Jach's personal blog

(Largely containing a mind-dump to myselves: past, present, and future)
Current favorite quote: "Supposedly smart people are weirdly ignorant of Bayes' Rule." William B Vogt, 2010

Apple should bow to the court

Unlike most of the internet, I'm in favor of the Feds compelling Apple to "unlock" the terrorist's iPhone. This is because I'm a proponent of Order and because I'm familiar with the technical details.

On the side of Order, I find myself aligning with Trump. The federal government has given a US company an order, and the US company is fighting it. (Amusingly they weren't planning on doing so until another judge suggested it.) Generally speaking, when the entity in charge gives an order, the subordinates should follow it. This is the Way to keep good order and established hierarchies. There are precious few scenarios where it makes sense to rebel instead, and I don't think this is one of them.

On the side of the technical details: even if Apple does what the feds want, that doesn't necessarily help the feds. This is because all they want Apple to do is disable the wipe-device-after-n-passcode-attempts feature, and maybe to also delay any artificial time limits between attempts that aren't inherently due to the key derivation scheme. All this so that they can have an easier time brute-forcing the device. In theory. Yeah they can hire some kid to try 0000-9999 for super cheap, and if that fails inserting a device under the touchscreen to quickly try 000000-999999, but if the passcode is a lot longer, or text-based, then it can quickly become as difficult as brute-forcing "Zero reverberate business digital work most failure offset!" -- that is to say basically impossible. A strong passphrase is immune to Apple working with the feds or not, because Apple has already done the right thing by not storing the plaintext anywhere.

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Automated anonymous surveying

Jonathan Blow was recently quoted in media as saying: "...piracy rates for PC games are often 85-90 percent. That's true. If 10 percent of people who pirate games would buy the games, that would double profits. Double! That's insane. That's the difference between starving to death and being comfortable enough to make the next game." This bugged me for a few reasons, and this from someone who never pirates games.

First check: does the math make sense? (Skip to the last parenthetical, it sort of does.) If you sell your game for $10, and get 100 customers, you've made $1000. But if the piracy rate means that if you track the count of legit users and track the count of pirate users (assuming none overlap, I'll get to that) you should see around 85-90 pirate users per 100 legit users. In other words, another $850-$900 in missing sales. If just 10 percent of those 85-90, 8.5-9, we'll round to 9, bought the game, that would result in an increase in sales by $90, bringing the total to $1090. This is nowhere near "double" revenue, but can it be double profit? Maybe I'm misunderstanding what he means by his whole remark -- perhaps he means for his game in particular? But he hasn't made a profit yet, so that seems doubtful. The only way the statement could be true is if the game cost $910 to make. If that is true, then at 100 sales, you've made $90. And if 10% of the pirate users paid, you've made another $90, doubling your profits. But this doesn't hold for any further periods of time. If after the game has been around for a while, you have made 1000 sales total (and there are now 900 pirates), you have made $10,000 in total sales, and a total profit of $8,090. Now assume 10% of those pirates now pay, or 90 users, that would net you an additional $900 in profit. This is far short of double profit. So his statement makes no sense mathematically, at least to me. (Okay, let's try one more time... Let's suppose that a 90% piracy rate means that if there are 100 copies of a game out there, 90 of them are pirated, and only 10 of them are legit individual sales. Look at 1000 copies out there, only 100 legit, total sales is thus $1000, let's say the game cost $100 to make, so profit is $900. If 90/900 pirates bought, that's an extra $900, so double profit. As you increase the number of copies, or take the cost-to-create to $0, the limit is actually 1.9 though, not strictly double. I assume this is what was meant.)

Second check: you're ignoring the possibility that 10% of people who pirate games haven't also already bought your game, before or after pirating. If this possibility is true, and if we also assume the remark is true (in whatever way), then if you waved a magic wand to suddenly get rid of piracy, your profits could halve!

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