Archive for category Uncategorized
Sleep well or get fat
Posted by mark in Uncategorized, Wellness on November 10, 2015
It’s not often I see a study that focuses on variability but that is what drives this recent New York Times story detailing how “Poor Sleep May Spur College Weight Gain.” Sleep for Science Lab researchers kept track of how 132 first-year students at Brown University slept over a nine week period, during which more than half of them gained nearly six pounds. The increase in weight comes as no surprise (one subject gained 18 pounds!) but this correlating to deviations in sleeping times is provocative. Whether this is causal, or just an offshoot of other upsets in lifestyle that come when students break loose from their parents, remains to be seen in controlled experiment.
Meanwhile, the National Sleep Foundation (NSF) widened ranges earlier this year (2/2/15) in these new recommendations in hours per day broken down by age:
- Newborns (0-3 months): 14-17 (previously 12-18)
- Infants (4-11 months): 12-15 hours (14-15)
- Toddlers (1-2 years): 11-14 hours (12-14)
- Preschoolers (3-5): 10-13 hours (11-13)
- School age children (6-13): 9-11 hours (10-11)
- Teenagers (14-17): 8-10 hours (8.5-9.5)
- Younger adults (18-25): 7-9 hours (new age category)
- Adults (26-64): 7-9 hours (no change)
- Older adults (65+): 7-8 hours (new age category)
My interpretation of all this is to get your teens to follow a fairly regular schedule for sleep (good for those of all ages, I feel sure), but don’t worry too much about the exact amount, provided it falls within the recommended guidelines of NSF.
P.S. In this report published November 4 in Sleep Review, Russell Foster, professor of circadian neuroscience at Oxford, recommends you brush your teeth in the dark to ensure a good sleep. That gives me a bright idea: glow in the dark toothpaste! 🙂
Breaking free of standard practices that no longer make sense
Posted by mark in Consumer behavior, Uncategorized on October 20, 2015
Building off my previous blog on “Why no one wants to monkey around with how things have always been done” I am passing along an insightful anecdote by David Morganstein, President of the American Statistical Association, about his wife’s standard practice to slice a quarter inch off of every ham and toss it in the trash. Read this amazing story and others like it in “The Slice of Ham, How Do You Know?”.
Most of our assumptions have outlived their uselessness.
– Marshall McLuhan, famed for predicting the World Wide Web almost thirty years before it was invented.
Achieving a good group photo in more than a blink of an eye
Posted by mark in pop, Uncategorized on August 16, 2015
This summer has featured a number of occasions where I got roped into a group photo, always enduring an annoying number of “just one more” shots. With this in mind, a retrospective in September’s Popular Science on the 25th anniversary of the Ig Nobel awards caught my eye by calling out the 2006 Mathematics award. This honor went to two Australian researchers who calculated that, for group photos of 20 or fewer people, you must divide the count by three and take that many photos to ensure that everyone’s eyes will be open.
Check out what to do if there are more than 20 in your group, noting that things become hopeless beyond a count of 50, and the underlying statistical calculations detailed in “Blink-free Photos, Guaranteed,” Nic Svenson, Australasian Science, August 2006, p48.
Upon accepting the award for frivolous research, the lead scientist, physicist Piers Barnes, said that
“We are proud to have made a gross simplification of complex physiological and psychological factors backed up with no empirical data. Like many other theories, if enough assumptions are made, we are confident that our expression holds.”
(Source: This phys.org press release.)
Picking on P in these times of measles
Posted by mark in science, Uncategorized on February 3, 2015
Randall Munroe takes a poke at over-valuers of p in this XKCD cartoon
Nature weighed in with their shots against scientists who misuse P values in this February 2014 article by statistics professor Regina Nuzzo. She bemoans the data dredgers who come up with attention-getting counterintuitive results using the widely-accepted 0.05 P filter on long-shot hypotheses. A prime example is the finding by three University of Virginia finding that moderates literally perceived the shades of gray more accurately than extremists on the left and right (P=0.01). As they admirably admitted in this follow up report on Restructuring Incentives and Practices to Promote Truth Over Publishability, this controversial effect evaporated upon replication. This chart on probable cause reveals that these significance chasers produce results with a false-positive rate of near 90%!
Nuzzo lays out a number of proposals to put a damper on overly-confident reports on purported scientific studies. I like the preregistered replication standard developed by Andrew Gelman of Columbia University, which he noted in this article on The Statistical Crisis in Science in the November-December issue of American Scientist. This leaves scientists free to pursue potential breakthroughs at early stages when data remain sketchy, while subjecting them to rigorous standards further on—prior to publication.
“The irony is that when UK statistician Ronald Fisher introduced the P value in the 1920s, he did not mean it to be a definitive test. He intended it simply as an informal way to judge whether evidence was significant in the old-fashioned sense: worthy of a second look.”
Statistic of the year: Americans busy buttering up
Posted by mark in pop, Uncategorized on December 31, 2014
According to today’s Wall Street Journal, USA citizens on average consumed 24 sticks of butter in 2014. Wisconsinites would be careful to differentiate whether this was really “butter” or actually “oleo”—aka margarine. By State law* restaurants will only serve the non-dairy “yellow stick from Satan himself” (as a Governor deemed it) if a customer specifically orders it. Until 1967 margarine was not allowed to be sold at all in Wisconsin—it had to be smuggled in from Illinois. Meanwhile in Minnesota only sickly white oleo could be purchased. To make it look buttery consumers had to knead in a capsule of yellow food color. I remember those days and my wife Karen recalls going on smuggling runs for pre-yellowed margarine from Iowa. Those were some messed up times!
