Hard data: Measurements data such as height, weight, volume, or speed that can be measured on a continuous scale.
Hawthorne effect: The concept that every change results (initially, at least) in increased productivity.
Hazard analysis and critical control point (HACCP): A quality management system for effectively and efficiently ensuring farm to table food safety in the United States. HACCP regulations for various sectors are established by the United States Department of Agriculture and the Food and Drug Administration.
Heijunka: The act of leveling the variety or volume of items produced at a process over a period of time. Used to avoid excessive batching of product types and volume fluctuations, especially at a pacemaker process.
Highly accelerated life test (HALT): A process developed to uncover design defects and weaknesses in electronic and mechanical assemblies using a vibration system combined with rapid high and low temperature changes. The purpose of HALT is to optimize product reliability by identifying the functional and destructive limits of a product. HALT addresses reliability issues at an early stage in product development.
Highly accelerated stress audits (HASA): A technique in which a sample of parts (as opposed to 100% of the production as in HASS, below) is taken and subjected to stresses similar to the levels and duration for HALT. In monitoring the production process, the intent of HASA is to detect slight shifts in the attributes of the product so corrective actions can be taken and implemented before the performance of outgoing product approaches the specifications.
Highly accelerated stress screening (HASS): A technique for production screening that rapidly exposes process or production flaws in products. Its purpose is to expose a product to optimized production screens without affecting product reliability. Unlike HALT, HASS uses nondestructive stresses of extreme temperatures and temperature change rates with vibration.
Histogram: A graphic summary of variation in a set of data. The pictorial nature of the histogram lets people see patterns that are difficult to detect in a simple table of numbers. The histogram is one of the "seven tools of quality."
Horizontal deployment: A term that denotes that all of the departments of a firm are involved in the firm's quality efforts.
Hoshin planning: Breakthrough planning. A Japanese strategic planning process in which a company develops up to four vision statements that indicate where the company should be in the next five years. Company goals and work plans are developed based on the vision statements. Periodic audits are then conducted to monitor progress.
House of quality: A product planning matrix, somewhat resembling a house, that is developed during quality function deployment and shows the relationship of customer requirements to the means of achieving these requirements.
Hunter, J. Stuart: An Honorary Member of ASQ, Hunter is a professor emeritus at Princeton University. His work as an educator and author helped enhance quantitative understanding. He wrote or co-wrote many papers, books and technical reports and is a founding editor of Technometrics.
Hypothesis testing (alpha error, beta error, t-test, F-test): Statistically determining whether two or more populations differ significantly or simply because of random chance. A null hypothesis that assumes no significant difference is accepted or rejected. If the null hypothesis is rejected, an alternative hypothesis that assumes a true difference is accepted.