Artificial intelligence and data

One big table

One Big Table (OBT), also called wide table or super table, is a denormalized data modeling approach flattening facts and dimensions into one wide join-free table for analytics, best for 1-3 filter dimensions and as a serving layer above a star schema.

One-class support vector machine

The one-class support vector machine, also called One-Class SVM or OCSVM, is an unsupervised machine learning algorithm for novelty detection, introduced by Bernhard Schölkopf and colleagues in 2001.

One-hot

One-hot encoding, also called one-of-K or dummy encoding, represents a categorical variable as a vector with a 1 for the instance's category and 0 elsewhere.

One-way function

A one-way function is a function that is easy to compute on every input but hard to invert, the foundational assumption of modern cryptography that has never been proved to exist.

Onehouse

Onehouse Inc is a Sunnyvale, California data infrastructure company founded in 2021 by Vinoth Chandar, creator of Apache Hudi at Uber. Its managed lakehouse service runs in customers' own cloud accounts, supporting Hudi, Iceberg, and Delta Lake, with $68M raised.

Online algorithm

An online algorithm, also known as online computation, is an algorithm that must decide as input arrives piece by piece, without knowledge of future input, unlike an offline algorithm.

Online analytical processing

Online analytical processing (OLAP), a database technology named by E.F. Codd in 1993, organizes business data into multidimensional cubes supporting operations such as drill-down and slice.

Online continual learning

Online continual learning (OCL) is a machine learning setting in which a model learns from a continuous data stream in a single pass, retaining old tasks using a small replay buffer.

Online encyclopedia

An online encyclopedia is a reference work offering alphabetically organized summaries of knowledge over the internet, ranging from volunteer-written Wikipedia to subscription products like Encyclopaedia Britannica Online.

Online machine learning

Online machine learning, also called on-line learning, is a family of machine learning methods that builds predictive models by processing data one instance at a time in arrival order.

Online transaction processing

Online transaction processing (OLTP) is a class of data processing that executes business transactions, such as payments, reservations, and order entries, in real time, confirming each one immediately.

ONNX

ONNX (Open Neural Network Exchange) is an open specification allowing machine learning models to run across different runtimes and hardware. It was announced in 2017 by Facebook, Microsoft, and AWS.

ONNX Runtime

ONNX Runtime is an open-source, cross-platform inference engine for ONNX machine learning models, developed by Microsoft and open sourced in December 2018. It runs models on servers, mobile devices, and browsers.

Ontology (information science)

In information science, an ontology is a formal, machine-readable vocabulary of terms for a domain, standardized in the W3C Web Ontology Language (OWL), part of the Semantic Web.

Ontology alignment

Ontology alignment is a knowledge engineering method that finds correspondences between semantically related entities of two ontologies, so data described with different vocabularies can be interpreted together.

Ontology learning

Ontology learning is a family of semi-automatic methods that extract concepts, relations, and axioms from text or data to build ontologies, first framed by Maedche and Staab in 2001.

Ontology mapping

Ontology mapping, also called ontology matching or alignment, is a knowledge-representation method that finds correspondences between entities of different ontologies so data described with one vocabulary can be interpreted with another.

Open addressing

Open addressing, also called closed hashing, is a hash-table collision-resolution technique that stores all elements in the table's array, resolving collisions by probing for empty slots.

Open Catalyst 2022 (OC22) dataset

The Open Catalyst 2022 (OC22) dataset is a public set of 62,331 density functional theory relaxations of adsorbates on oxide surfaces for training machine learning electrocatalyst models.

Open data

Open data is data anyone is free to use, reuse, and redistribute without legal, technological, or social restriction, most often data from public bodies such as governments.

Open Data Contract Standard

Open Data Contract Standard (ODCS), a Bitol/Linux Foundation vendor-neutral YAML format for data contracts describing dataset schema, quality, SLAs, ownership, and servers; current version v3.2.0; successor to the deprecated Data Contract Specification.

Open Data Product Standard

Open Data Product Standard (ODPS), Bitol's open YAML specification for describing data products (identity, ports, team, AI-agent context), current version v1.1.0; sister of ODCS; distinct from the Open Data Product Specification at opendataproducts.org.

Open Database Connectivity

Open Database Connectivity (ODBC) is a standard API, first released by Microsoft in 1992, that lets one application access many database systems with the same code.

Open Graph Benchmark

The Open Graph Benchmark (OGB) is a 2020 Stanford collection of large-scale benchmark datasets for graph machine learning, covering node, link, and graph prediction tasks with standardized evaluation and public leaderboards.

Open Images dataset

Open Images is a computer vision dataset released by Google Research in 2016, with about 9 million Flickr images annotated with labels, bounding boxes, segmentation masks, and relationships.

Open information extraction

Open information extraction is a natural language processing method that extracts relational tuples of arguments and predicates from text without predefined relation types, introduced in 2007.

Open letter on artificial intelligence (2015)

The open letter on artificial intelligence of 2015, published by the Future of Life Institute, urges research to keep AI robust and beneficial and drew thousands of signatories.

Open Quantum Materials Database

The Open Quantum Materials Database (OQMD) is a free database of density functional theory calculations on inorganic materials, maintained by the Wolverton group at Northwestern University.

Open Reaction Database

The Open Reaction Database (ORD) is an open-access repository and schema for organic reaction data, begun in 2019 to support machine learning for reaction prediction and synthesis planning.