just a note to be brought up with Melissa, to commit to memory until she's back from Michigan:
Basis: Cannon trained with 5 labels, with ages from Kepler; with the Cannon, we get "age" recovered as a parameter with +-2 Gyrs. BUT: to which extent is the age just a corollary of [a/Fe] and [Fe/H]?
[FromMarie's work, we KNOW that there's more information ...]
Plan to find out:
Application of the age label (as is) to the DR12 RC sample, yields <age>([Fe/H],[a/Fe]);
let's define D(age)_Kepler == age_Kepler - <age>([Fe/H],[a/Fe]) and
D(age)_Cannon == age_Cannon - <age>([Fe/H],[a/Fe])
and plot
D(age)_Kepler vs D(age)_Cannon (as opposed to age_Kepler vs age_Cannon),
i.e. we look at a version of the age vs age plot, compressed around the mean age at a given abundance.
If the Cannon teaches us nothing new about ages beyond that which could be known from
[Fe/H] and [a/Fe], we should get a scatter plot.
HWR's conjecture: the extent along the 1-to-1 line will be ~2 times the scatter..; so, there is more in the spectra...
