If there is not a climate trend, we would expect this to happen with a .05 chance.
If they meant the latter, my confusion is resolved.
Fundamental truth: bayes theorem.
P(evidence | null hypothesis) = P(null hypothesis | evidence) * P (evidence) / P (null hypothesis)
The P-value test determines:
P(evidence | null hypothesis) = 0.5%
= there is a 0.5% chance of the observed evidence given the null hypothesis
The statement "We estimate that there is a 99.5 percent chance that the observed retreat did not happen in the absence of a climate trend."
translates to P(!null hypothesis | evidence) = 99.5%
By Bayes theorem:
P(!null hypothesis | evidence) = P(evidence | !null hypothesis) * P (!null hypothesis) / P (evidence)
We know almost none of these terms. The answer is not as simple as 99.5.
Fundamental truth: bayes theorem.
P(evidence | null hypothesis) = P(null hypothesis | evidence) * P (evidence) / P (null hypothesis)
The P-value test determines:
P(evidence | null hypothesis) = 0.5%
= there is a 0.5% chance of the observed evidence given the null hypothesis
The statement "We estimate that there is a 99.5 percent chance that the observed retreat did not happen in the absence of a climate trend."
translates to P(!null hypothesis | evidence) = 99.5%
By Bayes theorem:
P(!null hypothesis | evidence) = P(evidence | !null hypothesis) * P (!null hypothesis) / P (evidence)
We know almost none of these terms. The answer is not as simple as 99.5.