alt Hacker NewsThis is neat, but I don't think it's actually drawing the year from the correct probability distribution - "a random birth is far more likely to fall near the present" is correct, but in 5 "random" choices, only one was from anywhere near modern day.
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I think it's working as intended. The year is simply a randomly chosen year not related to the density of births in that year. It would be a boring tool if it actually chose "random year based on random birth" because almost every choice would be from 1900 onward...
There are more statistical issues. I drew a person from 1984, living in Germany and recalculated their life several times. In almost all cases, their mother died while they were in their thirties, often both parents. This is simply far from reality.
> "a random birth is far more likely to fall near the present" is correct,
If the selection is from the population at random (as the UI indicates), but it specifically says it's based on a random year (during which humans were present) first as a filter. It's much more likely to select far from the population explosion.
The x-axis being log scale by default visually exadurates the effect if you are thinking about it in terms of area under the curve. This confused me also.
I guess you are right, but it makes it more interesting if the picks are not almost all from the recent past. On the other hand, I would also guess that spreading the picks evenly across the time range might result in many being from times with little data to differentiate them.
That's sort of boring though, we generally know what it's like to live near the modern day already.
Yes, this is exactly what I expected (showing the anthropic principle in action), so I am disappointed they are not sampling correctly.
How near is near? With ~100 billion people having ever lived, the odds of a randomly selected life falling within the past couple of centuries are not all that high.
I did a statistical analysis and you are correct. The issue seems to be that crude birth rates from around 500CE and earlier are overestimated significantly. The bad source seems to be Kaneda & Haub, "How Many People Have Ever Lived on Earth?", where they assume a flat crude birth rate of 80 for all BCE dates. The probability distribution is just a function of pop and CBR, so it results in significantly decreasing modern birth probabilities.