How to calculate the upperbound shown in Fig-1(c)

[tonysy]

Hi,
I have a question about how to calculate the map upperbound.
How to determine the classification score for each proposal in the RCNN stage and applied the score for the NMS(in RCNN)

Thanks for your work and hope to get your response.

To verify this, for the proposals generated by RPN [36], we assign their
ground truth class labels to the second stage as its classification results. Then
we evaluate the AP.