Butter, preferably from grass-fed cows (margarine being ‘udderly’ eschewed), is now the rage as a health food thanks to The Cult of the Bulletproof Coffee Diet. At up to 2 tablespoons of this bovine grease per cup I presume 2015 will see an increase in per capita consumption. Yuk! These are some messed up times!
*See this detailed along with other strange Wisconsin State laws here.
Extreme brews and better ones that stay within more-reasonable limits
Posted by mark in pop, Uncategorized on October 26, 2014
While in Antwerp last week I sampled many good beers but none as good as the Trappist-brewed Orval pictured.
The locals love it so much that demand far exceeds supply from the ever-shrinking ranks of monks who brew it at the monks at the centuries-old Abbey of Notre Dame d’Orval. It is lip-smacking good, or as the Belgians in this Dutch-speaking region say—smakelijke.
On the flight home I watched several episodes of Brew Dogs, which features a pair of zany Scots who go for extreme craft beers. For example they took a blond Belgian ale and freeze distilled it many times to a level of 55 percent alcohol by volume (ABV)—a new record for beer. However even with it being infused with nettles from the Scottish Highlands and fresh juniper berries, this over-the-top brew must go well beyond the bounds of good taste.and … then put in a bottle created by a taxidermist.
A few years ago I headed over the border to Hudson, Wisconsin* to pick up a bottle of the then record-holder for ABV at a now-paltry 22 percent**—Dogfish Head’s World Wide Stout. With some coaching from my number one son, I poured it into a brandy-glass and sedately sipped it. I rate it zeer smakelijke. However, I am happy to go for far more reasonably high ABVs of 8 percent or so that come with tripel Belgian abbey ales. A few mugs of that provide a very good buzz. Proost!
*Many great beers do not achieve distribution in Minnesota due to liquor not being allowed for sale on Sundays and especially not growlers of craft-brews—all this being defeated again in May by State Senate. It seems that hell will freeze over and the Vikings will win the Superbowl before we can drink on Sundays. Until then it’s on Wisconsin.
**See this beer well down the BeerTutor.com list of strongest beers in the world.
Design of experiments (DOE) most important for optimizing products, processes and analytical technologies
Posted by mark in design of experiments, Uncategorized on March 1, 2014
According to this February 2014 Special Report on Enabling Technologies two-thirds of BioProcess readers say that DOE makes the most impact on their analytical work.
“The promise of effective DOE is that the route of product and process development will speed up through more cost-effective experimentation, product improvement, and process optimization. Your ‘batting average’ will increase, and you will develop a competitive advantage in the process.”
–Ronald Snee
The rarest of birds—a reproducible result from a scientific study
Posted by mark in science, Uncategorized on February 3, 2014
In The New York Times new column Raw Data, science writer George Johnson laments experimenters
“ways of unknowingly smuggling one’s expectations into the results, like a message coaxed from a Ouija board.”
– Science Times, 1/21/14
This, of course, leads to irreproducible findings.
As a case in point, only 6 of 53 landmark papers about cancer found support in follow up studies, even with the help of the original scientists working in their own labs, according to an article in the Challenges in Irreproducible Research archive of Nature cited by Johnson.
That is discouraging but I am not surprised. I feel fairly sure that the any assertions of import get filtered very rigorously until only ones that reproduce reliably make it through.
The trick is to remain extremely skeptical of initial reports, especially those that get trumpeted and reverberate around the popular press and the internet. Evidently it is human nature to then presume that when an assertion is repeated often enough then it must be true, even though it has not yet been reproduced. Saying it’s so does not make it so.
Boo Yahoo for breaking bad on my MAD
Posted by mark in sports, Uncategorized on November 20, 2013
“Once is happenstance. Twice is coincidence. Three times is enemy action!”
— Ian Fleming
, Goldfinger
A simple, yet effective, measure of forecasting prowess is the mean absolute deviation (MAD). Yahoo’s computer projections for fantasy football do poorly on this measure. For example, one of my teams is thus far, through the first 11 weeks of this season, at 16 points MAD from an average projection of 70 per game. That’s an error exceeding 20%! But to make matters far worse, their forecast on this team is terribly biased. Given my indignation you can guess which way Yahoo has been erring (yes, I am a loser)—consistently over-estimating how points my players actually accumulate. Enough data has come in to make this statistically significant as indicated by the confidence interval on the margin of error (MOE) being below zero. Between my fantasy team and the Vikings it’s hard to say which is doing worse at underachieving. Thank goodness for the Minnesota Gopher gridioners exceeding all expectations. That is a ray of sunshine in a gloomy Fall for a football fanatic like me.
Quants and nerds bring science and reason to the dark fortress of superstition
Posted by mark in sports, Uncategorized on November 2, 2013
Alison Gopnik, The Wall Street Journal’s “Mind & Matter” columnist, goes a bit over the top today while paying homage to baseball’s statisticians. But one must be mindful that she teaches at U Cal Berkeley—less than 15 miles from the home field of the Oakland Athletics and “Moneyball” wizard Billy Beane. At the other end of the country the Boston Red Sox rule supreme in Major League Baseball in large part to calculations by their adviser Bill James—inventor of sabermetrics: the empirical analysis of baseball, especially statistics that measure in-game activity.
However, BoSox hero (one of many!) Jonny Gomes, who got a lot of disrespect for his measures—yet came through in the clutch, came back with this shot in an on-field interview with FOX Sports’ Ken Rosenthal after the clincher at Fenway Park:
“There’s a lot of sabermetrics, there’s a lot of numbers and stuff. The whole WAR stat. But when you go to playoffs, you want me to go to war with.”
WAR stands for Wins Above Replacement. The Red Sox led MLB on this statistic as shown here. Gomes only rated a bit over 1 on WAR. A “solid starter” should achieve a WAR of 2 or more according to this white paper by Boston’s Yawkey Report.
It’s hard to argue with success, but take that Jonny!