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I misread the numbers in the original post. But what you say in your comment- well, that's not how it works. To assess the risk posed by a driver, you wouldn't follow them around, constantly logging the miles they drive, counting the deaths they cause and continuously updating the probability they will kill someone, at least not in the real world (in a simulation, maybe). Instead, what you'd do is wait for enough people to have driven some reasonably significant (and completely arbitrarily chosen) distance, then count the fatal accidents per person per that distance and thereby calculate the probability of causing an accident per person per that distance. That's a far more convenient way to gather statistics, not least because if you take 1000 people who have causd an accident while driving, they'll each have driven a different distance before the accident. So you might come up with a figure that says "Americans kill 1.18 people every million miles driven" (it's something like that, actually, if memory serves). Given that sort of metric, you can't then use it for comparison with the performance of someone who has only driven, say, 1000 miles. Because if you did, you would be comparing apples and oranges: 1 accident per 1000 miles is not on the same scale as ~1 accident per million miles. There's still another 999k miles to go before you're in the same ballpark. And on that scale, no, you can't know whether an accident in the first 1000 miles will be followed by another in the next 1000 miles. Your expectation is set for 1 million miles. It's a question of granularity of the metric. |
But think about this, if I killed a person in my first 10 km of driving, what is the chance that will kill 0 after the next 999990, would you bet that I will kill 0 or 1 , more then 10?