OHEM and focal loss, which is better?

[chengyu0910]

Hi, is the focal loss works in SSD? How much improvement is reached in VOC2007 evaluation when SSD is trained with focal loss? I want to know whether the focal loss performs better than OHEM(used in original SSD). Thank you!

[gakkiri]

For me, focal loss didn't work well in SSD.

[zhaohao0404]

I have a question : why exclude the number of negative sample in multi_box_loss? (Line 68 69)