If my counting units had been years then you'd be right to imply my degree of error was wildly off the mark, but they weren't. If the two events had occurred within the same hour instead of within the same day, my calculation would have been an even greater "far cry" from the time base of years but it is still reasonable to base the calculation on counting units derived from the distance in time between the events. What if they had occurred within the same minute? The same second?
In fact, the two events occurred within 16 hours of each other, not 24 hours. Otherwise, thanks for pursuing a less naive calculation but you failed to show your work. "Taylor expansion" doesn't cut it. Please update it for 16 hours rather than 24 hours and show your work. By work I mean something more specific than "taylor expasion" which is about as vague as you can get. On Thu, Feb 28, 2013 at 2:36 AM, George Paulson <[email protected] > wrote: > 271.8*16,000 comes out to 4,348,800 days. 4,348,800/365 comes out to > 11,915 years. > > So like I said we can expect an event like this roughly every 10,000 years > or so. > > That's a far cry from the one in one billion odds or the one in one > million odds after discounting by a factor of a thousand, isn't it? > > > ------------------------------ > Date: Thu, 28 Feb 2013 01:04:34 -0600 > Subject: Re: [Vo]:Russian meteor coincidence odds > From: [email protected] > To: [email protected] > > > You quote me incorrectly. My actual words were "less than one in a > million". I stated so because mine was a "naive calculation" that came up > with 1/1332250000 to which I then applied a "discount by a factor of a > thousand" precisely to address such arguments as yours. > > To normalize your calculation properly you have to multiply 271.8*16,000. > > Now, can you do that arithmetic for us to complete your "critique"? > > > On Wed, Feb 27, 2013 at 11:13 PM, George Paulson < > [email protected]> wrote: > > In an earlier message, James Bowery claimed that the odds of the Russian > meteor and asteroid DA14 passing Earth on the same day were "one in a > billion": > > http://www.mail-archive.com/[email protected]/msg76844.html > > "The odds of this coincidence are literally far less than one in a > million. The naive calculation is based on two like celestial events that > independently occur once in a hundred years occurring on the same day: > > 1/(365*100)^2 > = 1/1332250000 > > Note: that is one in a billion. Discount by a factor of a thousand for > whatever your argument is and you are still one in a million. > > This is not a coincidence." > > This is incorrect. It is more like the birthday problem, where we're looking > for the number of "years" that pass until two wandering asteroids have the > same "birthday". A birthday here is when they fly by the Earth. > > > We can expect the fly by of a DA14 type object every 40 years. If we > also assume that something like the Russian meteor passes by every 40 years, > this gives us a 16,000 day "year", and with a Taylor expansion you get a > > > 99% probability of there being a coincident "birthday" after 271.8 "years", > or roughly 10,000 of our years. > > So we can expect an event like this once every 10,000 years. > > >
