DE MLO study materials
DE MLO study resources

DE MLO key terms

DE MLO · Get comfortable with the vocabulary.

Experiment Run

A single execution of a training or evaluation script, identified by a unique ID and recording its parameters, metrics, artifacts, and code version so results can be compared later.

Related: Run Metadata, Artifact Lineage, Model Registry
Run Metadata

Structured facts attached to a run, such as hyperparameters, dataset identifiers, git commit, environment, and tags, used to filter, group, and audit experiments.

Related: Experiment Run, Hyperparameter, Reproducibility Manifest
Metric Logging

Recording scalar or series values over time during training, such as loss and accuracy per step, so curves can be compared across runs and checked for convergence.

Related: Experiment Run, Model Drift
Artifact

Any file produced or consumed by a run, such as a model checkpoint, dataset snapshot, or evaluation report, stored with a content hash and version for traceability.

Related: Artifact Lineage, Model Registry
Artifact Lineage

The recorded graph of which inputs produced which outputs, linking datasets, code, runs, and model versions so any deployed model can be traced back to its origins.

Related: Artifact, Reproducibility Manifest, Model Registry
Model Registry

A central catalog that stores model versions with their metadata and stage labels, supporting promotion, rollback, and controlled handoff between training and serving teams.

Related: Model Version, Model Staging, Artifact Lineage
Model Version

An immutable snapshot of a trained model's weights and configuration, identified by a unique number or hash so results and deployments can be referenced unambiguously.

Related: Model Registry, Model Staging, Rollback
Model Staging

Moving a model version through lifecycle labels such as development, staging, production, or archived, with gates and approvals required before each promotion step.

Related: Model Registry, Model Version, Rollback
Rollback

Reverting a serving deployment to a previously validated model version when the new one degrades quality or fails health checks, restoring service quickly.

Related: Model Version, Canary Deployment, Model Drift
Checkpoint

A saved copy of model weights and optimizer state at a training step, enabling resumption after failure and selection of the best-performing iteration.

Related: Early Stopping, Artifact
Hyperparameter

A configuration value set before training, such as learning rate, batch size, or number of layers, that governs the learning process rather than being learned from data.

Related: Hyperparameter Tuning, Run Metadata
Hyperparameter Tuning

Systematically searching combinations of configuration values, using grid, random, or Bayesian methods, to improve a validation metric within a compute budget.

Related: Hyperparameter, Early Stopping, Overfitting
Learning Rate Schedule

A rule that changes the learning rate during training, such as warmup followed by decay, to improve stability and final convergence quality.

Related: Hyperparameter, Gradient Descent
Gradient Descent

An optimization procedure that iteratively updates model parameters in the direction that reduces the loss, using gradients computed on batches of training data.

Related: Learning Rate Schedule, Batch Size
Batch Size

The number of training examples processed before one parameter update, trading off memory use, throughput, and the noise level of gradient estimates.

Related: Gradient Descent, Hyperparameter
Overfitting

A condition where a model fits training data noise so closely that it generalizes poorly to unseen data, visible as a widening gap between training and validation metrics.

Related: Regularization, Early Stopping, Validation Set
Regularization

Techniques such as weight decay, dropout, or data augmentation that constrain model complexity to reduce overfitting and improve performance on unseen examples.

Related: Overfitting, Early Stopping
Early Stopping

Halting training when a validation metric stops improving for a set number of epochs, preventing overfitting and saving compute while preserving the best checkpoint.

Related: Overfitting, Checkpoint, Validation Set
Validation Set

A held-out portion of labeled data used to tune hyperparameters and select models, kept separate from training and final test data to avoid optimistic bias.

Related: Overfitting, Early Stopping, Data Leakage
Data Leakage

Accidental inclusion of information from the target or test period in training features, producing unrealistically high evaluation scores that collapse in production.

Related: Validation Set, Model Drift
Feature Engineering

Creating and transforming input variables, through scaling, encoding, aggregation, or domain-derived ratios, so a model can learn patterns more effectively.

