Picky, Picky, Picky

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Schneier on Security: Lockpicking and the Internet

Earlier this year, Schlage launched a series of locks that can be opened either by a key, a four-digit code, or the Internet. That’s right: The lock is online. You can send the lock SMS messages or talk to it via a Website, and the lock can send you messages when someone opens it — or even when someone tries to open it and fails.

Sounds nifty, but putting a lock on the Internet opens up a whole new set of problems, none of which we fully understand. Even worse: Security is only as strong as the weakest link. Schlage’s system combines the inherent “pickability” of a physical lock, the new vulnerabilities of electronic keypads, and the hacking risk of online. For most applications, that’s simply too much risk.

Here's to You, Mrs. Robinson

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Deet, de de de deet deet, de de deet deet de de deet.

The DEET alarmism story you didn’t see in the newspaper

[F]or people who use DEET in the recommended manner, there are simply no problems, and the new study does nothing to change that, Lorin said. Indeed, after a review of published and unpublished literature of DEET’s toxicity in 2003, the American Academy of Pediatrician raised the recommended level of DEET concentration in repellents used on children to 30 percent from 10 percent, and lowered the minimum age for use from 2 year to 2 months.

In other words, the body of scientific literature suggested DEET was considerably safer than previously believed.

On side note, I had a tough time finding anything with 25% DEET in it last summer; most of the “family” sprays were 7%. I happened across some of the tougher stuff this spring and snapped up two bottles. And I hardly ever hallucinate.

A Vegetable is only Deception

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The Fruit Is A Lie

A fruit — a ‘true fruit’ — is one where all tissues are derived from the plant ovary and this alone. This includes peas. Whereas strawberries, for example, also include some of the flesh from the peg that holds the ovary, disqualifying them from fruit status. The apple gets its carpels involved as well as the ovary, leading to a kinky pome. ‘True berries’ are also ‘true fruits’, but not the other way round. Grapes, currants (red and black), elder- and gooseberries are all proper upstanding berries which will not deceive you or smuggle themselves into your house in pies before stealing your silver while you sleep.

So why call it a fruit when it isn’t? To most of us, knowing the particulars isn’t all that important in the grand scheme of things, though this sort of knowledge is possibly useful for the aspiring lawyer-type child, looking for a loophole to not eat their tomatoes and bell peppers after being admonished to eat their vegetables. We’re after the first-order approximation here, not the more detailed solution. I don’t particularly care if it’s not really a fruit, but it’s actually a fruit wrapped inside a mystery, with little enigmas on the outside — I want to throw it into a category and forget it. Is it a fruit or a vegetable? “False dichotomy” is not an acceptable answer for a non-biologist (or even for a pedant who’s off-duty)

The Vast Wasteland, Even Bigger

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My TV died last night, right in the middle of The Daily Show (the 8:00 repeat). One minute Jon Stewart was there, the next, he wasn’t. I’m not lamenting the loss of the TV all that much — it was a mediocre set I got 5 years ago (I had to check my receipts; it seemed more recent, but it was June of ’04) when my last set died.

The one thing I have demanded in each TV is that it be bigger than the previous one. The 26″ set I got after I graduated college gave way to a 29″ set purchased in Canada during my years of hiding, to this recently-deceased 32″ set, a cheap transitional CRT TV I got because I could not afford an HD set; plasmas were too expensive and über-large LCDs were in their infancy. Now, I am ready to take the 40″ HD plunge. Right in time for football season.

Mistakes? What Were the Odds of That?

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What’s luck got to do with it? The maths of gambling

He wasn’t on a lucky streak, he was using his knowledge of mathematics to understand, and beat, the odds.

“Beat the odds” isn’t quite as bad as “defies the laws of physics,” I think. But exploiting knowledge of the odds to win isn’t beating the odds. Beating the odds is winning when you shouldn’t — drawing to an inside straight and hitting it to win a hand is beating the odds. Exploiting the situation to make the odds go in your favor — making it so you should win more than you lose — is not.

A spin of the roulette wheel is just like the toss of a coin. Each spin is independent, with a 50:50 chance of the ball landing on black or red.

Well, no. A roulette wheel has 37 or 38 slots, depending on where you play, with 36 of them being black or red. The others are green — 0 and 00 (Europe has one, the US has both. Sort of.) That’s why the house makes profit offering “even money” on black or red bets on a US wheel; the probability of winning is slightly less than 50%. (They also make money on the single-number payouts, at 35:1) All of the bets on a 00 roulette wheel have a house advantage of at least 5.26%; single-0 wheels have a smaller house advantage but there also seems to be a correlation with higher-stakes limits. The previous link also presents a section on debunking the “doubling down” method for roulette. Winning at roulette is truly “beating the odds” since the house always has an advantage.

So please don’t follow the advice here. But note this:

For what it is worth, the sum of all the numbers in roulette is 666.

Bang Bang!

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Built on Facts: Maxwell’s Equations come down upon your head.

#1
#2
#3
#4
#5

(Link 5 is premature at the time of this posting, but based on the syntax of the earlier posts. It should go “active” later today)

Update: Gah, Matt zigged. Link fixed.