Descriptive (or summary) statistics - Descriptive, or summary, statistics organize and condense observed data so that their main features are easier to understand.
Design effect - A design effect is the ratio of an estimator's variance under a specified sampling design to its variance under a reference simple random sampling design of...
Design of experiments - Design of experiments is the planned organization of interventions, experimental units and measurements to answer a defined question efficiently and credibly.
Detailed balance - Detailed balance is a pairwise flow condition for a Markov chain and a probability distribution.
Detectable difference - A detectable difference is a true population effect that would give a specified statistical test a chosen power under stated design and modeling assumptions.
Detection Bias - Detection bias is a systematic distortion caused by differences in how outcomes are noticed, measured, or classified across groups.
Detection error tradeoff - Detection error tradeoff describes the relationship between false alarms and missed detections as a binary detector's decision threshold changes.
Determinant - The determinant is a scalar associated with a square matrix.
Determiner - A determiner is a grammatical word associated with a noun phrase that helps express how its referent should be understood in context.
Deterministic algorithm - A deterministic algorithm follows rules that produce the same result whenever it starts with the same complete inputs and state.
Deterministic annealing - Deterministic annealing is an optimization method that starts by treating the problem as soft and blurred, then gradually sharpens it, so the search avoids...
Deterministic global optimization - Deterministic global optimization uses systematic mathematical procedures to seek a globally best feasible solution and establish an optimality guarantee...
Deterministic imputation - Deterministic imputation, in the statistical-editing sense used by the OECD glossary, fills a missing or designated field when the other accepted values and...
Deterministic nodes - Deterministic nodes are variables in a graphical model whose values are fixed functions of their parent variables.
Deterministic parser - A deterministic parser follows a single parsing course rather than maintaining several competing analyses at each decision.
Deterministic policy gradient - A deterministic policy gradient is the derivative used to improve a policy that chooses a specific continuous action for each state.
Deterministic Sampling - Deterministic sampling selects records or evaluation points using a specified rule that produces the same selection when its inputs and settings are unchanged.
Deterministic training conditional approximation - The deterministic training conditional approximation, or DTC, is a sparse Gaussian process approximation that makes training function values deterministic...
Detrended correspondence analysis - Detrended correspondence analysis, or DCA, is an ordination method developed to summarize ecological community data while modifying certain patterns...
Development set - A development set is a collection of examples used to guide choices while building a machine-learning system.
Developmental robotics - Developmental robotics studies how robots can acquire abilities progressively through experience, interaction and learning, drawing inspiration from human...
Deviance information criterion - The deviance information criterion, or DIC, is a Bayesian model-comparison measure that combines posterior average fit with an estimate of effective model...
Deviance (statistics) - Deviance is a likelihood-based measure of how much a fitted statistical model falls short of a saturated model that can fit the observed responses exactly.
Deviation scores - Deviation scores express observations as signed distances from their mean. For an observation x and arithmetic mean x-bar, its deviation score is x - x-bar.
Diagnosis - In this machine-learning context, diagnosis means investigating a trained model's performance by comparing training error, validation error and baselines.
Diagnostic analytics - Diagnostic analytics investigates observed outcomes to identify plausible explanations, contributing factors, and problems requiring further examination.
Diagnostic checking - Diagnostic checking is the examination of a fitted model for signs that its assumptions or structure are inadequate for the intended use.
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.