Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at secondhandscience@gmail.com with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Mathematics
What I’ve Learned:

Statistical significance: 'Do you feel 95% confident, punk?'
“Statistical significance: ‘Do you feel 95% confident, punk?'”

People are scared of numbers. Sometimes, the fear is justified. A 330 on your credit score report, for instance, is genuinely horrifying. So is a 410 on your SAT. Or anything greater than “two”, when asked how many cats your mother owns.

But most numbers are harmless. People only fear them because they might wind up in a statistic, and everyone is afraid of statistics. The saying is not “lies, damned lies and sharks with frickin’ laser beams”. It’s statistics. Even scarier than laser-sharks.

The problem is understanding. I can help — though only to a degree, because mathematics are involved, and I swore after memorizing the Pythagorean theorem that I was “full”, and couldn’t learn any more math.

(Which is probably why I’m familiar with the horror of subpar credit scores. And low SATs.

Someday, this will probably drive my mother to adopt a dozen cats. But not yet. Whiskers crossed.)

Happily, you don’t need math to demystify statistics; you only need to know about statistical significance.

(Although you might need a calculator or a fancy-ciphering web page to do some maths for you. Stand on the shoulders of Poindexters, my friend.)

Statistics can be manipulated to say just about anything — like a willing stool pigeon, or a guy trying to get a date with a lingerie model. The question is how confidently those stats say something, and that’s where statistical significance comes in.

Most scientists will run with a conclusion if they believe it’s at least 95% likely to be true. Some tests require 99%, and a few really crucial questions — like, can we clone Neil DeGrasse Tyson’s mustache in time for Halloween — need a 99.99% (or greater) probability before they’re accepted.

So how do researchers achieve those levels of confidence? Flip a thousand coins and see what comes up? Ask a Magic 8-Ball which answer is better? Co-author their papers with a pigskin-prognosticating porcupine?

(Based on recent scientific scandals, yes. A few of them apparently do.

But we try to weed these idiots out, based on their SAT scores. Or how many cats their mothers own.)

Real scientists determine statistical significance by performing calculations that take important factors into account, like the number of observations and the likelihood of the results.

For example, the “p-value” calculation, which involves math with Greek letters and squiggly brackets and other head-exploding details. But just remember it like this: the “p” in p-value stands for “pssshaw“, as in: “Pssshaw, you’re wrong; I bet your mom owns so many cats.

Once calculated, the p-value is the probability (subtracted from 1) that your scientific conclusion is full of smoking cat turds. A 1.0 means you’re one hundred percent talking out your ass, and a value of 0.05 means you can be 95% sure you’re not vocalizing through your rectum.

The keys to getting low — meaning good — p-values are making a lot of observations, and having most of those come out one way, and not the other. A million dice rolls where every number comes up just as often doesn’t tell you anything about what’s coming up next. And — to the chagrin of sportscasters everywhere — a winning (or losing) streak of one, two or eight games isn’t sufficient to make their pre-game blather “significant”. Or coherent, if there’s a liquor cabinet in the press box.

Another example: over the years, I’ve worked with a number of Belgians. From my observations, 100% of Belgians are named Paul, 100% wear fashionable sweaters, and 50% say really inappropriate things in the workplace.

Those are statistics, based on real observations — and some very uncomfortable staff meetings. But do the conclusions have any statistical significance? If the number of observations is ten million, sure. If the number is two (which it is), then no, more observations are needed. You should take these stats, and all others with low (or ambiguous) statistical significance, with a healthy grain of salt.

Also, a huge pile of kitty litter. But preferably not from your mom.

Image sources: ScienceNews (p-value roller coaster), Discovery/TLC (cat-wrangling mama), Daily Caller (“Watch out, guys; we’re dealing with a badass ‘stache over here.”), The Awl (8-ball uncertainty)

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· Categories: Physics
What I’ve Learned:

Gravity: what goes up... gets pretty complicated on the way down.
“Gravity: what goes up… gets pretty complicated on the way down.”

Gravity is a bitch. This is true for absent-minded skydivers jumping without their parachutes. But it’s also true for theoretical physicists. Because gravity doesn’t make much sense, and it doesn’t care who gets splatted on the ground trying to figure it out.

Gravity seems like it should easy. Everyone feels the pull of gravity — some of us more than we used to, and on body parts that have themselves “splatted” in shameful, horrifying ways. Discovering what’s underneath all that planetary tugging seems like a no-brainer.

But it is a brainer. A very big-brainer, actually.

Scientists recognize gravity as one of four fundamental forces of nature — and frankly, all four are pretty screwy. There’s the strong nuclear force, which may be mighty — but only works at scales smaller than atomic nuclei, so it’s also really tiny and sad. It’s the Rudy of universal forces.

Then there’s the weak nuclear force, which… I don’t know, holds the atoms of weak things together, maybe? Like that skinny kid in gym class, and Ikea furniture, and the Cleveland Browns. I’m just spitballing here.

Then there’s the electromagnetic force. Electromagnetism gives us light to see, radio waves to hear and microwaves to nuke our frozen burritos. It’s everywhere, and moves at the speed of light. Literally, because it is light, and various other wavelengths.

For all these forces, physicists have discovered corresponding elementary particles. Photons, for instance, which mediate the interaction of electric charges. The photons themselves are a pain to nail down — today they’re particles, tomorrow they’re waves — but at least we’ve found them. Likewise, particles called gluons carry the strong nuclear force, and W and Z bosons carry the weak force. It gets pretty complicated, but everything lines up and can all be explained by quantum mechanics.

Until you get to gravity. Because gravity is a bitch.

First of all, no one’s ever observed a particle — or wave, or aura, or Magic freaking 8-Ball — that carries gravitational force. There’s a predicted one, called a “graviton”, but we won’t be seeing those in a lab any time soon, because practical reasons.

(One estimate holds that we could detect one graviton every ten years, if we had a one hundred percent efficient detector the size of Jupiter. Which we don’t. And it only works if we put it near a neutron star, which we can’t. Also, it has to be shielded from cosmic neutrinos, which requires so much extra matter it would fall into itself and form a black hole. Which is bad.

In other words, gravitons are essentially undetectable. Eat your heart out, Higgs boson.)

We do have a shot at detecting gravitational waves, “ripples” in spacetime made up of many gravitons (if they exist) and produced by various astronomical objects. Some such waves may have been produced soon after the Big Bang, and may tell us something about the early origins of the universe. But we haven’t confirmed any discoveries yet, and interference from various electromagnetic sources on Earth make reliable detection tricky. (Stupid delicious microwave burritos.)

The other issue — theoretical gravitons or no — is you can’t jam the equations dealing with gravity into quantum physics. When you try, you wind up with infinities over here and irreconcilable differences over there and everything goes to hell. You might as well try getting Katie Holmes back together with Tom Cruise. It’s not gonna happen.

That leaves gravity as the “odd force out” — and mathematically speaking, completely separate from the rest of the universe. All sorts of strategies have been devised to pull this crazy loner back into the fold, including string theory, superstring theory and loop quantum gravity. So far, nothing (testable) has worked.

So if you’re planning to prank someone by getting them to jump out of a plane without a ‘chute, you’ve got a fair chance of convincing them gravity doesn’t really exist at all. Bonus if they’re a physicist working on quantum gravity — because at this point, they’ll probably want to jump.

Image sources: Physics Is Fun (“Curses!”), ILoveSkydiving.org (lounging jumper), CinemaSips (“Rudy! Rudy!”), Today’s Zaman (giggly Katie, tee-hee Tom)

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