Archive for category science
Ivory towers of academia (& shiny ones in Vancouver)
Today’s Vancouver Sun suggests that a competitive university culture discourages sharing of knowledge, which then leads to the publication of many flawed and fraudulent studies. This is a rehash of issues I cited recently with the warning Beware of obvious answers and positive results. It would be great, albeit a bit boring, if journals published negative results from well-designed experiments with adequate power to see beneficial results. As my colleague Wayne Adams says
“Most of what you learn from an experiment is what NOT to do.”
PS. I took this picture Granville Island looking across to downtown Vancouver.
Marshmallows measure the speed of light (and get put to other good uses)
One of my favorite blogs, Flowing Data, provided me the heads-up on a great lecture by Adam Savage (the Mythbuster’s guy) called “Simple ideas lead to scientific discoveries”. I really enjoyed all of his stories, but especially the one on Hippolyte Fizeau’s measurement of the speed of light in 1849. Ingenious!
Coincidentally, my brother Paul forwarded me a detailing of how one can measure the speed of light with a tray of mini-marshmallows! Check it out at this Science Blog written by theoretical astrophysicist Ethan Siegel. This sharp-fingered fellow (if you view his blog you will see what I mean) goes on to tout a marshmallow-made diorama that ‘peeps’ recent claims of particles going faster than the speed of light.
That leads me to puffing up my daughter Emily, who achieved the “peeple’s choice” award in the Saint Paul Pioneer Press Ninth Annual Marshmallow Peeps Diorama Contest. She and two of her closest peeps produced The Mupeeps Take Minnepeepolis. It looks very much like the view out of my window from Stat-Ease headquarters east of downtown Minneapolis.
By the way, my favorite Muppets are Bunsen and Beaker. See them demo their invention of fireproof paper here. At the Muppets Lab one should always be prepared with fresh marshmallows on a stick. I advise going for two at a time. o——<8
Beware of obvious answers and positive results
Posted by mark in science, Uncategorized on March 4, 2012
“Most results, including those that appear in top-flight peer-reviewed journals, can’t be reproduced.”
This is a “dirty secret” revealed by the Wall Street Journal’s Gautam Naik in this December report. It cites statistics from Bayer that nearly two-thirds of published studies could not be replicated. Naik blames the complicated nature of experiments nowadays along with the “positive bias” researchers driven to produce results. Glenn Begley, vice president of research at Amgen, a biotechnology company, suggests that “academic scientists, like drug companies, should perform more experiments in a ‘blinded” manner to reduce any bias toward positive findings.”
Meanwhile, Duncan Watts, author of Everything is Obvious: *Once You Know the Answer says
“When you do the experiment properly [randomized and controlled], all the numbers go down.”
He’s speaking on the bias of marketing executives toward their own sensibilities, which often do not reflect those of the population being sold to. See what the Financial Times “undercover economist” Tim Harford says about this here. Unfortunately, in my experience, those (the analysts) who know better than to extrapolate from small, non-representative sample of opinions from the ‘powers-that-be’ (often n=1, that is—the Boss) get very little support for spending money to put these assertions to the test. Even though you know the top dogs might be barking up the wrong tree it’s easiest just to go along with the pack and press ahead. To do otherwise risks suffering a painful bite-back. Yes, I am a cynic.
Speed of light exceeded (astounding!)? Or was it measurement error?
This morning I read this NY Times news that European physicists measured neutrinos at 0.0025 percent above the speed of light. If so, it may be only a matter of time before you can send yourself a telegram to not do whatever you did that you’ve always regretted and, by the way, to please invest a thousand dollars in Microsoft, Facebook or the like (depending on the timing).
Years ago I visited Mount Wilson Observatory in California with my son Hank. See me pictured by their two domes that house 60 and 100 inch telescopes; respectively. This was the center for landmark experiments on the speed of light as detailed in this Wikipedia article. Obviously measurement error made this a very difficult.
