AAWSAP DIRD, An Introduction to the Statistical Drake Equation, March 2010

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This possibility of ADDING ANY NUMBER OF FACTORS IN THE DRAKE EQUATION (7)
was not envisaged, of course, by Frank Drake back in 1961, when "summarizing" the
evolution of life in the galaxy in SEVEN simple STEPS. But today, the number of factors
in the Drake equation should already be increased: for instance, there is no mention in
the original Drake equation of the possibility that asteroidal impacts might destroy the
life on Earth at any time, and this is because the demise of the dinosaurs at the K/T
impact had not been yet understood by scientists in 1961, and was so only in 1980!
In practice, the number of factors should INCREASE as much as necessary in order to
get better and better estimates of N as long as our scientific knowledge increases. This
is called the "Data Enrichment Principle" and believe should be the next important goal
in the study of the statistical Drake equation.
Finally, a numerical example explaining how the statistical Drake equation works in the
practice will be given in the next section.
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