LSSTDESC / tomo_challenge

2020 Tomographic binning challenge
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FOM Behaviour #29

Open cdebom opened 4 years ago

cdebom commented 4 years ago

Dear @joezuntz and @EiffL. We found out that the resulting FOM_3x2 can be very different in multiple trainings.

For instance, if we use the RF example w/ 5% for training (100 times - 5 bins) we have found in the validation

image

Thus, one can find 10^4 as well as 6*10^4 using the same algorithm.

while the SNR_3x2 have variations lowers than 0.6 :

`image

If, instead of using RF we add the same the redshifts in the correct bin for the validation sample we find (5 bins) FOM_3x2 lower than 3x10^4, depending upon some selection. Thus we are getting Higher values than using the truth table.

Does this make sense for you?

pwhatfield commented 4 years ago

tomo_4 I have found a similar issue when varying parameters that describe the training smoothly, see figure, the FOM values jump around a fair bit...

dkirkby commented 4 years ago

Are you using jax-cosmo option to calculate the FoM? It should have better numerical stability.

pwhatfield commented 4 years ago

Er probably not sorry; does tc.compute_scores just need jax-cosmo=True or something?

EiffL commented 4 years ago

yes, essentially :-) @cdebom were you using the jax-cosmo version of the metrics? Because they should be more stable

cdebom commented 4 years ago

Yes, it seems that this was the issue. We are using jax-cosmo now. Thanks