Tutorial for Kaggle NDSB-1

This is an MXNet example for Kaggle Nation Data Science Bowl 1. Test/train image data and sample submission have to be downloaded from https://www.kaggle.com/c/datasciencebowl/data. into a “data” folder. Uncompress train.zip and test.zip folders.

Step 1: Generate image list

• Prepare original data, in layout like

--gen_img_list.py
--data/
    |
    |--train/
    |   |
    |   |--acantharia_protist/...
    |   |--.../
    |--test/...

• Run command python gen_img_list.py --train to generate a the train image list
• If no extra arguments are passed it will generate the list of the train set (train.lst) and it will also automatically split the list into a train and validation set (tr.lst and va.lst in the /data directory). There is an option to use using stratified sampling and/or to give the percentage of set that is assigned to validation.
• Run command python gen_img_list.py --image-folder=data/test/ --out-file=test.lst to generate a test image list

Step 2: Generate Image Record (new shape with short edge = 48)

• mkdir data48
• Run command ../../bin/im2rec data/tr.lst ./ data48/tr.rec resize=48 to generate training data record file
• Run command ../../bin/im2rec data/va.lst ./ data48/va.rec resize=48 to generate validation data record file
• Run command ../../bin/im2rec data/test.lst ./ data48/test.rec resize=48 to generate validation data record file

Step 3: Train Model

• The network structure is defined in file symbol_dsb.py
• We will use find_mxnet.py and train_model.py from the image-classification example folder. Generate symbolic links to those files ln -s ../image-classification/find_mxnet.py . and ln -s ../image-classification/train_model.py .
• mkdir models , if you want to save the models in that folder.
• Run python train_dsb.py to train the model, look to the help of that file to change the parameters. (See Step 4 if you want to make training curve plot)
• Sample settings would get you

2016-01-16 22:03:48,269 Node[0] Epoch[49] Train-accuracy=0.664038 2016-01-16 22:03:48,269 Node[0] Epoch[49] Time cost=25.107 2016-01-16 22:03:51,977 Node[0] Epoch[49] Validation-accuracy=0.647807 2016-01-16 22:03:51,999 Node[0] Saved checkpoint to “./models/sample_net-0-0050.params”

Step 4: Plot train / validation curves.

• If you want to make a training/validation vs epoch plot you should save the log of the model fit to a logfile. For example, train the model with: python train_dsb.py --log-file "log_tr_va" --log-dir "."
• Make the plot: python training_curves.py

Step 5: Test predictions

• We will use epoch no. 50 to make predictions on the test set.
• Run python test_dsb.py to make predictions on the test.rec, look to the help of that file to change the parameters
• This will call submission_dsb.py function to generate the a csv file to be submitted to kaggle leaderboard, you should get around position 325.