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Comment by feral | Hacker News Reader

But it does, if you assume constant speed. (I almost wrote that in my comment but decided it was too obviously implied to mention.)

So if we assume that's implicit in my example, how does the Wikipedia page on the contrapositive help now? (It doesn't, as my argument isn't relying on any property of it.)

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So are you saying Pareto distributions follow linear relationships? Are you sure about that?

I would read up on the topic if I were you. Statistics can be unintuitive sometimes, and basing your argument on supposition can be unreliable. I'm not sure about the correct answer here, but most folks get e.g. the Monty Hall problem incorrect if they rely on their intuition.

For a product at T = 0, why would it be optimal to assume its lifespan would be T = 0 as well, rather than the average age of all products?

>saying Pareto distributions follow linear relationships

No; not sure where you got that from.

>For a product at T = 0, why would it be optimal to assume its lifespan would be T = 0 as well, rather than the average age of all products?

I'm not saying it would be. (The original blog might, but that's irrelevant to my posts here.)

If you knew the average lifespan of all products, that would be your best estimate of the lifespan of a new product. (You can't use average age naively without thinking about right censoring.)

If the average lifespan of a product was short, then the average lifespan of a new product would be short. As the product aged, it's expected lifespan would increase.

I.e. the longer something has been around the longer it will be around, or, equivalently, the shorter it has been around the shorter it will be around (both obviously taking about expected times.) Make sense now?

> I would read up on the topic if I were you. Statistics can be unintuitive sometimes, and basing your argument on supposition can be unreliable. I'm not sure about the correct answer here, but most folks get e.g. the Monty Hall problem incorrect if they rely on their intuition.

But this is a stupid-obvious problem. The Lindy effect is easy to write out in formalisms:

    age(x) > age(y) ⟶ life_expectancy(x) > life_expectancy(y)

Here's the claim that Etheryte says is the opposite of that:

    age(x) < age(y) ⟶ life_expectancy(x) < life_expectancy(y)

It is hopefully obvious that these two claims are identical, not opposites. But if it isn't, consider that we can rewrite the first one like so:

    age(y) < age(x) ⟶ life_expectancy(y) < life_expectancy(x)

Statistics aren't relevant to the question in any way; it doesn't matter whether they can be unintuitive sometimes.

There is no reason to assume content speed. Initial statement does not assume constant speed.

I mean, the 'initial statement' we're talking about here was my hypothetical example, right?; just pretend I decided not to leave out "assuming constant speed" after I first wrote it, and we're good? Unless you are referring to a different statement in which case we're all mixed up and have exceeded the carrying capacity of HN threads :)

You have to take a long time to walk a long distance. Regardless of whether your speed is constant.

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