P chart (percent chart)

A P chart, or percent chart, is a type of control chart used in quality control to monitor the proportion of defective items or nonconforming units in a process. It displays the percentage of defects in samples over time, making it suitable for attribute data that follow a binomial distribution.
See also: Control Chart, Attribute Data

PDCA cycle (Plan-Do-Check-Act)

The PDCA cycle is a continuous improvement framework that consists of four iterative steps: Plan, Do, Check, and Act. It is used to test changes, monitor results, and implement process improvements systematically.
See also: Continuous Improvement, Deming Cycle

PDPC (Process Decision Program Chart)

A Process Decision Program Chart (PDPC) is a planning tool that maps out potential problems and decision points within a process. It helps in anticipating risks and developing contingency plans to manage possible issues effectively.
See also: Risk Management, Contingency Planning

PEST analysis

PEST analysis is a strategic tool used to examine the external macro-environmental factors affecting an organization. It focuses on Political, Economic, Social, and Technological factors to provide insights into external influences on business strategy.
See also: SWOT Analysis, Environmental Scanning

Pareto analysis

Pareto analysis is a decision-making technique based on the principle that a small number of causes (roughly 20%) are often responsible for a large portion (about 80%) of problems. This method helps prioritize issues by addressing the most significant contributors first.
See also: Pareto Principle, Root Cause Analysis

Pareto chart

A Pareto chart is a graphical tool that displays factors in descending order of significance as bars, alongside a cumulative percentage line. It visualizes which issues or causes have the greatest impact, facilitating targeted improvements.
See also: Pareto Analysis, 80/20 Rule

Pareto principle (80/20 rule)

The Pareto principle, or the 80/20 rule, posits that approximately 80% of effects stem from 20% of the causes. This observation is commonly used in business and quality improvement to focus efforts on the most influential factors.
See also: Pareto Analysis, Prioritization

Parts per million (PPM)

Parts per million (PPM) is a unit of measurement indicating the number of defective parts in a million produced. It is commonly used in quality control to express defect rates or the concentration of impurities.
See also: Quality Metrics, Defect Rate

Performance

Performance refers to the effectiveness and efficiency with which an individual, process, or system achieves its intended objectives. It encompasses aspects such as productivity, quality, and timeliness.
See also: Productivity, Efficiency

Performance measurement

Performance measurement involves the systematic collection and analysis of data to evaluate how well an organization, process, or individual is achieving predetermined objectives. This process typically utilizes Key Performance Indicators (KPIs) and other benchmarks.
See also: KPIs, Benchmarking

Poka-yoke

Poka-yoke is a lean manufacturing technique aimed at mistake-proofing a process. It involves designing mechanisms or procedures that either prevent errors or make them immediately obvious, thus reducing defects and ensuring quality.
See also: Error-Proofing, Quality Control

Poisson distribution

The Poisson distribution is a discrete probability distribution that describes the likelihood of a given number of events occurring in a fixed interval of time or space, based on a known average rate and assuming events occur independently.
See also: Exponential Distribution, Probability Models

Population

In statistics, a population is the complete set of items, events, or individuals that share a common characteristic and from which a sample may be drawn for analysis.
See also: Sample, Statistical Inference

Power (statistical power)

Statistical power is the probability that a hypothesis test will correctly reject a false null hypothesis. It reflects the test's ability to detect an effect if one truly exists, thereby reducing the risk of a Type II error.
See also: Type II Error, Effect Size

Precision

Precision refers to the consistency or repeatability of measurements or results. It describes how closely multiple measurements of the same variable agree with each other, independent of their accuracy relative to the true value.
See also: Accuracy, Measurement Reliability

Pre-control chart

A pre-control chart is a straightforward tool used to monitor process stability and quickly determine if a process remains within acceptable limits. It serves as an early warning system indicating when adjustments may be needed before more comprehensive control charts are employed.
See also: Control Charts, Process Stability

Predictive maintenance

Predictive maintenance is a proactive approach that uses data analysis and condition-monitoring tools to predict equipment failures before they happen. This strategy enables timely maintenance actions, reducing unexpected downtime and optimizing equipment performance.
See also: Preventive Maintenance, Condition-based Maintenance

Preventive action

Preventive action involves proactive steps taken to eliminate the causes of potential nonconformities or issues before they occur. Its goal is to improve processes and mitigate risks by addressing root causes rather than reacting to problems after they manifest.
See also: Root Cause Analysis, Corrective Action

Preventive maintenance

Preventive maintenance consists of planned, routine maintenance tasks aimed at keeping equipment in optimal working condition. This approach helps prevent breakdowns, extends equipment life, and supports uninterrupted production.
See also: Predictive Maintenance, Scheduled Maintenance

Probability

Probability is a numerical measure of the likelihood that a particular event will occur, expressed as a value between 0 and 1. It forms the basis for statistical inference and risk assessment.
See also: Statistics, Likelihood

Probability of acceptance

The probability of acceptance is the likelihood that a batch or lot will be accepted under a specified sampling plan, given its level of quality or defect rate. It is a key concept in acceptance sampling used to balance risks between producers and consumers.
See also: Operating Characteristic Curve, Acceptance Sampling

Probability of rejection

The probability of rejection represents the likelihood that a batch or lot will be rejected under a sampling plan, based on the observed quality or defect rate. This measure assists in assessing the risk of releasing substandard products.
See also: Operating Characteristic Curve, Acceptance Sampling

Process

A process is a sequence of interrelated activities or steps that converts inputs (such as materials, information, or energy) into outputs (products or services). Processes are fundamental to operations management and are often analyzed for efficiency and effectiveness.
See also: Workflow, Business Process Management

