Model types

[duckontheweb]

The main model spec defines a list of allowed Model Type values that are designed to capture the type of model in more detail than than the Algorithm Type.

Opening this issue to discuss the following:

• Is "Model Type" is the appropriate name for this field?
• Should there be any changes to the listed values?
• Should we allow other, user-defined values or require one of the listed values?
• Should we be more explicit about relationships between this field and the Algorithm Type field?

[calebrob6]

Is "Model Type" is the appropriate name for this field?

It seems reasonable! "Target type" might be another appropriate name.

Two thoughts here:

• Multi-task models do not fit well. For example, models trained on the xBD dataset (https://arxiv.org/pdf/1911.09296.pdf) might need to segment buildings and predict image level damage labels. Here a model might be segmentation and classification!
• Unsupervised models that use some sort of contrastive loss also do not fit well. For example, if an unsupervised model uses a triplet loss what should its "Model type" be?

[HamedAlemo]

Good points Caleb.

• For the Multi-task models, the solution can be to allow "Model Type" to have a list of types.
• For the unsupervised example, doesn't fall under "Dimensionality Reduction"? We can also add "Embedding", but it's kind of the same thing.
  Also note that the value for "Model Type" has a set of pre-defined values but for edge cases like this modeler can use/suggest a different type.

[duckontheweb]

• For the unsupervised example, doesn't fall under "Dimensionality Reduction"?

#21 changed the model_type field to a prediction_type field in the model_type object. We don't currently have "Dimensionality Reduction" listed as an option in the "Prediction Type" section, but maybe we should. @calebrob6 if we add this, it seems like your suggestion of using target_type might be more appropriate than using prediction_type since dimensionality reduction doesn't really represent a "prediction."

[sfoucher]

In computer vision, The term task, instead of model_type, is more usual in the ML field, regarding the the listed values, we can sometimes find also the term Instance detection / Instance segmentation.: