AI training data glossary

The terms you'll meet when buying or licensing AI training data, defined in one sentence each.

Agent trajectory
A step-by-step record of actions taken to complete a task in software, including screens, inputs and results.
AI training data
The examples a machine learning model learns from, such as text, images, audio, video, code, actions and human judgments.
Anonymization
Processing data so no one can identify the people in it by any reasonably likely means.
Benchmark contamination
When test or benchmark data ends up in a model's training data, inflating its scores without improving real ability.
Chain of custody
The record of every party that has held a copy of a dataset, and when, from creation to the current holder.
Data broker
In privacy law, a business selling personal data about people it has no relationship with; in AI data, an intermediary matching data holders with buyers.
Data license
A contract granting a named party defined rights to use a copy of data, for set purposes and terms, while the licensor keeps ownership.
Data manifest
An inventory describing a dataset's contents, sources, volumes, date ranges and rights status, without containing the data itself.
Data provenance
The documented history of a dataset: who created it, how it was collected, under what rights, and what was done to it since.
Dataset card
A structured document describing a dataset's purpose, composition, collection, processing and intended uses.
De-identification
Removing or replacing information that identifies people so data cannot reasonably be linked back to them under a stated standard.
Evaluation dataset
A set of tasks with checked answers used to measure a model's ability, kept separate from training data.
Exclusive license
A license under which only the licensee may use the data for the agreed scope and term, so the owner cannot license it to others.
Expert determination
A HIPAA de-identification method where a qualified expert certifies that the risk of re-identifying individuals is very small.
Fair use
A US copyright doctrine allowing limited use of copyrighted material without permission, judged case by case.
Fine-tuning
Further training a pre-trained model on a smaller, targeted dataset to improve it at specific tasks or domains.
HIPAA safe harbor
A HIPAA de-identification method that removes 18 specified types of identifiers from health information.
Hold-out set
Data deliberately kept out of training so it can test whether a model generalizes to examples it has not seen.
Model collapse
Degradation in model quality when models are trained repeatedly on data generated by other models instead of human data.
Non-exclusive license
A license that lets the owner grant the same rights to other licensees.
Personally identifiable information (PII)
Information that can identify a person directly, such as a name or email, or indirectly when combined with other data.
Pre-training
The first stage of training a foundation model on very large, broad datasets to learn general knowledge and language.
Preference data
Records of which of several model responses a person judged better, often with reasons or rewrites.
Protected health information (PHI)
Individually identifiable health information held by HIPAA covered entities and their business associates.
Pseudonymization
Replacing identifiers with consistent codes so records can be linked to each other but not to a person without a separate key.
Re-identification
Linking de-identified data back to the people it describes, often by combining it with other data.
RL environment
A simulated or copied software setting where an AI agent can attempt tasks repeatedly and be scored, so it learns by trial and error.
RLHF (reinforcement learning from human feedback)
Training a model to produce responses people prefer, using human rankings or ratings of model outputs as the learning signal.
Sublicensing
When a licensee grants rights in licensed data to a further party, such as a customer or contractor.
Success fee
A fee paid to an intermediary only when a transaction completes, usually a share of the deal value.
Supervised fine-tuning (SFT)
Fine-tuning on examples of inputs paired with the desired outputs, often written or checked by people.
Synthetic data
Data generated by models or simulations rather than collected from real people or systems.