About HPPB

[mufeili]

@rbharath @peastman I notice that the RMSE values I am getting for HPPB are more than 17. I guess we also need to take logarithm for this dataset.

[rbharath]

+1 for trying a logarithmic transform for this dataset.

[mufeili]

I think this should be a default option as I do not need to manually specify that for Delaney.