Statistical Process Control & Quality Management

← Back to Domain-Specific Families

Abstractions about monitoring and improving process quality through statistics and structured methods, including control charts for detecting process variation (X-bar chart, U-chart, regression control chart), capability and performance metrics (process capability index, process performance index, critical to quality), and quality-improvement frameworks (Capability Maturity Model, quality function deployment, quality storyboard).

15 abstractions in this family — domain-specific abstractions that sit near one another in structural-signature space (k-means over structural-signature embeddings). Each is shown with its short description.

• Analytic and enumerative statistical studies — Deming’s distinction between studies estimating a defined finite population and studies learning how a continuing process will behave under future conditions.
• Capability Maturity Model — A staged process-improvement model that assesses organizational software practice from ad hoc execution through defined, measured and continuously optimizing control.
• Conformance testing — Assessment of whether a product, process, service, or implementation satisfies stated requirements of a specification, standard, contract, or regulation.
• Critical to quality — A measurable product, service or process characteristic whose performance has a direct and substantial effect on customer-perceived or required quality.
• Distribution-free control chart — A statistical process-monitoring chart whose in-control performance does not depend on a specified underlying process distribution.
• Process capability index — A family of ratios comparing a statistically stable process’s natural variation and centering with engineering specification limits.
• Process performance index — A ratio comparing the nearest specification limit to three estimated long-term standard deviations from the observed process mean, commonly denoted Ppk.
• Process validation — A lifecycle program of evidence demonstrating that a defined process can consistently produce outputs meeting predetermined requirements.
• Quality function deployment — A structured method for translating customer needs into prioritized technical characteristics and cascading them through product or service design.
• Quality storyboard — A visual sequence that records a quality-improvement problem, evidence, analysis, interventions and results in the order of a structured improvement cycle.
• Regression control chart — A statistical process-control chart monitoring deviations from an expected regression relation when the process mean legitimately varies with one or more covariates.
• Software quality assurance — Planned process-level activities that establish, monitor and audit standards, methods and evidence so software work products and engineering practices meet defined quality requirements.
• Tampering (quality control) — Adjustment of a stable process in response to ordinary common-cause variation, thereby increasing rather than reducing output variability.
• U-chart — A statistical process-control chart for nonconformities per inspection unit when the number or size of units inspected can vary between samples.
• X-bar chart — A variables control chart that plots successive subgroup means against a center line and statistically derived limits to monitor shifts in a process mean.