Hi everyone,
I'm fitting data with the least-squares method in Athena and am not sure
what the error bars correspond to. What I mean, are these 95% confidence
limits, or is it some other statistical way for error analysis? If Athena
says the weight of one phase is 0.049 (0.003), what
On Thursday 02 October 2008 18:06:19 Matt Newville wrote:
Does it? I thought it used data_uncertainty=1 unless the uncertainty
was explicitly specified. Does Athena use a value determined from the
sigma when merging data, or is something? Should I read the Users
Guide more closely?
Athena uses Ifeffit's minimize function. As you say, the data
uncertainty is set to one, so the diagonals of the covarience matrix
will be orders of magnitude too small. My understanding is that
Ifeffit rescales the error bars on the variable parameters in the same
manner as the feffit
