MFD poor fitting

[79seismo]

Hi, I am trying to fit MFD parameters on a well established national catalogue using the Wiechert() method but the fitting is poor. Here is my code snippet:

`recurrence_estimator = Weichert()
recurrence_config = {'magnitude_interval': 0.1}

bval, sigma_b, aval, sigma_a = recurrence_estimator.calculate(catalogue,
config=recurrence_config,
completeness=None)`

The resulting a and b values are as follows:
a = 359.323 (+/- 3.771), b = 0.406 (+/-0.005)

Whereas the expected a-value is around 4.0 - 5.0 and the b value is around 1.0 - tested with various independent methods + published.

Here is the data that demonstrates that the MFD is well behaved.

Can someone please explain why the Weichert() method behaves in this way?

Thank you!

[micheles]

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