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diku-dk / bfast

GPU Implementation for BFAST
GNU General Public License v3.0
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What does the means represent? #8

Closed Carolina710 closed 3 years ago

Carolina710 commented 3 years ago

Hello,

I read this article https://arxiv.org/pdf/1807.01751.pdf but I don't have entirely sure what are the values returned in the means array. Corresponds to the magnitude?

You can use the subset_1 data: https://drive.google.com/drive/folders/1MkvA-MSvZCu_8WHkQ4p3R8Z0Qv_Vq-JC?usp=sharing And this gist: https://gist.github.com/Carolina710/330b473478dd59188edaaa6a3fd76bb6

My means values are always negative, in Python version is like Max:0, Min:-3.1542912 and OpenCL Max:0, Min:-47.075047

What results could I rely on more accurately? Python or OpenCL?

Thank you all!

mortvest commented 3 years ago

Means is NOT the magnitude, means is an array containing the mean values of the individual MOSUM processes, while the magnitudes (according to the R implementation) is the median of the difference between the data and the model prediction in the monitoring period.

Magnitudes are currently not supported, but are going to be added soon.

Furthermore, there is a bug in the OpenCL version, so if you wish to use the means (not magnitudes) you can rely more accurately on the Python version. This bug is also getting fixed soon.

I hope this helps

Carolina710 commented 3 years ago

Thank you, it was very enlightening!