Process average

The process average is the mean value derived from measurements of a process output. It represents the central tendency of the process data and is useful for monitoring performance and identifying trends over time.
See also: Mean, Central Tendency

Process capability (Cp)

Process capability (Cp) is an index that quantifies a process's ability to produce output within specified limits. It compares the spread of process variation with the width of the specification limits, indicating the potential performance of the process.
See also: Process Capability Index (Cpk), Six Sigma

Process capability index (Cpk)

The process capability index (Cpk) is a statistical measure that evaluates how close a process is running to its specification limits while considering its variability. It provides insight into the actual performance of a process in producing quality output consistently.
See also: Process Capability (Cp), Six Sigma

Process control

Process control is a method for continuously monitoring and adjusting process variables to ensure that a system produces products or outputs within desired specifications. It helps maintain consistency in quality and performance over time.
See also: Statistical Process Control (SPC), Control Charts

Process decision program chart (PDPC)

A process decision program chart (PDPC) is a planning tool that maps out potential issues, decision points, and countermeasures in a process. It assists in anticipating problems and developing contingency plans for smoother operations.
See also: Risk Management, Contingency Planning

Process flowchart

A process flowchart is a visual diagram that outlines the sequential steps, decision points, and interactions within a process. It simplifies complex processes and aids in analysis, communication, and improvement initiatives.
See also: Process Mapping, Workflow Diagram

Process improvement

Process improvement is the systematic approach to analyzing and enhancing existing processes to boost efficiency, reduce waste, and increase quality. It often employs methodologies such as Six Sigma, Lean, or Kaizen.
See also: Continuous Improvement, Lean Manufacturing

Process kaizen

Process kaizen is an ongoing, incremental approach to improving a process by making small, continuous changes. Rooted in Japanese management philosophy, it encourages employee involvement and iterative enhancements.
See also: Continuous Improvement, Lean, Process Improvement

Process mapping

Process mapping involves creating a detailed visual representation of a process’s steps, inputs, outputs, and interactions. It supports clearer understanding, identification of bottlenecks, and targeted process refinement.
See also: Process Flowchart, Value Stream Mapping

Process owner

A process owner is the individual responsible for the overall performance, management, and continual improvement of a specific process. They ensure that the process meets organizational objectives and quality standards.
See also: Process Management, Process Improvement

Process performance

Process performance describes how effectively a process operates, typically measured using indicators such as cycle time, throughput, quality, and cost. Monitoring process performance is essential for identifying areas for improvement.
See also: Key Performance Indicators (KPIs), Process Optimization

Process sigma

Process sigma is a metric derived from Six Sigma methodology that quantifies a process's capability to produce defect-free output. It measures the spread of process variation relative to specification limits.
See also: Six Sigma, Process Capability (Cpk)

Process stability

Process stability refers to the consistency of a process in producing predictable results over time, with minimal variability when external conditions remain constant.
See also: Statistical Process Control (SPC), Process Control

Proctor test (soil compaction)

The Proctor test is a standardized laboratory procedure used in geotechnical engineering to determine the optimal moisture content and maximum dry density of soil. It ensures that soil compaction meets engineering requirements for construction projects.
See also: Soil Compaction, Geotechnical Testing

Producer’s risk (α risk)

Producer’s risk (α risk) is the probability of rejecting a lot or batch that actually meets the quality standards during acceptance sampling. It represents the risk borne by the producer when a defect-free batch is mistakenly discarded.
See also: Type I Error, Acceptance Sampling

Producer’s risk (alpha)

Producer’s risk (alpha) is synonymous with the α risk; it quantifies the chance of erroneously rejecting an acceptable lot in quality control sampling.
See also: Type I Error, Acceptance Sampling

Procedure

A procedure is a set of detailed, sequential instructions designed to accomplish a specific task. It ensures that tasks are performed consistently and accurately, adhering to established standards or regulations.
See also: Standard Operating Procedure (SOP), Work Instructions

Product audit

A product audit is a systematic review and evaluation of a product to ensure it meets predefined quality, safety, and performance requirements. This process helps identify defects and verify compliance with standards.
See also: Quality Audit, Inspection

Product quality

Product quality is the degree to which a product meets or exceeds customer expectations and regulatory standards. It encompasses characteristics such as performance, durability, reliability, and aesthetics.
See also: Quality Assurance, Quality Control

Production part approval process (PPAP)

The Production Part Approval Process (PPAP) is a standardized method used in manufacturing—particularly in the automotive and aerospace industries—to confirm that a supplier’s production process can reliably produce parts that meet all specifications and quality standards.
See also: Supplier Quality Management, Quality Assurance

Productivity

Productivity measures the efficiency of production, defined as the ratio of outputs produced to the inputs utilized. It is a key indicator of operational performance and resource utilization.
See also: Efficiency, Output

Project charter

A project charter is a formal document that authorizes the start of a project by outlining its objectives, scope, key stakeholders, and the authority of the project manager. It serves as a framework and point of reference throughout the project lifecycle.
See also: Project Management, Scope Statement

Project management

Project management is the discipline of organizing, planning, and executing projects to achieve specific goals within defined constraints such as time, cost, and scope. It encompasses initiation, planning, execution, monitoring, and closure phases.
See also: Project Planning, Risk Management

Project planning

Project planning is the process of defining project objectives, tasks, timelines, resources, and milestones to create a comprehensive roadmap for successful project execution. It is fundamental to achieving project goals efficiently.
See also: Project Management, Gantt Chart

Proportion chart (p-chart)

A proportion chart (p-chart) is a type of control chart used in quality control to monitor the proportion of defective or nonconforming items in a sample. It is particularly useful for tracking attribute data to identify trends and shifts in process quality.
See also: Control Charts, Attribute Data