boax.acquisitions.log_probability_of_improvement

boax.acquisitions.log_probability_of_improvement#

boax.acquisitions.log_probability_of_improvement(bounds, improvement_factor=1.0, num_raw_samples=512, num_restarts=10)#

The Log Probability of Improvement acquisition function.

Logarithm of the probability of improvement over the best function value observed so far.

logPI(x) = log(P(y >= best)), y ~ f(x)

Example

>>> acqf = log_probability_of_improvement(0.2, model)
>>> log_poi = acqf(index_points)
Parameters:
  • best – The best function value observed so far.

  • model – The surrogate model.

Return type:

Acquisition

Returns:

The corresponding Acquisition.