4.28.2006

Tongue Sight?

Okay, this is one of the stranger things I've heard in a while.
By routing signals from helmet-mounted cameras, sonar and other equipment through the tongue to the brain, [military researchers] hope to give elite soldiers superhuman senses similar to owls, snakes and fish.

...

The device, known as "Brain Port," was pioneered more than 30 years ago by Dr. Paul Bach-y-Rita, a University of Wisconsin neuroscientist. Bach-y-Rita began routing images from a camera through electrodes taped to people's backs and later discovered the tongue was a superior transmitter. (italics mine)

...

In testing, blind people found doorways, noticed people walking in front of them and caught balls. A version of the device, expected to be commercially marketed soon, has restored balance to those whose vestibular systems in the inner ear were destroyed by antibiotics.
http://www.makeworkpay.org/ Enter in your pay on the far right and see how long it takes a Top 500 CEO to earn what you earn. It takes 10 hours for a CEO to earn what the average Wal Mart employee earns in a year, about $13,000. Not only do most CEO's earn $11 Billion a year themselves, Wal Mart also makes about that much in profit per year. Now I know you all already know all this, but I just had to say something because there are these Republican and Libertarian kids in my Government class and we always bicker about labor issues. Now no one can deny that there is something wrong with those figures, and that Wal Mart, and every other top company that makes that much in profit, can shell out a little more so their employees make more than a living wage, or maybe so they can ALL have health insurance, which Wal Mart only covers %22 of their employees, and not to mention the plan they give is ridiculous. Hell, what if some of those companies that outsourced paid them babies that are making our clothing AMERICAN wages because they are AMERICAN companies. I just can't get over this. Can anybody explain any possible economical benefits that can come from child labor? Or possibly how to stop this crap? I'm feeling really politically charged because we have been having guest speakers from every political party come in to government and talk to us, and today, we have the Socialist party. So hopefully that will go better than yesterdays speaker, from the Constitution party.

4.27.2006

Read Nothing Into This Post

So I was thinking about the e.p.t.® pregnancy test. They advertise it as 99% accurate. Now, this actually means that 99% of the time, if there is a sufficient concentration of a particular hormone, the mechanism will indicate a pregnancy.

What I can't locate, however is the rate of false positives- or, what percentage of the time an insufficient concentration of said hormone will indicate a pregnancy. This is critical information, because the actual probability of getting a false positive is not very intuitive.

The way you actually calculate the probability that you're pregnant given a positive result on a pregnancy test is to use conditional probabilities, or Bayes' Theorem.

We say that P(A|B) is the probability of A given B. So, the probability of being pregnant (call it preg) given that you observe a positive result (call it +) on a pregnancy test can be written P(preg|+). We calculate this probability... but to do so, we need the "accuracy," as Pfizer reports it. They observe a positive result (+) given a pregnancy (preg) with 99% probability. So P(+|preg) = 0.99.

We also need to know what the chance that you're pregnant is. In the U.S., there are about 14 births/1000 population (according to the CIA Factbook). Given that we have about 300M people, approximately 50% of whom are women, we can say that if you are a woman, your chance of being pregnant is approximately 2%. This is, of course, a rough estimate, but bear with me. That is, P(preg)=0.02.

Lastly, we need one piece of information I can't seem to find: what is the probability of getting a positive result given no pregnancy, or P(+|not preg)? Well, if we assume there's a 1% chance of such a reading, P(+|not preg)=0.01.

Now, the formula is: P(preg|+)=P(+|preg)P(preg)/P(+), where P(+) = P(+|preg)P(preg)+P(+|not preg)P(not preg). We can now calculate!

So, P(preg|+) = 0.99*0.02/(0.99*0.02+0.01*0.98)=0.67. Under these assumptions, there's only a 67% chance that you really are pregnant given you got a positive reading on the test! Holy crap!

So from what I can tell, then, the false positive rate had better be reeeeallly low if you want to trust your tests.

Unlikely Quantities

A Baker's dozen is 13. Presumably this is because bakers are either generous-possibly- or innumerate-unlikely, as they have to calculate proportions all the time. So I guess, then, that a Banker's dozen is 11. This is because the fee for dropping beneath the minimum donut balance (average daily balance of 20 donuts) must be rounded to the nearest donut.

4.21.2006

Research on the Cutting-Edge

At first I was going to snark about the Brits coming up with yet another mind-blowing scientific discovery (since this article is posted on the BBC website), but it turns out that it's the Belgians this time. Seriously, how much money did they need to spend on an experiment to determine that, yes, straight men get distracted by scantily-clad women?

4.17.2006

Update

I haven't been writing much of late. I'm sure you noticed. I apologize, but it wasn't my fault: the sun was in my eyes. No, really, the stop sign wasn't visible! Er... it was the one-armed man!

