An ontology (sometimes called a taxonomy) helps define how unstructured data should be annotated for use in model training.

An ontology contains all of the information to render a set of features and the relationships between them. Ontologies can be reused across different projects and they are required for data labeling, model training, and evaluation. When you are in the editor, the ontology is what appears in the Tools panel.

Why are Ontologies important?

A clean, thoughtful ontology is critical for creating high-quality labeled data with minimal errors and inconsistencies. Ontologies are an essential part of the Labelbox labeling platform. Every time you create a project or a model in Labelbox, you will need to select an ontology.

A good ontology defines the following for your labeling team:

What should the labeling team be labeling?
What are the objects of interest or classification tasks that your labeling team should use to label the unstructured data? Think of the ontology as a blueprint of the structure you want to apply to the data in order to train your model.

How should objects or classifications be labeled?
Your ontology should specify how you expect things to be labeled for your model. As an example, should an object be labeled with a bounding box, polygon, or segmentation mask? For classification tasks, what are the options for how something should be classified?

What additional information is helpful for your model or review team to know?
Sometimes there is secondary or tertiary information that is helpful to know about the data during labeling (e.g., the quality of the image).

For example, let's say you are training a model to identify dogs and cats on images. You create "Ontology 1" and specify that the labelers should label the dogs and cats with bounding boxes. Furthermore, you know that blurry images can affect your model performance, so it includes a classification option for the labeler to indicate whether the image is blurry.

Now let's say you have a new project to identify dogs and llamas. You decided to re-use some components from your old ontology and name it "Ontology 2". In "Ontology 2" you replace the object of "cat" with a new object for "llama".


Global ontologies

Ontologies can be accessed at the organization level and re-used across multiple projects. You can view and modify your ontologies by navigating to Schema > Ontologies.