Riiid! Answer Correctness Prediction solution

This is the 3rd place solution source code to Kaggle's Riiid! Answer Correctness Prediction competition. For a brief write-up and comments please check the discussion topic on Kaggle.

The solution will be presented at the 35th AAAI Conference on Artificial Intelligence (2021).

Steps to reproduce

Used hardware

• Threadripper 1950x + 256 GiB RAM + 6 x RTX 3090 GPUs computer
• Ryzen 9 3950x + 64 GiB RAM + 1 x RTX 3090 GPU computer

Env setup

Clone this repo and create the input directory:

git clone https://github.com/jamarju/riiid-acp-pub
mkdir input

Unzip the dataset into input or just copy over the required files:

• train.csv
• lectures.csv
• questions.csv

Alternatively, you can just create a symlink from your dataset path to input:

ln -s /your/dataset/path input

Install conda env and run jupyter:

conda env create -f env/env.yaml
conda activate riiid-acp
jupyter notebook --ip 0.0.0.0 --no-browser --NotebookApp.iopub_msg_rate_limit=10000000000

Run notebooks

Run 01_pre.ipynb to preprocess data. A minimum 128 GiB RAM is required (a swapfile is required if your computer has less than 128 GiB of RAM). This will generate the following pkl files in input/

• input/data_v210101b.pkl
• input/meta_v210101b.pkl

Run 02_train.ipynb to train the model. The default parameters will produce an AUROC score of 0.812 using 2.5% holdout validation users.

The script supports distributed training on multi-GPU setups. See the instructions at the beginning of the notebook for the exact steps.

Additionally more models can be trained and later ensembled changing the number of encoder/decoder layers, heads, transformer activation, dropout, T-Fixup initialization and optimizer without further changes to the code by simply changing main's default parameters. Output:

• models/best210105.pth

Run 03_pre_sub.ipynb to prepare data for submission. This will cut down user's historic data to the last 500 interactions. Outputs:

• input/data_500_last_interactions_v210101b.pkl
• input/data_attempt_num_v210101b.npy
• input/data_attempts_correct_v210101b.npy

Run 04_pre_validation_set.ipynb to generate a validation split off of train.csv in a format suitable for the inference script (similar to example_test.csv). Outputs:

• input/validation_x_0.025.csv
• input/validation_y_0.025.csv
• input/validation_submission_0.025.csv

Copy or hard-link the trained models and the following files into kaggle_dataset/root/resources:

ln input/data_500_last_interactions_v210101b.pkl kaggle_dataset/root/resources
ln input/data_attempt_num_v210101b.npy kaggle_dataset/root/resources
ln input/data_attempts_correct_v210101b.npy kaggle_dataset/root/resources
ln input/meta_v210101b.pkl kaggle_dataset/root/resources

For convenience the following two pre-trained models are provided in kaggle/root/resources:

• 210105_0.812154_gelu_e4d4_ep30.pth
• 210105_0.812534_relu_e3e3.pth

At this point, ls -l kaggle_dataset/root/resources should look like this:

-rw-rw-r-- 1 javi javi   79921941 Jan 15 23:06 210105_0.812154_gelu_e4d4_ep30.pth
-rw-rw-r-- 1 javi javi   65210849 Jan 15 23:06 210105_0.812534_relu_e3e3.pth
-rw-rw-r-- 2 javi javi 6811424004 Jan 15 22:54 data_500_last_interactions_v210101b.pkl
-rw-rw-r-- 2 javi javi 6085350128 Jan 15 22:54 data_attempt_num_v210101b.npy
-rw-rw-r-- 2 javi javi 6085350128 Jan 15 22:54 data_attempts_correct_v210101b.npy
-rw-rw-r-- 2 javi javi    1953960 Jan 11 11:12 meta_v210101b.pkl

Build the resources dataset:

cd kaggle_dataset
make

Run 05_inference.ipynb.

If you trained your own models, set the H1 and H2 dicts to the appropriate training hyperparams.

The default inference notebook will attempt to ensemble up to two models with dynamic fallback to single model inference in order to fulfill the allocated time budget (8.75h by default).

It should produce an AUROC=0.816 on the default 0.025 user holdout validation set. Sample output:

10000it [6:32:02,  2.35s/it, model 1=2482136, model 1+2=2482075, eta=6.581/8.726, auroc (pub)=0.816131, auroc (pvt)=0.816148]

The script will also produce a submission.csv file with predictions in the same format as example_sample_submission.csv.

Alternatively, you can convert the notebook into a raw .py script that can be launched from the command line instead of jupyter's ipython interpreter. The execution should run faster and use less RAM this way. See instructions in the notebook.

Thanks to...

• Kaggle and Riiid for organizing this challenging competition
• @wuwenmin for his fast ROC AUC calculation routine