We're fast approaching the wedding. It'll be nice to get that wrapped up. I'm looking forward to it. Still have some stuff to take care of; there's centerpieces (which Mom and Dad are working on), the cake (still on me, though I now have a good idea on how to get that done), and a few other little things. Everything will get done, I'm certain. Just could do with having it done and gone.

I've been reading quite a bit, up until this last week. Should go to the library or the bookstore or something.

4.10.2006

A Newspaper Headline only an Editor Could Love:

Urinals Backed Up by Conservationists

(saw it in a hallway on campus)

Some Things That I Enjoyed Very Much as a Child Yet Don't Seem to Enjoy so Much These Days or Maybe Just Don't do Very Often

  • Riding BMX-style bicycle
  • Jumping things on said bicycle
  • Throwing dirt clods
  • Baseball
  • Ghost in the graveyard (silly hybrid between tag and hide-and-go-seek)
  • Reading dictionary
  • Taunting Matt

Partial list of things that make me glad I abandoned vegetarianism

  • Double-doubles, animal style, from In-N-Out Burger. We had 'em for lunch yesterday, and I'm drooling at the memory.
  • Lamb. I am so going to hell for it, but adorable baby sheep are ridiculously delicious.
  • Cornish game hens, perfectly prepared. Scrumptious beyond measure.
  • The combined thrills of trying new foods and enjoying limitless menus.

4.07.2006

Shopping Lists

Would be funny if they were composed at a Ouija Board.

In Which Our Intrepid Hero has Transcranial Magnetic Stimulation

Once again, I have put my body to the test. Opened myself to prods and insistent questions. Sacrificed so that the sum of knowledge could grow. Yes, that's right, I was a paid subject for a human experiment.

This experiment was not terribly unpleasant. It was all a matter of sitting still while the experimenter discharged big capacitor banks through (insulated) wire coils he pressed up against the back of my head. No biggie. Turns out that when you discharge the capacitors, a great big current pulse flows through the coils. When that happens, there's a big pulse of magnetic field along (most particularly) the axis of coils. Further, magnetic pulse tends to interact with your brain in interesting ways.

A great deal of literature indicates that this practice is quite safe; people've been doing these experiments for at least 15 years and there's no indication that it has any malinfluence on the subjects.

Anyway, the magnetic field can stimulate the brain in nifty ways. In this case, he aligned the coils so the magnetic field would interact with the primary visual cortex. As a result, when the caps (capacitors) were discharged, the pulse of magnetic field would make me see this crazy spot just right of the center of my field of vision.

Apparently the idea is to flash some picture up on a screen and then, an instant later, stimulate the cortex and determine how the picture persists in the brain. Pretty swell stuff. I'm going to do it again next week for an hour; we'll see if there are more cool stories of bizarre field-induced hallucinations.

4.05.2006

Job Interview Stuff

Here is a list of odd statements made/heard at job interviews or in resumes. A few of my faves:

  • "I have an excellent track record, although I am not a horse."
  • "Personal interests: donating blood. Fourteen gallons so far."
  • "Received a plague for Salesperson of the Year."
  • "I know who is responsible for most of my troubles."

Minimum Differentiation?

Has anyone else noticed that the redesigned web presence for CNN, the Washington Post, and the New York Times all look suspiciously similar?

4.01.2006

The Minimalist to the Rescue

We tried a new recipe from The Minimalist, author of the most useful cookbook ever (How to Cook Everything: Simple Recipes for Great Food).

Here's the recipe:
  • Take 2lbs pork shoulder, cut into 1-2" chunks. Sear the meat and then put it aside (hell, retain the pan; you'll be making a sauce later)
  • You'll need 1lb of carrots (baby or chunked)
  • 2 cups fruity red wine (beaujolais or pinot noir, for example) (substitute 1/2 cup good vinegar and make up the volume with water)
  • 1 cup of nice stock
  • 10 or so cloves garlic, peeled
  • 2 tbsp butter (hmm, sinful)
  • a bit of flour (a few tablespoonfuls)
  • Egg noodles, about 1 lb
  • Combine the meat, stock, wine, carrots and garlic in a large pan (you'll need a big one, as this is a bit of a stew).
  • Bring to a boil, then simmer for about an hour (with the cover on the pot).
  • Strain out the solids, depositing the liquid into the pan you saved (the one with the tasty meat-searing-bits).
  • Reduce the liquid with high heat to about 1 and a half cups, scraping the bottom of the pan to release then good pork stuff.
  • Add the butter and lower heat to, well, low.
  • Add the flour, stir in carefully until smooth.
  • Salt and pepper to taste.
  • Cook noodles al dente, strain.
  • Combine everything, eat.
  • Thank me, Mark Bittman.