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Re: (meteorobs) Taurids vs. Leonids
Mike,
> It is POSSIBLE that due to statistical fluctuation, my 2nd period
> count was elevated by +4.8 and simultaneously my 3rd period
> count was low by -4.1, yielding a crosover as you say. However it
> is EQUALLY POSSIBLE my 2nd period was low by -4.8 and my
> 3rd period was high by +4.1, yielding a rate of 17.6 and 1.7 for
> periods 2 vs. 3 ! So isn't it most PROBABLE the actual mean value
> observed represents the truth? Of course, due to the small
> statistics and crossover at one limit of 65% confidence, any
> conclusion from these results are weak.
they are not weak, but not conclusive at all! That's the point Rainer
tries to make.
Let's have a look at the following example: There are 5 observers watching
the sky independently at the same time. They all observe the same average
sporadic rate of, say, 10. Then you would not expect that every observer
will have 10 SPOs in every intervall. In fact, there will be statistical
fluctuations: One observer may have almost constant rates, the next one
may have enhanced rates in the beginning, and another one in the end.
This is simply what we expect from Poisson distribution of random events.
If now one of these observers claims that he observes increasing/decreasing
activity from his individual counts alone it's obviously not conclusive.
By chance he was the one with the observed trend, not the one with
constant rates.
If an observation has no statistical significance, then you should always
stick to the most probable explanation. In this case that's a more or less
constant sporadic rate with statistical fluctuations. All you can do is to
collect data from more observers, improve statistics, decrease the error
bars and check whether you activity increase/decrease still holds.
Cheers,
Sirko
--
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