Related: Training-Serving Skew, Feature Store
Transfer Learning

Starting from a model pretrained on a large related dataset and fine-tuning it on a smaller target dataset, reducing data and compute requirements.

Related: Fine-Tuning, Checkpoint
Fine-Tuning

Further training of a pretrained model on task-specific data, often with a smaller learning rate, to adapt its learned representations to a new objective.

Related: Transfer Learning, Hyperparameter
Model Serving

Running a trained model behind an interface that accepts requests and returns predictions, with concerns for latency, throughput, and availability.

Related: Inference Endpoint, Batch Inference, Canary Deployment
Inference Endpoint

A network address and API, often HTTP or gRPC, that exposes a deployed model for real-time prediction requests from applications.

Related: Model Serving, Latency
Batch Inference

Scoring large volumes of records on a schedule using a deployed model, trading immediate response for higher throughput and lower per-record cost.

Related: Model Serving, Inference Endpoint
Latency

The time between sending a prediction request and receiving the response, a key service-level measure for interactive applications and autoscaling decisions.

Related: Inference Endpoint, Throughput
Throughput

The number of prediction requests or records a serving system processes per unit time, constrained by hardware, batching, and model size.

Related: Latency, Batch Inference
Canary Deployment

Releasing a new model version to a small fraction of live traffic first, comparing error rates and metrics before widening exposure or rolling back.

Related: Rollback, Shadow Deployment, A/B Test
Shadow Deployment

Running a candidate model in parallel with the live model on real requests without returning its output, to compare behavior safely before promotion.

Related: Canary Deployment, Model Monitoring
A/B Test

A controlled experiment splitting traffic between model variants and comparing a business or quality metric to decide which version performs better.

Related: Canary Deployment, Model Monitoring
Training-Serving Skew

A mismatch between how features are computed during training and during live prediction, causing production accuracy to fall below offline evaluation.

Related: Feature Store, Feature Engineering, Model Drift
Feature Store

A shared system that computes and stores feature values consistently for both training pipelines and online serving, reducing skew and duplicated logic.

Related: Training-Serving Skew, Feature Engineering
Model Monitoring

Continuous tracking of a deployed model's inputs, outputs, errors, and latency to detect degradation and trigger investigation or retraining.

Related: Model Drift, Data Drift, Alerting Threshold
Model Drift

A decline in predictive performance over time as the relationship between inputs and target changes in the real world after deployment.

Related: Data Drift, Model Monitoring, Retraining Trigger
Data Drift

A change in the statistical distribution of input features compared with the training data, which may or may not yet affect prediction quality.

Related: Model Drift, Model Monitoring
Retraining Trigger

A predefined condition, such as drift score or accuracy drop exceeding a threshold, that automatically starts a new training cycle.

Related: Model Drift, Model Monitoring, Alerting Threshold
Alerting Threshold

A configured limit on a monitored signal that, when crossed, notifies operators so they can investigate before users are significantly affected.

Related: Model Monitoring, Retraining Trigger
Reproducibility Manifest

A complete record of code commit, dependency versions, data snapshot, random seeds, and hardware needed to recreate a training run exactly.

Related: Artifact Lineage, Run Metadata, Random Seed
Random Seed

A value initializing pseudo-random number generators so that data shuffling, weight initialization, and sampling repeat identically across runs.

Related: Reproducibility Manifest, Experiment Run
Model Card

A short document describing a model's intended use, training data, evaluation results, limitations, and ethical considerations for downstream consumers.

Related: Model Registry, Reproducibility Manifest
Data Provenance

The documented origin and processing history of a dataset, including sources, transformations, and access controls, supporting audit and compliance review.

Related: Artifact Lineage, Reproducibility Manifest
Access Control

Rules assigning permissions so that only authorized users and services can read, modify, or deploy models, data, and experiment records.

Related: Model Registry, Data Provenance