Training

To train a model with Ludwig, we first need to create a Ludwig configuration. The config specifies input features, output features, preprocessing, model architecture, training loop, hyperparameter search, and backend infrastructure -- everything that's needed to build, train, and evaluate a model.

At a minimum, the config must specify the model's input and output features.

For now, let's use a basic config that just specifies the inputs and output and leaves the rest to Ludwig:

rotten_tomatoes.yaml

input_features:
    - name: genres
      type: set
      preprocessing:
          tokenizer: comma
    - name: content_rating
      type: category
    - name: top_critic
      type: binary
    - name: runtime
      type: number
    - name: review_content
      type: text
      encoder: 
          type: embed
output_features:
    - name: recommended
      type: binary

This config file tells Ludwig that we want to train a model that uses the following input features:

• The genres associated with the movie will be used as a set feature
• The movie's content rating will be used as a category feature
• Whether the review was done by a top critic or not will be used as a binary feature
• The movie's runtime will be used as a number feature
• The review content will be used as text feature

This config file also tells Ludwig that we want our model to have the following output features:

• The recommendation of whether to watch the movie or not will be output as a binary feature

Once you've created the rotten_tomatoes.yaml file with the contents above, you're ready to train your first model:

CLIPythonDocker CLI

ludwig train --config rotten_tomatoes.yaml --dataset rotten_tomatoes.csv

from ludwig.api import LudwigModel
import pandas

df = pandas.read_csv('rotten_tomatoes.csv')
model = LudwigModel(config='rotten_tomatoes.yaml')
results = model.train(dataset=df)

mkdir rotten_tomatoes_data
mv rotten_tomatoes.yaml ./rotten_tomatoes_data
mv rotten_tomatoes.csv ./rotten_tomatoes_data
docker run -t -i --mount type=bind,source={absolute/path/to/rotten_tomatoes_data},target=/rotten_tomatoes_data ludwigai/ludwig train --config /rotten_tomatoes_data/rotten_tomatoes.yaml --dataset /rotten_tomatoes_data/rotten_tomatoes.csv --output_directory /rotten_tomatoes_data

Note

In this example, we encoded the text feature with an embed encoder, which assigns an embedding for each word and sums them. Ludwig provides many options for tokenizing and embedding text like with CNNs, RNNs, Transformers, and pretrained models such as BERT or GPT-2 (provided through huggingface). Using a different text encoder is simple as changing encoder option in the config from embed to bert. Give it a try!

input_features:
    - name: genres
      type: set
      preprocessing:
          tokenizer: comma
    - name: content_rating
      type: category
    - name: top_critic
      type: binary
    - name: runtime
      type: number
    - name: review_content
      type: text
      encoder: 
          type: bert
output_features:
    - name: recommended
      type: binary

Ludwig is very flexible. Users can configure just about any parameter in their models including training parameters, preprocessing parameters, and more, directly from the configuration. Check out the config documentation for the full list of parameters available in the configuration.