• Corpus ID: 118513268

The Log Log Prior for the Frequency of Extraterrestrial Intelligences

@article{Lacki2016TheLL,
  title={The Log Log Prior for the Frequency of Extraterrestrial Intelligences},
  author={Brian C. Lacki},
  journal={arXiv: Earth and Planetary Astrophysics},
  year={2016}
}
  • B. Lacki
  • Published 19 September 2016
  • Physics
  • arXiv: Earth and Planetary Astrophysics
It is unclear how frequently life and intelligence arise on planets. I consider a Bayesian prior for the probability P(ETI) that intelligence evolves at a suitable site, with weight distributed evenly over ln(1 - ln P(ETI)). This log log prior can handle a very wide range of P(ETI) values, from 1 to 10^(-10^122), while remaining responsive to evidence about extraterrestrial societies. It is motivated by our uncertainty in the number of conditions that must be fulfilled for intelligence to arise… 
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