Machine learning device, inference device, and machine learning method

An inference device comprising:

• a first task input unit that selects one task from a plurality of tasks;
• an inference model generation unit that generates an inference neural network model in which weights in a neural network model trained on the plurality of tasks other than weights used in the task selected are set to 0;
• and
• an inference unit that infers the task selected, based on the inference neural network model.

A machine learning method comprising:

• determining, in accordance with a depth of a layer in a neural network model, a first initialization rate for initializing weights in the neural network model on a first task;
• generating a neural network model trained on a first task by training on the first task by machine learning;
• and
• initializing weights in the neural network model trained on the first task, based on the first initialization rate, to generate an initialized neural network model trained on the first task, the initialized neural network trained on the first task being used in a second task.