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This turns out to be wrong; for a 6-member programming team, that probability is about 2⁻²⁴⁵, which is about 2⁸⁵·³ times less likely than an accidental 160-bit SHA-1 collision: http://canonical.org/~kragen/sw/dev3/rpn-edit#3_8_0_1_0_0_0_...

Aside from being bullshit, it's also irrelevant, since we're discussing a collision being generated on purpose, not by accident.



Just to nitpick, I don't think that formula is valid. We're primarily interested in "unrelated" wolf attacks, but it counts the total fatalities, not the total number of fatal incidents. If we count each fatal attack as only one incident, regardless of the casualties, we get 2^-258 instead.

But of course we also need to take into account where the 6-member team lives. If they all live in West Bengal, India, the consideration is much different than if our developers live in Atlanta. Atlanta doesn't have any wild wolves. There is a Wolf's guenon in the zoo, but that probably doesn't count as a risk because they mostly eat small animals and also are monkeys.


This is why I always get mad when people say something like "you are more likely to be struck by lightning than eaten by a shark!".... we'll, that REALLY depends on where you are.


> that REALLY depends on where you are

There's only 10 fatal shark attacks per year. What's your calculation for the sharkiest area to live? It has to be something like 100+ times sharkier than average for your claim to be true. And keep in mind that half the US population can easily day trip to the ocean.

Edit: Actually, that's using a number of 2000 lightning fatalities which might be 10x too low. And lightning injuries are another 10x higher than that. So you'd need somewhere that shark attacks are a thousand or ten thousand times more likely than average. That's also without interpreting "eaten" literally...


You focused on the shark side and not on the lightning side. You will never get struck by lightning in a city, so there the probability is 0. Similarly if you go out swimming in the ocean on a sunny day the probability of getting struck by lightning is also 0, but the probability of getting eaten by a shark is not 0.


You're going too granular. This is about populations that live in certain areas, not specific people on specific days. "depends on where you are" when talking about an over-time risk ratio. The goal isn't to find some dude with weird habits.

And while a population that mostly stays inside a city has a reduced lightning chance, it also has a reduced shark chance. I don't think that's anywhere near the point of equalizing the rate.

If you have an idea for a factor that dramatically reduces lightning risk but doesn't reduce shark risk much, I'm interested.


0 is not a probability; trying to use it as one leads to division-by-zero errors.


How do you represent the probability of an impossible thing, then?


You could always be wrong about it being impossible. People do make mistakes sometimes.


It also depends on what you are doing. If you are spear fishing in shark filled waters, you have a much higher chance of being bitten by a shark.

And if I live in a place where there is very rarely lightning, that chance gets really low as well.


> If you are spear fishing in shark filled waters

Like I said in my other comment, it's not about finding one specific guy. Picking a place where people live is a reasonable starting point for making a rebuttal to a general statement like that. I don't think pointing at Fisherman Sam is.

> And if I live in a place where there is very rarely lightning, that chance gets really low as well.

How low can that number go? The numbers I picked made consideration for some amount of variation in lightning. Does lightning have a huge variance?

It's important to have real numbers when you're making the claim that there are places where the lightning:shark ratio is multiple orders of magnitude lower than the average. That's not a claim you can justify by merely pointing out that the risks will vary by location.


There was an organization devoted to reintroducing wolves to the northeastern US, but I don't believe they found it politically feasible.

However, I have seen (and photographed) something I called a coyote, but others insisted was a wolf.

It has been asserted that coyotes tend to evolve to resemble wolves, when there are none in an ecosystem.


Wolves are slowly coming back, they were recently taken off the endangered species list in Idaho, Wyoming, and Montana.[1]

[1] https://www.nps.gov/yell/learn/nature/wolves.htm


For whatever reason, American wolves attack people much, much less frequently than Eurasian wolves.


That's a good point! I didn't think about either of those issues. The second one raises the average team's chances of such a spate of unrelated attacks significantly, if anything related to this formula could be said to be significant, because the increase in risk to teams in West Bengal and Ukraine is enormously larger than the decrease in risk to teams in Atlanta.


i laughed so hard i cried, thank you for this

(to everyone involved)


Plot twist: two developers of your remote team live in Rome and have been raised by a female wolf. How to account for that?


This is problematic because it must be 2774 years ago, when wolve attacks were substantially more common. I'm also not thrilled that a good chunk of my dev team lives near the Lupercal. The one good piece of news is that at least one of my headcount is fated to die by the hand of man, which might bring the odds of simultaneous wolf attack deaths down to zero unless he quits beforehand.


I concur.


> Aside from being bullshit, it's also irrelevant, since we're discussing a collision being generated on purpose, not by accident.

I think you just pointed out the error in your own reasoning. This is defending against a deliberate attack. Therefore, your proper odds would be that your programming team is deliberately set upon by 6 different wolves. So, have they offended people who have access to 6 wolves, and the time and inclination to train them (or hire others to) in an effort to pull off a murder spree?

Edit: Actually, the hash attack already assumes motivation and skill. So, I don't know what the odds would have to be computed. That at least one programmer on your team could fight off a trained attack wolf (to whatever level of "training" is the current state of the art for attack wolves)?




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