Archive for category pop
Oh, oh—sociology professors say that “most of what we do for our kids at schools doesn’t matter”
Read this New York Times essay on why Parental Involvement Is Overrated and weep for all the time you spent helping your child become well-educated. It doesn’t help that
“most parents appear to be ineffective at helping their children at homework.”
Many a time my kids asked me to help them do math, which I really dreaded—not because I could not come up with the answer, but due to the constantly-changing way schools taught it. After being told many times that I got the right answer the wrong way and thus provided absolutely no help, I began bearing down on studying the latest-and-greatest math book first before working out the problem.
By the way, I made the student go through the materials with me—that made this an effective approach for parental mentoring, or so I thought. Now I wonder if I should’ve even bothered.
However, one time one of my daughters did say that my way of explaining a puzzling math problem made a lot more sense the either the teacher or the book. That’s one time out of hundred other times that my good deeds did not go unpunished, but like the single outstanding golf shot out of hundred bad ones in any-given round, I remember this fondly. 🙂
Fun trivia on how many people it takes before chances are good that some or all share birthdays
Birthdays are in the news this month as the last of the Baby Boomers hit age 50—most notably Michelle Obama, but also my youngest sibling—brother Paul. A little game I’ve played with my larger statistics classes is to poll them for their birthday—month and day (one mustn’t dare to ask for the year). It turns out that with 23 people coming together at random the odds tilt in favor of at least two sharing this special date. Somehow that just does not seem likely but all one needs to do for working this out is calculate the probability of all having different birthdays, and then subtract the answer from 1.
By the way, it takes 88 people to achieve a good chance of 3 sharing a birthday.
This last statistic (88 for 3) comes from statistician Mario Cortina Borja in an article he wrote for the latest issue of Significance detailing “The strong birthday problem,” that is, not just one person but everybody in a group sharing a birthday with at least one other. By assuming that the birthdays follow a uniform distribution,* Borja worked out this complex problem. His results are somewhat counter-intuitive in the way probabilities decrease from 2 to 365 and rise thereafter—quickly gaining at 2000 and beyond. (Of course if only “me, myself and I” are gathered, that is, one person, the probability is technically 100 percent of a birthday match.) The answer to this strong birthday problem is 3064. At 4800 people there’s a 99% chance that everyone will share a birthday with another.
Borja suggests that it might be fun for a large celebration to award a prize to anyone with a lone birthday. If one won such a contest, it would really be a lonely experience.
*P.S. Borja provides the math for birthdays being distributed non-uniformly, but leaves it at that because the computational cost of solving it is “fiendish.” That’s OK because other statisticians who studied this problem found that the results change very little with deviations from the uniform distribution.
Another round of three deaths now underway—triggered by the Professor
My favorite character in Gilligan’s Island–the Professor (aka Dr. Roy Hinkley)—passed away recently. 🙁 Who else will die, I wonder, because these always come in threes, or so it seems.
According to this newly-published study explaining “When Three Charms…, people gravitate to number 3. Being business school profs (Suzanne B. Shu of UCLA and Kurt A. Carlson of Georgetown U.), the authors focused on how to exploit this phenomenon for marketing purposes—their experiments pointing to the power of persuasion being optimized at three claims and no more—the fourth one pushes consumers over to being over-sold.
So be on guard from now on whenever someone tries to sell you on something by touting three reasons. 😉
Getting back to the morbid fascination with celebrity deaths, it may just be that this occurs from the natural tendency to conclude that three events in a row cannot happen just due to chance.
“You reach maximum streakiness at three events.”
– Kurt Carlson quoted by New York Times in 1/3/14 article about The Power of Three
Being somewhat savvy on statistics and generally a rational thinker, I know this is immensely overblown, but I cannot help but succumb to it, in particular when bad things come in bunches. My trick to put a halt to being unlucky is to resolve that whenever I’m hit by three unpleasant events then I watch for three good things to come. I suppose this is just the power of positive thinking overcoming the depressive impact of cursed karma, but this works for me—I encourage you to give it a try.
When the bunch of bad reaches three, that’s it for me–make that your mantra. 🙂
Statistics for good (per year-long celebration) or bad (as many still feel)
“As with a knife in a surgeon’s hands, it can save a life, but it could also kill someone, in the hands of a crook.”
— Sastry Pantula, Dean of the College of Science, Oregon State University
This quote caught my eye in yesterday’s Wall Street Journal article on “About 88% Through Year, 100% of Statisticians Find Field ‘Sexy’”—a recap of Statistics2013, which pays homage to the 300th anniversary of Jacob Bernoulli’s landmark book The Art of Conjecturing.*
My interest in statistics stems from a belief that one should live by what you see, not what supposedly should be. In other words, let the data speak. I have little patience for speculation based only on personal opinion, unless it comes from one who clearly possesses great subject matter knowledge—even then I would like to see peer-reviewed research supporting the contentions. The converse of this is being greatly off-put by people who obviously do not know what they are talking about using statistics as a weapon. This is crooked (as noted by Prof Pantula).
