Glossary
Searchable terminology from accessibility, web standards, and related fields.
16 results found in Statistics.
- Bonferroni Correction (Bonferroni Adjustment)
- The Bonferroni correction is a statistical adjustment that controls the family-wise error rate when multiple hypothesis tests are performed on the same data. It divides the target significance thresho…
- Chernoff Faces (Chernoff's Faces)
- A visualisation technique introduced by Herman Chernoff in 1973 that represents multivariate data by mapping each data variable to a facial feature — eye size, eye spacing, nose length, mouth curvatur…
- Cumulative Link Mixed Model (CLMM, Ordinal Mixed Model)
- A statistical model for analysing ordinal outcome data (such as Likert-scale ratings) that includes both fixed effects (experimental conditions) and random effects (participants, stimuli). CLMMs use a…
- DBSCAN (Density-Based Spatial Clustering of Applications with Noise)
- A density-based clustering algorithm introduced by Ester, Kriegel, Sander, and Xu (1996) that groups data points located in dense neighbourhoods and labels sparse points as noise. Unlike k-means, DBSC…
- Friedman Test (Friedman Rank Test)
- The Friedman test is a non-parametric statistical test used to detect differences across three or more related samples - for example, the same participants rating three interface conditions. It ranks …
- Inter-Annotator Agreement (IAA, Inter-rater agreement, Inter-coder agreement)
- A statistical measure of how consistently two or more human annotators assign the same label to the same data item, widely used in NLP, computer vision, and AI dataset construction as a proxy for labe…
- Krippendorff's Alpha (Krippendorff Alpha, Kalpha)
- A statistical measure of inter-rater agreement used to assess how consistently two or more coders classify the same qualitative data. Developed by Klaus Krippendorff, the metric handles any number of …
- Minimum Clinically Important Difference (MCID, Minimal Clinically Important Difference)
- The smallest change in a measurement that is perceived as beneficial or meaningful from a clinical perspective. MCID thresholds help researchers and clinicians distinguish statistically significant ch…
- Multivariate Data (Multivariate Dataset, High-Dimensional Data)
- Data in which each observation or sample has more than two measured variables (dimensions). Analysing multivariate data is a core task in statistics, science, and business intelligence, but presenting…
- Pointwise Mutual Information (PMI)
- A statistical measure used in natural language processing to quantify the strength of association between two words based on how much more frequently they co-occur in a corpus than would be expected b…
- Randomization Test (Randomisation Test, Permutation Test)
- A randomization test (also called a permutation test) is a non-parametric statistical test that computes a p-value by re-shuffling the observed data many times under the null hypothesis and asking how…
- Representative Sampling (Representative Page Sampling)
- In web accessibility auditing, the practice of selecting a subset of pages from a website that statistically reflects the full site, so that evaluation findings can be generalised to pages not directl…
- Shannon Entropy (Information Entropy, Source Entropy)
- A measure of the average uncertainty or unpredictability associated with a set of possible outcomes, defined by Claude Shannon as H = -Σ p(x) log₂ p(x), where p(x) is the probability of each outcome. …
- Statistical Graph (Statistical Chart, Data Graph, Quantitative Graph)
- A visual representation of numerical or statistical data using geometric elements such as lines, bars, points, or areas to convey patterns, trends, relationships, and comparisons. Common types include…
- Stratified Sampling (Stratified Random Sampling)
- Stratified sampling is a statistical technique that divides a population into non-overlapping subgroups (strata) that share some characteristic, then draws a random sample from each stratum. In access…
- Wilcoxon Signed-Rank Test (Wilcoxon Test)
- The Wilcoxon signed-rank test is a non-parametric alternative to the paired t-test, used to compare two related samples when the data are ordinal or not normally distributed. It ranks the absolute dif…