 92 runs using Design-Expert’s custom design builder (i-optimal) for response surface methods. Heads-up: When responses are restricted to just two outcomes (binary), many more runs are required to provide adequate power than would be required for a continuous measure.
The investment of nearly 100 trials for the ‘eggs-periment’ paid off by producing significant results on pass/fail measures of undercooking and overcooking. For example, the 3D graph below shows the probability of eggs being undercooked as a function of time and power for the microwaving. Notice by the corner at the left being cut off that potentially catastrophic combinations of high power and long cooking were excluded via a multifactor constraint. Clever!
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Based on models produced from this experiment, Design-Expert’s multiple-response optimization recommends a most desirable setup for microwaving eggs as follows: Heavily salted jumbos preheated to the maximum level and then cooked for 315 seconds at medium power.
Thanks to the research by Hank, Mike and Martin, our programming staff now is fueled not just by ramen, but also with eggs—a spectacular success for DX12’s new logistic-regression tools!
* “The Optimal Recession-Proof Recipe”, Brooks Henderson, pp 1-2, September 2012 Stat-Teaser, followed up by “Confirming the Optimal Ramen”, p3, January 2013 Stat-Teaser.
Over half of all children have below-average reading skills
Posted by mark in Education, leadership, pop, Uncategorized on June 24, 2019
Yes, you read that right—this statistic was cited by Eugenia Cheng last weekend in her column for the Wall Street Journal on why Averages Aren’t Always What They Seem. In this case, a small number of excellent readers skews the distribution to the right.
But none of this applies to my offspring, them being in the Lake Wobegon region where all the children are above average.
I would never admit it, but deep down I realize that I’ve succumbed to the superiority illusion, aka the Dunning-Kruger effect. As advised in this June 3rd post by Forbes you’d best be careful not to be taken in by individuals who consistently overestimate their competence due to this cognitive bias.
Steve Carell took the superiority illusion to an absurd extreme as the manager Michael Scott in the “The Office” television series. It’s funny unless you are subject to someone like this.
“The knowledge and intelligence that are required to be good at a task are often the same qualities needed to recognize that one is not good at that task—and if one lacks such knowledge and intelligence, one remains ignorant that one is not good at that task.”
— David Dunning, professor of psychology at the University of Michigan
“Stupid people are so stupid they’re unable to grasp the fact that they’re stupid.”
— Letter to Editor of Oroville Mercury Register, 6/23/19
Park in the first open spot or chance one opening much closer?
Posted by mark in pop, Uncategorized on June 6, 2019
Up until a few years ago when going to an event with limited parking, I always took the first opening available. But then one of my buddies told me how he prays for a closer place and one always opens. I thought about that and came to an epiphany that, as a general rule, one may as well try for a parking spot as close as possible to the destination. That’s been working for me ever since.
This strategy is now validated by researchers who evaluated three alternatives: meek, optimistic and prudent. They mathematically disrespect the meek driver parks at the first available spot that is behind the most distant parked car.
“The meek strategy is the most stupid strategy.”
Professor Sidney Redner, Santa Fe Institute—co-author of Simple Parking Strategies, Apr 14, 2019
However, the optimistic driver (like my prayerful friend) who goes for the closest spot, bypassing any gaps before the destination, pays a big penalty if they fail–going all the to the back of the parking line and being late for their even. It is better to be prudent—the middle strategy—by parking at the first gap.
Being methodical and frequently searching for parking at sporting events, I am very appreciative of this analysis. It reinforces my new-found faith (thanks to my friend) that the meek do not inherit the earth, at least not a good place to park your car.
ASA calls for abandoning the declaration of results being “statistically significant”
Posted by mark in Basic stats & math, Uncategorized on May 1, 2019
On March 21 the American Statistical Association (ASA) sent out a shocking email to all members that the lead editorial in a special, open-access issue of The American Statistician calls for abandoning the use of “statistically significant”. With irony evidently intended by their italicization, they proclaimed it “a significant day in the history of the ASA and statistics.
I think the probability of experimenters ignoring ASA’s advice and continuing to say “statistically significant” approaches 100 percent. Out of the myriad of suggestions in the 43 articles of The American Statistician special issue the ones I like best come from statisticians Daniel J. Benjamin and James O. Berger. They propose that, because “p-values are often misinterpreted in ways that lead to overstating the evidence against the null hypothesis”, the threshold for “statistical significance” of novel discoveries require a threshold of 0.005. By their reckoning, a p-value between 0.05 and 0.005 should the be degraded to “suggestive,” rather than “significant.”*
It’s a shame that p-hackers, skewered in this xkcd cartoon, undermined the sound application of statistics for filtering out findings unsupported by the data.
*The American Statistician, 2019, Vol. 73, No. S1, 186–191: Statistical Inference in the 21st Century, “Three Recommendations for Improving the Use of p-Values”.
Money buys happiness unless you get caught up in the Easterlin paradox
Posted by mark in Uncategorized, Wellness on April 23, 2019
The March 23rd issue of The Economist provides an interesting graphic on GDP per person—a measure of wealth—versus self-reported happiness. Overall it shows an upward trend that increases life satisfaction by 0.7 points (on a 10-point scale) as GDP doubles.
China is a prime example of money buying more happiness. Sadly, us citizens of the USA (and many European countries) are subject to the Easterlin paradox, which puts a limit on how satisfied people get as their income rises, beyond which money cannot buy more happiness.
Check out this interactive online version of the happiness vs wealth posted by The Economist. There, if American, you will see with some satisfaction (misery liking company) that Netherlands and several other wealthy countries share our downward trend. However, Germany and Britain remain on the upswing. (I wonder with Britain now in the throes of Brexit if their GDP will shrink and, if so, suspect that their happiness will also fall off.)
So, bottom line, for those of us stuck in the paradox, would you rather be richer or happier? That is a tough question!