But never mind this dark side of statistics, it’s time to celebrate them as Gianluca Massimo and his Italian friends (including students in Statistical Sciences at the University of Padua) did in this ‘bromantical’ music video.
*For a scholarly review and historical context, see “The Significance of Jacob Bernoulli’s Ars Conjectandi for the Philosophy of Probability Today” by Glenn Shafer of Rutgers University.
Putting the cheeriest spin on 2013 World Happiness report by the United Nations
Kudos to Bloomberg Businessweek graphics editor Evan Applegate for this breakdown showing Peru on top for achieving the biggest percent gain in happiness over the past 5 years. One of my daughters moved to Arequipa this summer and started up an organic chocolatieria and coffee shop so I’ve no doubt that this is now the nexus of burgeoning bliss. 🙂
If you squint while taking a test will it improve your score?
In a 2007 experiment, researchers at Princeton split 40 math students into two groups for a test written up in two fonts—one clear and the other difficult (italic, light gray). Counter-intuitively the latter group scored 29 percent higher. In his new book David and Goliath, Malcolm Gladwell, renowned for the best seller the popular Outliers, cites this as an example of how “facing overwhelming odds produces greatness,” or, as Nietzsche said “That which does not kill us makes us stronger.” This works for me—being up for challenges, but perhaps it cannot be extrapolated to the people in general. As Christopher Chabris cautions in this Wall Street Journal review yestertoday, provocative results like the ones from Princeton often cannot be reproduced. He warns:
“Anyone who has followed recent developments in social science should know that small studies with startling effects must be viewed skeptically until their results are verified on a broader scale. They might hold up, but there is a good chance they will turn out to be spurious.”
If it seems too counter-intuitive to be true, perhaps it isn’t—best in these cases you await confirmation by others in adequately-powered verification experiments.
Tailgaters not put off by center high mounted stop lamps
Posted by mark in Consumer behavior, pop on September 12, 2013
According to National Highway Traffic Safety Administration (NHTSA) nearly a third of all crashes are rear-enders. So, when an experiment by psychologist John Voevodsky in 1974 found that San Francisco taxis equipped with a third brake light suffered 60.6% fewer rear-end collisions, it got the attention of the NHTSA. After replicating these results on a larger scale, they required center high mounted stop lamps (CHMSL) on all new cars in 1986. However, recent studies show a reduction in accidents of only 5%!*
I suppose drivers now are too busy texting to be deterred by CHMSL. ; ) But now Ford is experimenting on wirelessly warning those following when a driver puts the brakes on. See more details here. I suggest it set an alarm off on cell phones too—similar to wireless emergency alerts.
But the only real solution to rear-end collisions would be a system that automatically reduces speed on serial tailgaters. They are a menace to society in my opinion. Meantime let’s hope our highway patrols do what these cops did on California’s freeways.
*(Thanks to University of Minnesota Professor Sanford Weisberg of the School of Statistics for bringing this to my attention in his seminar today.)
Little correlation between pay and how meaningful you find your work
Posted by mark in Consumer behavior, pop, Uncategorized, Wellness on September 1, 2013
The August 26 issue of Business Week features this chart on median salary versus job meaning developed by salary comparison site PayScale. See if your profession is listed and, if so, how your colleagues rated their work.
I find it interesting that one of the lowest paying jobs—water treatment plant operator—came in at 100 percent self-rating of high job meaning. On the other hand, a securities trader makes twice the pay but only 14 percent felt their work meant much.
Neurosurgeons come out tops on both counts—salary and meaningfulness. That takes brains getting into a position like this. ; )
One of the least-paying jobs listed by PayScale is gas station attendant—it is also, evidently, nearly completely meaningless. It seems that a person stuck with this work would do well by becoming a dog kennel worker: The pay is about the same but carers for canines rates their job at 64% on the meaningful scale. My pet Penny (pictured sharing water with my grandson) approves. : )
Machine provides the perfect pour for Japanese beer
Awaiting a flight out of Japan’s Narita Airport, I came across this beer-pouring machine in the Delta lounge. See it in action here. It turns out that there’s a science to pouring beer as I reported in this article explaining how UK Boffins Pull Off Brilliant DOE on Beer. The only drawback of this machine is that it lacks conversational skills. I found it a bit awkward sitting there with my perfectly poured beer and no one to talk to while enjoying it. 🙁
Negativity about positivity
Every day for me is a battle to keep up the positivity and dampen down the negativity–I just feel better doing this, especially when others respond in kind. This news from The Scientist debunking the “positivity ratio” makes my goal easier–I need only aim to be on the plus side, even by a tiny little bit–not on a nearly 3 to 1 basis. 🙂
P.S. Being its now past noon on Wednesday we are over the hump on the work week. Cheers!