Being a skeptic, and seeing that a similar experiment* found neutrinos whizzing about at the speed of light, but not beyond that, I was going to advise caution. However, Hank gave me the heads up to today’s xkcd cartoon (click the image to make it bigger and more readable). I think this guy has got a better idea.
*Done with a group at the Soudan Underground Laboratory here in Minnesota. They first did physics experiments there, in an abandoned iron mine, in 1980. I featured this in a retro young-adult techno/adventure/mystery/thriller called The Secret of the Wolf Ring (Amazon, Kindle Edition).
Eggs-plosion in the aftermath of Easter
Posted by mark in science, Uncategorized on April 30, 2011
I’ve become accustomed to hard-boiling an egg for my breakfast so I was pleased to see a surplus of Easter eggs after celebrating this holiday last Sunday. My dexterity for shelling eggs is not a-pealing (ha ha) so I decided to try an eggs-periment: Microwave an Easter egg just long enough to heat it up and loosen it up for eggs-traction. If I’d have quit after my first try of 15 seconds, I may’ve succeeded. But the egg just didn’t feel hot enough so I added more time. Kapow! The eggs-plosion left nothing more than a millimeter of shell intact. The uniformity of organic matter throughout the inner surface of the microwave oven was very interesting, I think – quite impressive.
Although I consider this to be a very successful experiment, it’s one that I don’t feel needs to be replicated. My colleagues at Stat-Ease have provided a number of suggestions for another eggs-periment such as boiling the Easter eggs in vinegar or baking them. This creates a looser shell, they say.
Feel free to provide other ideas, but keep in mind that disaster seems to lurk behind me whenever I try an experiment. My failures tend to be quite spectacular. But, on the other hand, that’s what makes experimentation so eggs-citing!
Kitchen pantry science – fun experiments to do at home
Several months ago I watched a neat demonstration by kitchen-pantry scientist Liz Heinecke on how to write secret messages. All you need are cranberries, water, baking soda and some paper as detailed here. Liz, a mother of three, provides many fun experiments (“simple recipes for real science”) to try at home. I think it’s a great way to get kids interested in science. However, be forewarned, she’s got a masters degree in bacteriology so some of her ideas might grow on you. ; )
This reminded me of a parent who worked as a microbiologist for the FDA. She did a show-and-tell for a Cub Scout den that I led 20 years ago. One of her items collected from FDA was a can of vichyssoise (leek-potato-onion soup traditionally served cold). It had been tested positive for botulism. We were told that if opened, this container of bacteria could sicken all of the inhabitants of New York City. After hearing this, I vowed to always boil canned soup.
Science can be as easy as baking. I want to encourage parents to open up their kitchen cabinets, stir up some science with their kids, and feed those hungry minds.
— Liz Heinecke, kitchen-pantry scientist
Statistics-driven scientific methods slammed again
This December 13 article published by The New Yorker adds fuel to fire for deemphasizing significance testing as the criterion for accepting purported advancements in science. It’s well worth reading for anyone with a stake in statistics, despite raking over the same coals seen in this March 27 Science News article, which I discussed in a previous blog.*
“A lot of extraordinary scientific data are nothing but noise.”
– Jonah Lehrer, author of “The Truth Wears Off: Is there something wrong with the scientific method”
Evidently much of the bad science stems from “significance-chasers” – those who hunt out findings that pass the generally-accepted p-value of 5% for hypothesis testing. Unfortunately a statistically-significant outcome from an badly-designed experiment is of no value whatsoever.
PS. I credit blogger William Briggs for bringing this article to my attention. His attitude is provided succinctly by this assertion: “Scientists are too damn certain of themselves.”
*Misuse of statistics calls into question the credibility of science March 28, 2010.
A fruit fly by any other name is still a fruit fly
A good example of what South Korean educational system produces (see my previous blog) is their first astronaut, bioengineer Yi So-yeon, who was featured in this article Tuesday by The Korea Herald . During her mission at the International Space Station she completed a number of experiments, including one that involved the assistance of 1000 fruit flies.
