GP overfitting data

[avivajpeyi]

Overfit GP EGs

TOI 103:

Notebook:
toi_103.ipynb.zip

TOI 1006

Some others

Note: appears to be performing ok(?) in some cases

[avivajpeyi]

TOI 178:

[avivajpeyi]

There was a mistake in the model 😑... a very silly mistake:

The original code

residual = y - lightcurve
gp = GaussianProcess(
    kernel, t=t, diag=yerr ** 2 + jitter_prior ** 2, mean=lightcurve
)
gp.marginal(name="obs", observed=y)

This makes the GP fit the raw relative flux data, and makes the GP mean->lc

Here we see that the GP is fitting the transit, and the transit model does not fit all the transit data.

Modified model

residual = y - lightcurve
gp = GaussianProcess(
    kernel, t=t, diag=yerr ** 2 + jitter_prior ** 2.0
)
gp.marginal(name="obs", observed=residual)

Making the GP fit the residual and removing the mean-->lc, we get the following:

This seems better -- Ill merge it in but should check in with Dan to see if it is correct.

[dfm]

That looks perfect! Good find.