1.0 Data Quality Ontology Based on the IQ Qurator model defined in the paper "Quality Views: capturing and exploiting the user perspective on data quality" by P. Missier, S. Embury, M. Greenwood, A. Preece, and B. Jin. A quality assertion function is used to describe how a quality expression is determined from available quality evidence for a given quality aspect. Quality assertion function Representativeness A quality aspect is a simple representation of a characteristic of a data entity that affects fitness-for-use. Examples include completeness, consistency, accuracy, representativeness, bias, etc. Quality aspect Consistency A quality indicator is a property that can be computed or estimated to provide evidence for a quality assertion. The slope of a trend-line from a comparison of truth vs estimated values can be a quality indicator for bias. The computed value of the trend-line slope (quality evidence) can be used to make a assertion about bias for the data entity. Quality indicator A Data entity defines the scope of the scope of the data for which evidence has been computed and assertions are held to be valid. A data entity can be described for a wide range of granularity, from representing collections to granules and a data entity may represent a subset based on criteria (e.g. region, season, thresholds) specified for the domain. Data entity Intuitive and ready-to-use expressions of quality (e.g. bad, marginal, good, very good) Quality expression Function Data plot Correctness Currency Quality evidence is the quantification of a quality indicator for some data entity. Quality evidence Accuracy A quality assertion is an event whereby a quality expression for some quality aspect is asserted for a data entity based on quality evidence computed from that data entity. A quality assertion may reference a function to describe how assertion expressions are decided based on quality evidence. For example, based on the slope of a linear-regression fit (indicator) of 1.3 (evidence), a data product (data entity) may be asserted to have a bias (quality aspect) overestimation of 30% (bias-specific quality expression). Quality assertion 1 Data figure A quality evidence function is used to describe how quality evidence is computed from a data entity for a quality indicator. Quality evidence function Reputation Completeness Data representation has representation evidence of indicator assertion of quality expression evidence for data entity evidence for assertion has measure assertion about dimension evidence for quality property described by quality assertion described by quality evidence assertion for data entity indicator for quality property assertion based on evidence computed by function value