If I were an astronaut going up with so many flies, I’d shake the container just before lift-off to get them up in the air and lighten the load. I heard about this trick from my next-door neighbor – a bee-keeper. He loaded up too many hives in his truck and it went over-weight, but he beat the inspectors by banging on the side with a hammer as he drove onto the scale.
Having segued to bees, here’s a heads-up about a study done by a group of 8- to 10-year-old British school children from Blackawton Primary School. They trained a bunch of bees to go to specific-colored and/or patterned targets by selectively rewarding them with sugar. This experiment met the standards of the Royal Society, which published the results in this Biology Letter. Also see these kind comments. Wired Science provides a ‘dumbed-down’ version with photos, that is, an executive summary 😉 here.
“We discovered that bumble-bees can use a combination of colour and spatial relationships in deciding which colour of flower to forage from. We also discovered that science is cool and fun because you get to do stuff that no one has ever done before.”
– Children from Blackawton
PS. Some folks think that drosophila melanogaster is a misnomer for this little critter that mysteriously spring up from discarded apples and the like. “The fruit fly’s name is likely to change to Sophophora melanogaster if results of a new evolutionary analysis are accepted” according to this April 2010 bulletin from the International Commission on Zoological Nomenclature. Who made them lords of the fruit fly?
Reaching your boiling point
Our marketing director emailed me this motivational video called “212° the extra degree.” this motivational video called “212° the extra degree”. It says that at this temperature water boils providing the steam needed to accomplish things. The idea is that only one degree of heat makes all the difference.
I get it. However, being a chemical engineer with an interest in being accurate about physical processes, I had to be troublesome by pointing out that here in Twin Cities at over 800 above sea-level the pressure drops enough that on average the boiling point drops to 210.5 F. But setting this aside and focusing only on the 1 degree between water and steam, one must keep in mind the huge difference of simply heating up water versus making it change state, the is, the heat (or enthalpy in technical terms) of vaporization.
Thank goodness that our marketing director had become accustomed to working with a bunch of engineers, statisticians and programmers who, when one asks “Could I talk with your for a minute?”, immediately set the timer on their digital watches for precisely 60 seconds (the the nearest one-hundredth).
Coincidentally, while vacationing in Wisconsin’s Door County, I enjoyed a fine demonstration of how hard it can be to bring a quantity of water to a boil. It’s a tradition there to throw a bunch of fish in one kettle and vegetables in another and cook them up with a wood fire. However, as I learned and experienced from a somewhat dangerous vantage point, a pitcher of kerosene provides the final heat needed to accomplish the boil-over. My eyebrows needed a bit of burn-back, so that’s OK.
Misuse of statistics calls into question the credibility of science
Posted by mark in science, Uncategorized on March 28, 2010
The current issue of Science News features an indictment of statistics by writer Tom Siegfried. He pulls no punches with statements like this:
“…a mutant form of math has deflected science’s heart..”
“Science was seduced by statistics…”
“…widespread misuse of statistical methods makes science more like a crapshoot.”
“It’s science’s dirtiest secret: …testing hypotheses by statistical analysis stands on a flimsy foundation.”
“Even when performed correctly, statistical tests are widely misunderstood and frequently misinterpreted. As a result, countless conclusions in the scientific literature are erroneous…”
Draw your own conclusions on whether science fails to face the shortcomings of statistics by reading Siegried’s article Odds Are, It’s Wrong.
My take on all this is that the misleading results boil down to several primary mistakes:
- Confusing correlation with causation
- Extrapolating from the region of experimentation to unstudied areas
- Touting statistically significant results that have no practical importance
- Reporting insignificant results from studies that lack power to see differences that could be very important as a practical matter.
I do not think statistics itself should be blamed. A poor workman blames his tools.