====== Quality Characteristic ====== [[dido:99_annexes:annex-b-terms-and-definitions:start|Go up to Terms and Definitions]] ===== Discussion ===== A Quality Characteristic is an [[dido:99_annexes:annex-b-terms-and-definitions:e:evaluation_characteristic|Evaluation Characteristic]] concerning the degree to which a subject exhibits a quality property. A Quality Characteristic can apply to: * A [[dido:99_annexes:annex-b-terms-and-definitions:c:candidate_solution|Candidate Solution]] * A [[dido:99_annexes:annex-b-terms-and-definitions:d:distributed_system|Distributed System]] * A [[dido:99_annexes:annex-b-terms-and-definitions:n:node|Node]] * A [[dido:99_annexes:annex-b-terms-and-definitions:n:node_set|Node Set]] * A [[dido:99_annexes:annex-b-terms-and-definitions:t:test_item|Test Item]] * A software product * A hardware product * A service * A technology * A process * A result * Another evaluation subject Quality Characteristics can include: * Functional Correctness * Performance Efficiency * Reliability * Operational Stability * Security * Interoperability * Scalability * Maintainability * Recoverability A Quality Characteristic can be decomposed into more specific Quality Characteristics or quality subcharacteristics. A Quality Characteristic can identify: * Its identity * Its name * Its description * Its parent Quality Characteristic * Its child Quality Characteristics * Its evaluation subject * Its applicable context * Its applicable measures * Its applicable measurement methods * Its applicable measurement units * Its applicable reference values * Its applicable DIDO [[dido:99_annexes:annex-b-terms-and-definitions:b:baseline|Baselines]] * Its applicable [[dido:99_annexes:annex-b-terms-and-definitions:v:validation_criteria|Validation Criteria]] * Its applicable [[dido:99_annexes:annex-b-terms-and-definitions:a:acceptance_criteria|Acceptance Criteria]] * Its applicable [[dido:99_annexes:annex-b-terms-and-definitions:g:governance_policy|Governance Policies]] * Its [[dido:99_annexes:annex-b-terms-and-definitions:e:evidence|Evidence]] * Its [[dido:99_annexes:annex-b-terms-and-definitions:p:provenance|Provenance]] * Its [[dido:99_annexes:annex-b-terms-and-definitions:t:traceability|Traceability]] ===== Definition ===== //[[dido:99_annexes:annex-b-terms-and-definitions:e:evaluation_characteristic|Evaluation Characteristic]] concerning the degree to which a subject exhibits a quality property// ===== Source ===== Adapted from: * [[https://www.iso.org/standard/78176.html|ISO/IEC 25010:2023, Systems and software Quality Requirements and Evaluation (SQuaRE) — Product quality model]] * [[https://www.iso.org/standard/78175.html|ISO/IEC 25002:2024, Systems and software Quality Requirements and Evaluation (SQuaRE) — Quality model overview and usage]] * [[dido:99_annexes:annex-b-terms-and-definitions:e:evaluation_characteristic|Evaluation Characteristic]] * DIDO Reference Implementation Conceptual Model * DIDO-TE draft Requirements Register ISO/IEC 25002 describes quality models composed of quality characteristics and subcharacteristics. ISO/IEC 25010 defines a product-quality model containing characteristics and subcharacteristics applicable to ICT and software products. This definition places Quality Characteristic within the broader DIDO Evaluation Characteristic model so DIDO-TE can evaluate both quality properties and non-quality characteristics such as cost and resource consumption. ===== Note ===== Every Quality Characteristic is an Evaluation Characteristic. An Evaluation Characteristic is not necessarily a Quality Characteristic. A Quality Characteristic differs from a measure: * A Quality Characteristic identifies the quality property subject to evaluation * A measure identifies how a value is assigned to the Quality Characteristic A Quality Characteristic differs from a quality requirement: * A Quality Characteristic identifies a quality property * A quality requirement establishes a normative obligation concerning that quality property A Quality Characteristic differs from a [[dido:99_annexes:annex-b-terms-and-definitions:t:test_result|Test Result]]: * A Quality Characteristic identifies what is evaluated * A Test Result records an outcome produced by [[dido:99_annexes:annex-b-terms-and-definitions:t:test_execution|Test Execution]] One Test Result can provide information about multiple Quality Characteristics. Multiple Test Results can contribute to the evaluation of one Quality Characteristic. A Quality Characteristic does not by itself establish: * A required value * A minimum value * A maximum value * A preferred direction * A measurement method * A permitted tolerance * An acceptance threshold The applicable Acceptance Criteria or Validation Criteria establish those constraints. A higher numerical value does not necessarily indicate better quality. The interpretation depends on the Quality Characteristic and its applicable measure. For example: * Higher throughput can indicate greater Performance Efficiency * Higher response time can indicate lower Performance Efficiency * Higher failure frequency can indicate lower Reliability * Higher recovery success can indicate greater Recoverability ===== Example ===== A DIDO-TE comparative evaluation selects Reliability as a Quality Characteristic. The applicable Acceptance Criteria establish: * The Candidate Solutions subject to evaluation * The workload * The Test Environment * The duration of the evaluation * The failure conditions * The Reliability measures * The required measurement precision * The comparison method DIDO-TE produces Test Results used to evaluate Reliability for each Candidate Solution. Reliability identifies the quality property being evaluated. The Test Results contain the observations and measurements used to evaluate it. ---- © 2026 Dido Solutions, Inc. and Jackrabbit Consulting, Inc.