Diagonal linear discriminant analysis - Diagonal linear discriminant analysis, or DLDA, is a classification method that uses class-specific means and a shared diagonal covariance matrix.
Dialogue act - A dialogue act is the communicative function performed by an utterance or part of an utterance in a conversation.
Diameter - In graph theory, the diameter is the greatest shortest-path distance between nodes in a graph.
Dichotomic search - Dichotomic search is a search process that narrows its possibilities by choosing between two alternatives at each decision step.
Dichotomous thinking - Dichotomous thinking reduces a question to two opposing categories while overlooking meaningful degrees, uncertainty or alternative interpretations.
Dichotomous variables - Dichotomous variables are variables with two possible categories or values.
Dichromatic model - The dichromatic model, in computer vision, commonly refers to the dichromatic reflection model that describes observed surface color as a combination of...
Dictionary - In the natural-language-processing sense used here, a dictionary is a structured resource that records words or expressions and information about them.
Dictionary-based machine translation - Definition: Dictionary-based machine translation translates source expressions by looking up corresponding target-language entries in a bilingual dictionary.
Dictionary coder - A dictionary coder is a compression method that replaces selected sequences of symbols with references to a dictionary or to previously available data.
Difference-equation filtering - Difference-equation filtering computes a discrete-time output from weighted current and past inputs and, in recursive filters, past outputs.
Difference-map algorithm - The difference-map algorithm is an iterative method for searching for a point that satisfies two sets of constraints simultaneously.
Difference scores - Difference scores are values obtained by subtracting one measurement from a corresponding second measurement.
Differencing - Differencing is a time-series transformation that replaces observations with changes between observations at a specified lag.
Differentiable cross-entropy method - The differentiable cross-entropy method, or DCEM, is a differentiable variant of a sampling-based optimization method.
Differentiable image pipeline - A differentiable image pipeline is a sequence of image-processing operations through which useful derivatives can be computed with respect to inputs or...
Differentiable neural computer - A differentiable neural computer, or DNC, is a memory-augmented neural architecture that combines a neural controller with an external, addressable memory.
Differentiable programming - Differentiable programming is an approach to designing numerical programs whose outputs can be differentiated with respect to selected inputs or parameters.
Differential entropy - Differential entropy is an information-theoretic quantity defined for a continuous probability distribution with a density.
Differential heuristic - A differential heuristic estimates the remaining shortest-path cost by comparing precomputed distances to selected landmark nodes.
Differential privacy - Differential privacy is a mathematical framework for limiting how much the output of an analysis can reveal about the contribution of a particular protected...
Differential return - Differential return is a reward-based quantity used in continuing, average-reward reinforcement learning.
Differential validity - Differential validity concerns whether the relationship between a score or predictor and an intended outcome differs across groups.
Differential value function - A differential value function describes expected future reward relative to a policy's long-run average reward in a continuing task.
Differentially private stochastic gradient descent - Differentially private stochastic gradient descent, or DP-SGD, is a training procedure that limits individual training examples' influence by clipping their...
Diffusion model - A diffusion model is a generative model that learns to produce data through a process related to reversing progressive corruption.
Digidot chart - A digidot chart combines a stem-and-leaf display with a time-order plot of the same numerical observations.
Digit recognition - Digit recognition is the task of identifying digits from an input signal.
Digital continuity - Digital continuity is the ability to keep digital information usable for the purposes and period for which it is needed.
Digital curation - Digital curation is the active management of digital material throughout its lifecycle so that it remains understandable, trustworthy and usable for its...
Digital divide - The digital divide is unequal access to, ability to use, or benefit from digital technologies and information.
Digital elevation map - A digital elevation map is a digital representation of surface elevation across geographic locations, commonly stored as a grid of height values.
Digital geometry - Digital geometry studies the shapes, positions, and geometric properties of objects represented on discrete spaces, such as the grid of pixels in an image...
Digital image - A digital image is a visual representation encoded as data that a computer can store, process, and display.
Digital object memory - A digital object memory is an organized collection of digital information associated with an individual physical object over time.
Digital obsolescence - Digital obsolescence is the loss or weakening of practical access to digital material because the technologies needed to read, interpret or use it are no...
Digital organism - A digital organism is a self-replicating computer program studied in an artificial-life environment where replication, variation and selection can occur.
Digital topology - Digital topology studies connectivity, boundaries, holes, and related structural properties of objects represented on discrete grids.
Digital watermarking - Digital watermarking embeds an identifying or informative signal into digital content so that the signal can later be seen, detected, or recovered.
Digitization - Digitization is converting information from a physical or analog form into a digital representation that a computer can store and process.
Dijkstra's algorithm - Dijkstra's algorithm finds minimum-total-cost paths from a starting node in a weighted graph whose edge weights are nonnegative.
Dimensional fact model - The Dimensional Fact Model, or DFM, is a graphical conceptual model used to design data warehouses.
Dimensionality - Dimensionality is the number of input fields a model must consider at once: one field is one dimension, a spreadsheet with two hundred columns is two...
Dimensionality reduction - Dimensionality reduction represents data using fewer features or coordinates than the original representation.
Dinitz - Dinitz is a maximum-flow algorithm that increases the amount of a single commodity sent from a source to a sink while respecting edge capacities and flow...
Diphthong - A diphthong is a vowel whose quality changes noticeably during its production within a single syllable.
Direct sampling - Direct sampling, in the OECD glossary's survey-statistics sense, means that sampled units are actual members of the population being studied and information...