Estimates? Here some quotes from the paper on those “estimates”:
“Also Lc, the average longevity of a communicative civilization, cannot be inducted from its short history on Earth and could be anywhere between a few hundred years and billions of years.”
“Bayesian analysis demonstrates that as long as Earth remains the only known planet with biotic life, any value could be assigned to Fb”
You tell me how valuable these estimates are, in view of their precision....
We may not have good measures for estimating Fb or Lb let alone Lc, but the Kepler mission gives us a pretty good estimate of Rb. You should update your estimate of the closeness of a biotic planet depending on whether your Rb prior was higher or lower than the result.
That is true. However, if “any value could be assigned to Fb”, then any value can be made to come out of the Drake equation, except for an upper bound. Updating on Rb can shift around that upper bound, but it tells you nothing about the really small values that decide whether we are alone in the universe or not.
Estimates? Here some quotes from the paper on those “estimates”:
“Also Lc, the average longevity of a communicative civilization, cannot be inducted from its short history on Earth and could be anywhere between a few hundred years and billions of years.”
“Bayesian analysis demonstrates that as long as Earth remains the only known planet with biotic life, any value could be assigned to Fb”
You tell me how valuable these estimates are, in view of their precision....
We may not have good measures for estimating Fb or Lb let alone Lc, but the Kepler mission gives us a pretty good estimate of Rb. You should update your estimate of the closeness of a biotic planet depending on whether your Rb prior was higher or lower than the result.
That is true. However, if “any value could be assigned to Fb”, then any value can be made to come out of the Drake equation, except for an upper bound. Updating on Rb can shift around that upper bound, but it tells you nothing about the really small values that decide whether we are alone in the universe or not.