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News - Free Day Documentary Part… | about 2 months ago

Dude, your numbers are misleading, and I don’t know if I have the patience tonight to clarify sufficiently. Most nights I would.

Assuming your numbers are right (sorry, I don’t remember) your post hoc chance of winning on your FIRST captcha was p=1/3250 (IIRC, at least one guy on IRC reported doing so — but most who did would be unlikely to stick around, except for giggles) At 10 captchas/min, you’d have a 50% chance of winning after 2252.38 tries (about 3 hrs 45 minutes) or a 2/3 chance of winning in 6 hrs, assuming my watch calculator carries a sufficient number of digits of internal precision (12-14 IIRC) and I typed the digits correctly. It’s a Poisson distribution or 1-p, because the right way to calculate it is by iteratively multiplying the odds of losing (3249/3250) not the chances of winning. The # of trials for 50% is e^{ln(0.5)/ln(1-p)} [or 10^/Log, if you prefer that to e^/ln] The chances of NOT winning in 3600 tries (6 hrs @ 10/min) are e^{3600* ln(1-p)} If you don’t get why, I hope someone will explain. It just won’t be me. Not tonight. Sorry. Also I may have it wrong (hardly unheard of), but that number accords with a lifetime of experience, and my Free Day observations. I ran the math in Sparkfun’s IRC chat when I was in a better frame of mind, and a lot of folks got it.

I realize that doesn’t dull your pain, and I sympathize

Also: kudos to Sparkfun on your site’s excellent automatic superscripting of exponents. None of the servers I run handle that as well without explicit superscript tags — but dammit, Jim, I’ve been a physician, not a programmer, for decades.

Product WRL-10153 | about 3 months ago

Mine, purchased Mar 2011, weighed .70-.71 g fresh out of the bag

If you really need to, you should be able to shave a few .01s off that with a jewelers file

Product TOL-10951 | about 5 months ago

I don’t know if you are just interested in DIYing this, or if you want colors for your application, but it is also sold for craft use under the brand name Friendly Plastic in many vivid and/or metallic colors http://www.amaco.com/shop/product-775-friendly-plastic-assortments.html

News - According to Pete - July … | about 11 months ago

I know that it may seem tempting, but licking the Dry Erase board clean pretty much always produces this result. At best.

News - The Automatic Cat Faucet | last year

When I was a boy, we had simple $5 mechanical valves (a bit more money in those days than now, but hardly expensive, and you could get them cheaper on clearance) where a dog or cat could press a tongue/paw on a rod protruding from the faucet nozzle to displace a ball that allowed water to pass. A spring or water pressure shut it off when the animal quit drinking. Flooding was little concern because the animal would have to sit there and get drenched to flood the bathroom.
I’d trust those over any electronic gizmo any day, and they have decades of track record. I never heard a disaster story

News - Maker Faire, SparkFun Fli… | last year

Let’s see you “welcome your overlords” THIS, buster!

News - Maker Faire, SparkFun Fli… | last year

Well, childbirth works rather differently in my species, but we’re past the hard part now.

News - A Few New Classes | about a year ago

I did read The Adventures of Huckleberry Finn, but it was Tom Sawyer (in a different book) who tricked the other boys into doing his whitewashing. I don’t mean to be picky, I just thought you’d want to know, if you ever use that [useful] example again.

Product TOL-10326 | about a year ago

If I was an ordinary web surfer instead of a middle aged geek who has used creme brulee as an excuse to buy torches and other gadgets for 30 years (and only prepared it for the occasional valentines or birthday), this thread would make me suspect “creme brulee” was a euphemism for some sort of extreme kink.

News - Free Day Funds Expiring! | about a year ago

I’ve been trying to think of a good way to encourage the 40% who hadn’t spent their Free Day funds. I think I’ve found it: a free/reduced shipping weekend!
This would especially appeal to those who had smaller winnings, and would minimize upset to those who spent their funds immediately, because they could get equivalent savings by placing an order now (though every promotion by every company inevitably comes at the wrong time or isn’t appealing to all their customers, I’m sure SF doesn’t want to be flooded with gripes) It would also encourage people to make their wishlist purchases now, which is surely good for business.
You could justify it as [roughly] disbursing the ultimately unclaimed funds as free shipping. It wouldn’t be the exact amount, but between added sales revenue and the $10-20K that will undoubtedly remain unclaimed, you’d be in the ballpark.