Archive for category pop
Brain disturbers make folks smarter or dumber (believe it or not)
Based on the underpowered experimental designs by neuroscientists reported in my previous blog, I am skeptical of these new findings, but they are very intriguing, nonetheless:
- 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.
Educational system turned upside down by distance-based learning
Posted by mark in design of experiments, pop on April 14, 2013
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.
Statistics provide a decisive advantage to taking one route to work versus another
Posted by mark in pop, Uncategorized on April 7, 2013
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!
Statisticians break down March Madness brackets (and rule things in general)
Before the first round of NCAA basketball playoffs a number of pundits favored my Minnesota team to upset UCLA—one of the commentators before the broadcast last night went so far as to say they were a “lock”. Now I believe it. (They won.) However, I am doubtful they can beat Florida Sunday—gophers just do not stand a chance against gators. For a more reasoned breakdown on the odds for Sunday and beyond, see this bracket filled out superstar statistician Nate Silver for the New York Times.
People who can crunch data like Silver are in big demand these days according to Wall Street Journal Numbers Guy Carl Bialik in his column on March 2. The jobs site icrunchdata (very descriptive!) posted 28,305 openings for jobs in statistics and the like last month—up from 16,500 openings three years ago (I love data like this!).
It seems that number-herding nerds now rule, but there is a catch according to Dan Thorpe, senior director for analytics at Wal-Mart. He says that “the bulk of the people coming out [with statistics degrees] are technically competent but they’re missing the consultative and the soft skills, everything else they need to be successful.” So, which to do you prefer—good math skills (and lots of money) or an attractive personality (and many friends)? My advice is to aim for some of both.
Slugging down beer—which brew preferred by shell-less terrestrial gastropods
Inspired by my new web-based “Launch Pad” to the book DOE Simplified, PhD biologist Gaston Habets put his new statistical know-how to good use in his own backyard out in California by offering a choice of beer to the slugs eating up his garden.
Being a native of a cold clime I’d no idea how troublesome slugs could be until some years ago when my cousin in the Bay Area had me out to her place for dinner and asked me to help her gather up greens from the garden. The size of the slugs surprised me: The Pacific banana slug approaches a foot in length according to this New York Times science blog.
Given their gentle nature and top speed of 0.0055 miles per hour, one need not fear these slimy creatures. The only thing is that they eat up the gardens. So that sets the stage for the humane solution of sidetracking slugs with a bowl of beer. But which brew do they prefer? Gaston did his bit for the sake of garden science by setting out eight trays at specific locations around the vegetables and randomly pouring either Bud light or alcohol-free O’Doul’s. He repeated this experiment over four nights in a way that blocked out any differences in the nocturnal feedings.* The graphic shown here shows the outcome: By nearly a 3-to-1 ration slugs preferred Bud Light over the O’Doul’s. They did not get thrown off by the random location of the beer—the slugs found their favorite bars and bellied up.
*Gaston’s data showed a maximum slug count on Saturday night, but then they dropped off to a minimum on Sunday. My conclusion is that slugs party hearty. Who knew?
Slugs prefer Bud Light over O’Doul’s
P.S. It seems that slugs from coast to coast really do prefer Bud from what I see here.
Glass-shattering interaction of factors
Posted by mark in pop, Uncategorized on December 29, 2012
Last week (12/21) the Today Show broadcasted an alarming demonstration of Pyrex glass exploding after being subjected to certain combinations of conditions. See NBC News’ detailing here . As reported in this American Ceramic Society Bulletin , some scientists believe that changes to the material (replacing borosilicate with soda lime silicate) weakened the glass. However, makers of Pyrex disagree vehemently with these conclusions—see their side of the story here.
It turns out that hot Pyrex pans set directly on a wet or cool surface, such as a granite counter-top, undergo a sudden temperature change that produces some risk of it shattering. That strikes close to home for me, having re-done our kitchen (as is the style nowadays) with granite. Fortunately, being accustomed to plastic (Formica) countertops, I always put down cloth potholders before setting down the hot Pyrex pan. The take-home message is being careful not to subject Pyrex to rapid increases or decreases in temperature. See this site for safety instructions.
PS. On a lighter note (literally: too much sun) regarding heat and silica (main constituent of sand) see this New York Times news making it official that the hottest temperature ever recorded is 134 degrees F in Death Valley. They are pyre Rex.
Time to lighten up on homework?
Posted by mark in pop, Uncategorized on October 21, 2012
The Wall Street Journal’s Market Watch this Friday posted the data shown in this chart. For the 11 countries shown** you can see why WSJ seconds the call by French President Hollande to ban all homework.
Students would party hearty but this laissez-faire approach will not fly with those blessed with ambitious parents. Nevertheless the call for less homework, fueled by new data from the National Center for Education Statistics, reinforces other studies going back at least a decade.
It will be interesting to see what emerges as a consensus for a the happy medium on amount of homework assigned. Four hours per night seems way too much, especially at the 8th grade level.
Meta-analysis of hundreds of studies done on the effects of homework shows that the evidence supporting the practice is, at best, modest. Homework seems to be most useful in high school and for subjects like math. At the elementary school level homework seems to be of marginal or no academic value.
– Malcolm Gladwell
*See the report here
**I took out Saudi Arabia, whose result of 34% below average, given 11% being assigned over 4 hours of homework per night, fell far below even these very off-putting predictions–an outlier statistically.
