The model cannot converge when training

[dodgaga]

Hi,

I just followed the instruction to train the SSD model, but the loss can't fall.

At the beginning, the base_lr= 0.001 but the loss=nan Then, I set a lower base_lr = 0.0001 , the loss drops from 40+ to ~10 ,and don't have any change. Next, I kill the training and set the base_lr=0.001 and resume to train, the loss = nan again. So, maybe the 0.01 is too big for the model, I lower learning rate which base_lr= 0.0004, but the loss is aways ~8.

how much the loss in the SSD model will finally be? and can you give me some advice to training the data?

[yuantailing]

I find logs and plot the loss. Here are

1. loss of iteration 0 - 120,000, and

2. loss of iteration 1,000 - 120,000.

[yuantailing]

Since there are ~320,000 subimages, about 320,000 / 14 = 23,000 iterations is 1 epoch. Don't pray loss falling down before 1 epoch.

base_lr = 0.001 is OK for batch_size = 14. It it do not converge, I think you may set base_lr = 0.0004 - 0.0008 and no need to modify it.

[dodgaga]

Thanks! u are right. After 40,000 interations, the loss tends to be 4. The final loss in your log is ~3, Don't you think it is a bit too high?

[yuantailing]

Maybe too high, maybe not comparable. Final AP should be close to YOLOv2.