Multistage Sampling - Multistage sampling selects a sample through two or more successive levels of sampling units.
Multiway data analysis - Multiway data analysis studies data organized along several distinct dimensions, often three or more, while retaining their joint structure.
Mutable Data Types - Mutable data types are types whose objects can have their contents or state changed after creation.
Mutually Exclusive Events - Mutually exclusive events are events that cannot occur together in the same defined outcome.
Nearest neighbor search - Nearest neighbor search finds the stored item or items closest to a query according to a specified distance or similarity measure.
Necessary condition analysis - Necessary condition analysis, or NCA, is an approach for investigating whether a condition constrains the level of an outcome: without enough of the...
Negative testing - Negative testing checks how software behaves when it receives invalid inputs or encounters conditions outside its intended normal use.
Numeric prediction - Numeric prediction is the task of estimating a numerical quantity from available information.
Objective function - An objective function is a mathematical rule that assigns a value to a candidate solution so an optimization process can seek a minimum or maximum.
Offset filtration - An offset filtration is a nested family of shapes formed by expanding equal-radius neighborhoods around a set of points as the radius increases.
Open coding - Open coding is an exploratory qualitative-analysis process in which a researcher examines data closely and develops initial labels for concepts, actions or...
Open data index - An open data index is a structured assessment of how openly selected datasets are published.
Operational analytical processing - Operational analytical processing uses data analysis to support decisions within ongoing operations.
Operational reporting - Operational reporting presents information about day-to-day activities so that people can monitor work, identify exceptions and decide what needs attention.
Optimal matching - Optimal matching, in sequence analysis, measures how different two ordered sequences are by finding the least costly set of insertions, deletions and...
Ordinal variable - An ordinal variable is a categorical variable whose categories have a meaningful order.
Outlier - An outlier is an observation that is unusually different from the other observations or from the pattern expected under a specified model.
p-hacking - P-hacking is the practice of selecting or changing data analyses in response to their results so that a desired finding appears statistically significant...
Percentile Bootstrap Confidence Interval - A percentile bootstrap confidence interval estimates uncertainty by repeatedly resampling the observed data, recalculating a statistic and taking specified...
Persistence barcode - A persistence barcode is a collection of intervals that records when topological features appear and disappear as a parameter changes.
Persistence module - A persistence module is an indexed family of algebraic objects together with maps that describe how information passes from one index to later indices.
Persistent Betti number - A persistent Betti number counts the independent homology classes present at an earlier filtration parameter that remain nonzero and independent at a later...
Persistent homology group - A persistent homology group is the image of the homology map from an earlier stage of a filtration to a later stage.
Pie chart - A pie chart is a circular chart divided into slices that show how categories contribute to one whole.
Pivot table - A pivot table is a summary table that groups source records by selected categories and calculates measures such as sums, counts or averages.
Post hoc analysis - Post hoc analysis is analysis undertaken after results have been examined, often to explore an unexpected pattern or investigate a broader finding in more...
Predictive analytics - Predictive analytics uses data and statistical or machine-learning methods to estimate future or otherwise unknown outcomes.
Prescriptive analytics - Prescriptive analytics uses data, models and decision rules to recommend actions for a stated objective while accounting for constraints and trade-offs.
Principal component analysis - Principal component analysis, or PCA, transforms numerical variables into new, mutually perpendicular directions ordered by how much variation they capture.
Probabilistic Sampling - Probabilistic sampling, usually called probability sampling, selects units through a random mechanism with known, positive inclusion probabilities for the...
Q-Q plot - A Q-Q plot, or quantile-quantile plot, compares corresponding quantiles of two distributions.
Quartile - A quartile is a cut point in an ordered distribution associated with quarters of its cumulative probability.
Randomized Response - Randomized response is a data-collection technique that deliberately introduces known randomness into individual answers so that researchers can estimate an...
Range - In descriptive statistics, the range is the largest observed value minus the smallest observed value.
Real-time business intelligence - Real-time business intelligence is the use of frequently updated data and analysis to support business decisions while the information is still...
Real-time data - Real-time data is data made available soon enough after the underlying event or observation to support its intended immediate use.
Response Bias - Response bias is a systematic distortion in the answers people provide, causing recorded responses to differ from what the study intends to measure.
Sample Standard Deviation - The sample standard deviation measures the spread of observed numerical values around their sample mean.
Scatter plot - A scatter plot displays paired numerical values as points on two axes.
Sequence analysis in social sciences - Sequence analysis in the social sciences studies ordered histories of states or events to understand how social processes unfold.
Sequential pattern mining - Sequential pattern mining discovers recurring ordered patterns within a collection of sequences.
Seriation (statistics) - Seriation is the arrangement of objects into an order that reveals structure in their data or relationships.
Slice - A slice selects part of a sequence using a start position, a stopping boundary and an optional step. In Python, the usual notation is sequence[start:stop:step].