Sunday, July 20, 2014

High-School Crushes - Anylysed Mathematically!

John Paulos considers some statistics relevant to romantic crushes.
The second relevant statistical notion is Bayes’s theorem, a mathematical proposition that tells us how to update our estimates of people, events and situations in the light of new evidence. A mathematical example: Three coins are before you. They look identical, but one is weighted so it lands on heads just one-fourth of the time; the second is a normal coin, so heads come up half the time; and the third has heads on both sides.
Pick one of the coins at random. Since there are three coins, the probability that you chose the two-headed one is one-third. Now flip that coin three times. If it comes up heads all three times, you’ll very likely want to change your estimate of the probability that you chose the two-headed coin.
Bayes’s theorem tells you how to calculate the new odds; in this case it says the probability that you chose the two-headed coin is now 87.7 percent, up from the initial 33.3 percent.

Thursday, July 10, 2014

The Big Picture of the Summer Job
 It looks like summer jobs are harder to get than they used to be. It's not just the recession. That was 7 years ago.
So what explains the trend? Are kids today lazy? Do they feel unprepared? Is minimum wage pressure pushing the lowest skill workers off the bottom? Are students competing with China or adults (who are competing with China?) This is US data. Is it competition from low-skill immigration?

Wednesday, June 25, 2014

This Summer's Assignment

School can be a good environment to learn academic skills like arithmetic, algebra, geology, grammar, history and essay construction. It is a lousy place to learn how to use your academic skills. That is an executive function.

Your education doesn't stop this summer. Develop those critical skills. Go play.

Monday, June 23, 2014

It's a Show...It's an Education...It's Dinner keeping with my easily distracted interest in cooking, let me speak of the Culinary Training Studio.
It looks like a kitchen surrounded by a bar. It has been described as being part of your own cooking show. You might call it a cooking class where you don't have to work and get to eat the food. Or you might call it a six hour dinner, with entertainment in the form of food talk.

Wednesday, June 18, 2014

Global Warming From a Sunnier Globe
What if pollution makes the planet cooler? That's what made the most sense to me when I first thought about the issue. (I think it was grade 2 that I had noticed that clouds make it cooler and my teacher told me that pollution causes clouds.). You'd think someone would have looked into this earlier.

It turns out that pollution does block the sun. The planet's mid-century cooling (from the 50's to the 70's) is explained by the blockage of the sun. The late century rise in temperatures is explained by pollution reductions.

Plus, clarity from the comments:
"If i get this right, industrial pollution masked the natural warming from the Little Ice Age and the clean air initiatives caused the earth temperatures to rebound to normal levels." - Lawrence Todd

Wednesday, June 11, 2014

Environment Leaping Forward, If...
The earth's natural environment keeps getting better at supporting life, especially human life.Thanks to new technology we are about to make major progress in carbon emissions, medical science and relief for the poor. The progress would be felt first on this continent. Then, once the technology is common and established, it will be practical for the third world as well.

The problem is that there is an entrenched group of influential and politically connected people who, fearing a loss in their current privilege, obstruct progress.

Friday, May 23, 2014

Life on Mars Confirmed!
Well, life on Mars very likely, anyway...but it is probably dead by now...and we brought it.

Meteor Shower Tonight
That is, just after midnight, Friday, May 23 (aka early morning May 24) There will be a meteor shower called Camelopardalids. Look north. The meteors will appear to originate from just north of Polaris (the North Star).

Friday, May 9, 2014

Saturday, May 3, 2014

Science of Color
Studies on color and tests of people's reactions have intriguing results:
For instance, the study into the psychological effects of pink, mentioned above, was carried out by Alexander Schauss in the Seventies. It showed that of 153 male prisoners put in cells painted pink, 98.7 per cent were weaker after being in the pink cells for only 15 minutes
Of course, there is the practical application, selling people stuff:
...a paper in the Journal of the Academy of Marketing Science, ... White is “purity, cleanness, simplicity, hygiene, clarity and peace”; black is “sophistication, glamour, status, elegance, richness and dignity”. Purple is status, pink is femininity, and, of course, blue suggests competence while red is exciting.
and speculation on why we humans see color at all:
...developed the ability to detect the colour red because of a common characteristic: bare-skinned faces. Suddenly, we could “read” the all-important expressions of anger, dominance and sexual readiness on the faces of those around us.

Tuesday, April 22, 2014

Questions to Ask a University

Universities have a reputation as havens of expanded minds and stimulating thinking. They can be. They can also be among the most closed, fearful places in contemporary North America. If you are interested in your university getting these issues right, here are some questions to ask.

Saturday, March 29, 2014

Making a Lush, Green Planet
Increased CO2 is helping plants grow around the planet. It seems that there are two effects at play. CO2 is good for plants, a type of fertilizer. CO2 also helps plants use water more efficiently. A third effect of CO2 is on rainfall. This one is so far unresolved: many models (and nearly all the press) predict that a hotter planet will be dry. Others (and the evidence so far) say that warmer means wetter. Beyond dispute, is that so far the increase in carbon has correlated to a greener planet.

Monday, February 17, 2014

Friday, January 24, 2014

That's Not an Explosion...

There is a supernova happening in the neighborhood. Actually, it happened about 12 million years ago but we get to see it now, for a couple of weeks. It seems like a busy neighborhood.

Sunday, January 12, 2014

Cheap Digital Microscope has plans for a lens and stand that lets you use your smartphone as a digital microscope. They claim up to 175x magnification (with two lenses, up to 375x!) That is enough to look at onion cells. This is a maple seed pod at only 60x.

Project cost: $10

Saturday, January 11, 2014

Brown Dwarfs Detected

A brown dwarf is not like a white dwarf: on the death march of a real star. A brown dwarf is a star too small to kickstart full fusion, too small to emit light, but big enough to emit energy (as infrared) for billions of years and fantastic enough to have liquid iron falling from the sky as rain. A Canadian team is using the Spitzer IR Space Telescope to study them.