Acknowledgment: Thanks to Devan Govender for alerting me to this issue.
Rock on with algorithms?
Posted by mark in pop, Uncategorized on October 2, 2012
I started off my career as an experiment designer before the advent of cheap calculators. Paying $400 for an HP unit that (gasp!) did logarithms went far beyond my wherewithal in 1974. That was roughly the tuition for one college quarter at University of Minnesota if memory serves. I managed to cover that cost plus room and board by working 24 hours a week washing pots and pans at a hospital kitchen. Those were the days!
Calculating effects from the two-level factorial designs I did that summer as an intern at a chemical research lab required a lot of hand calculations—many numbers to add and subtract. Thankfully a fellow named Yates developed an algorithm after these experiments were invented in the 1930s. Following his directions one could tally things up and even do check sums without having to think much. That’s what algorithms do—provide a recipe for solving problems.
As an engineer I have a healthy respect for algorithms, but my wife, who works as a preschool teacher, thinks this is geeky. For example, I admired the nerdy professor in the TV show “Numbers” that aired a few years ago. But every time he expounded on some algorithm that ingeniously saw the pattern of a serial criminal, she just laughed. Ironically she is now hooked on a show called “Person of Interest” that is based on predictive policing, that is, using algorithms to calculate a crime to come. That scares me!
According to a new book by Christopher Steiner titled Automate This: How Algorithms Came to Rule Our World (see this Wall Street Journal review) all of us had best be on our guard against seemingly clever ways to systematically solve problems. It seems that the engineers, mathematicians, programmers and statisticians who come up with these numerical recipes invaded Wall Street. They became known as the “Quants”—dominating the way stocks now get traded.
The problem with all this (even I have to admit) is that these systematic approaches to things take all the fun out of making choices. Do we really want algorithms to pick our soul mates, invest our money, etcetera? I am up for algorithms like Yate’s that quickly solve mathematical problems. A good example of this is the first known algorithm recorded on clay tablets in 2500 B. C. that helped Sumerian traders divvy up a given amount of grain equally to a varying number of recipients. However when things become capricious with many unknowns that are unknowable being thrown into the mix, I’d rather make my own decisions guided by wise counsel.
There is an elephant in the room whenever it comes to discussing computer algorithms, particularly highly automated ones. Almost all such algorithms are inaccurate. They are inaccurate for many reasons, the most important of which is that human behavior is fickle. The inaccuracy could be shockingly high.
– Kaiser Fung, author of Numbers Rule Our World
I really shouldn’t bring this up, but do you suppose certain politician might be spending a lot of money on algorithmic solutions to how they can win election? Do these algorithms have any qualms about turning their protagonists into nabobs of negativism? I do not believe that an algorithm has any heart, unfortunately. An algorithm is like Honey Badger—it just don’t care.
How to better your brain to make it think and retain
Buried in my file of fodder for blogs I re-discovered a heads-up from the New York Times on 1/21/11 that giving yourself a quick quiz after studying something once works better than going over and over it. The test-triggered active retrieval promoted meaningful learning by half in terms of how much students remembered a week later.
If you know something, or if you have stored information about an event from the distant past, and never use that information, never think of it, your brain is functionally equivalent to that of an otherwise identical brain that does not “contain” that information.
— Cognitive neuroscientist Endel Tulving quoted in this publication in Current Directions in Psychological Science of research on active retrieval by Jeffrey D. Karpicke of Purdue University
Coincidentally I just read this passage in “Brenner and God” by Wolf Haas, three time winner of the German Thriller Prize, which struck a chord about how the mind works in mysterious ways: “…just like a light that’s too bright can be bad for the eyes, so, too, can a mind that’s too awake be not at all good for thoughts…a half-asleep person can always outmatch an awake person by a long shot, no discussion.”
This happens with me when I am really wrapped up in a writing project or dealing with a very tough problem. Then I cannot sleep well as thoughts keep winding through my head. Often as I am nearly into a dream an answer comes to me. Then the only thing is to get up and write it down in the hopes that next morning it still makes sense. In any case, if I do not make a note, I then cannot sleep for fear of forgetting it. But surprisingly these ideas do usually hold up to the light of day, albeit not always terribly brilliant.
Does this happen to you too?
Polysci prof asks “Is Algebra Necessary”?
Posted by mark in pop, Uncategorized on July 29, 2012
I was appalled to see this titular question on the front of today’s (Sunday) New York Times opinion section. It came along with this sidebar quote:
There is no good reason to force students to master quadratic equations. Doing so holds them back.
That really riles me up, seeing as how these polynomials work so well for response surface methods (RSM) for process optimization. The author, Andrew Hacker–emeritus professor of political science at City University of New York, believes that, by making math mandatory, our educational system filters out talented scholars. As an alternative to hard-core number-crunching, he proposes the “exciting courses” in ‘citizen statistics’ such as the Consumer Price Index. His aim is “to treat mathematics as a liberal art, making it as accessible and welcoming as sculpture or ballet.”
I enjoy seeing statues and I admire the grace and athleticism of dancers; however, Hacker’s vision is for me dystopian. But so long as the educational system provides for a branching of those who like math versus the others who do not, then we get the best of all worlds. I agree–let’s not force algebra on those who abhor it.