Item-item collaborative filtering - Item-item collaborative filtering is a recommendation approach that uses relationships between items inferred from users' interactions or ratings.
Item matrix - An item matrix is a collection of learned item representations used in a matrix-factorization recommender.
Item response theory - Item response theory (IRT) is a family of statistical models that relates responses to individual questions or tasks to an unobserved ability or trait and...
Item stem and leaf plot - An item stem and leaf plot is a questionnaire display that places question identifiers at positions corresponding approximately to their average scores on a...
Item-total correlation - Item-total correlation measures the association between responses to one questionnaire or test item and a score formed from a set of items.
Item tree analysis - Item tree analysis, or ITA, is an exploratory method for investigating hierarchical relationships among questionnaire or test items from response patterns.
Iterated extended Kalman filter - The iterated extended Kalman filter refines an extended Kalman filter's measurement update by repeatedly linearizing the observation model around an...
Iterated local search - Iterated local search is an optimization framework that repeatedly improves a solution locally, perturbs it, improves the perturbed solution, and decides...
Iteration - An iteration is one complete round of an improvement process: one training update, one tuning cycle or one review pass, after which the result is measured...
Iterative deepening search - Iterative deepening search repeatedly performs depth-limited depth-first searches with increasing depth limits until it finds a goal or establishes failure.
Iterative expansion - Iterative expansion, or IE, is a memory-bounded heuristic search algorithm developed by Stuart Russell.
Iterative method - An iterative method is a numerical procedure that constructs a sequence of approximate answers by repeatedly applying an update rule.
Iterative rational Krylov algorithm - The iterative rational Krylov algorithm, or IRKA, constructs a smaller linear dynamical model by repeatedly updating interpolation points using the poles of...
Iterative soft thresholding algorithm - The iterative soft thresholding algorithm, often called ISTA or iterative shrinkage-thresholding, solves certain optimization problems by alternating a...
Iteratively Reweighted Least Squares - Iteratively Reweighted Least Squares is a fitting method that solves certain regression problems by repeatedly solving a weighted least-squares problem...
Jaccard similarity coefficient score - The Jaccard similarity coefficient score measures overlap between two sets by dividing the size of their intersection by the size of their union.
Jackknife variance estimates for random forest - Jackknife variance estimates for random forests are methods for estimating how much a forest's prediction would vary across repeated training samples.
Jacobi method - The Jacobi method is an iterative algorithm for solving a linear system Ax=b.
Jacobian - The Jacobian is the matrix of first-order partial derivatives of a vector-valued function.
Jacobian-vector product - A Jacobian-vector product, or JVP, multiplies a function's Jacobian at a chosen input by an input-direction vector.
Jarvis&Patrick clustering - Jarvis-Patrick clustering is a clustering method that groups items by shared near neighbors: two items belong together when they appear high on each other's...
JDBC-ODBC bridge - The JDBC-ODBC bridge is a driver layer that allows Java applications using JDBC, Java Database Connectivity, to access data through an ODBC driver.
Jeffreys prior - A Jeffreys prior is a Bayesian prior constructed from the expected Fisher information of a statistical model.
Jenkins - Traub algorithm - The Jenkins-Traub algorithm is a family of numerical methods for finding polynomial zeros through three stages of auxiliary-polynomial iteration.
Jenks natural breaks optimization - Jenks natural breaks optimization is a method for dividing ordered numerical values into a chosen number of classes.
Jensen bound integration - Jensen bound integration is a technique for approximating an average that is hard to compute exactly: it uses Jensen's inequality, which relates the average...
Job-shop scheduling problem - A job-shop scheduling problem asks when to perform the operations of several jobs on shared machines while respecting each job's required operation order...
Johnson's algorithm - Johnson's algorithm computes shortest paths between all pairs of vertices in a weighted graph.
Join Method - A join method is the physical algorithm a database uses to combine rows from query inputs according to a join condition.
Join-pattern - A join-pattern is a concurrency construct that specifies a reaction requiring messages or calls on several channels together.
Join tree - A join tree is a tree of variable sets or clusters arranged so that every variable appears in a connected group of tree nodes.
Joint action - A joint action is a combination of actions, one for each participating agent, considered together at a decision step.
Joint compatibility branch and bound - Joint compatibility branch and bound, commonly abbreviated JCBB, is a data-association method that searches for a large set of mutually compatible matches...
Joint plan - A joint plan describes coordinated actions for multiple agents so that their combined execution achieves specified goals.
Joint probability - Joint probability is the probability that specified events all occur. For two events A and B, it is written P(A and B), or P(A intersection B).
Joint probability distribution - A joint probability distribution describes how two or more random variables behave together.
Joint source and channel coding - Joint source and channel coding designs information representation and protection against transmission noise together.
Jonckheere's trend test - Jonckheere's trend test, also called the Jonckheere-Terpstra test, is a nonparametric test for an ordered alternative across independent groups.
JTMS - JTMS stands for justification-based truth maintenance system.
Judgment sample - A judgment sample is a non-probability sample whose members are deliberately selected using a researcher's or expert's assessment of their relevance or...
Jump point search - Jump point search, or JPS, is a pathfinding technique that reduces redundant search on suitable grid maps.
Jump search - Jump search is a lookup algorithm for sorted data that checks spaced block boundaries until it locates the block that could contain a target, then searches...
Junction tree algorithm - The junction tree algorithm is a method for exact probabilistic inference in suitable graphical models.
Justification - A justification is an explicit record of the reasons or conditions supporting a conclusion.
k-anonymity - k-anonymity is a property of a released table in which each record shares its combination of designated quasi-identifier values with at least k − 1 other...
K-components - K-components are maximal parts of an undirected graph whose node connectivity is at least k.
k-d tree - A k-d tree is a binary spatial index that recursively divides points using coordinate-aligned boundaries.