This is a known bug that is still being solved: MarginalApprox doesn't allow non-constant covariance parameters or inducing point locations in v4 · Issue #5922 · pymc-devs/pymc · GitHub
CC @bwengals
This is a known bug that is still being solved: MarginalApprox doesn't allow non-constant covariance parameters or inducing point locations in v4 · Issue #5922 · pymc-devs/pymc · GitHub
CC @bwengals