ASQ - Six Sigma Forum



1.5 -sigma shifts and drifts: The theory that over time any process in control will shift from its target by a value of up to 1.5 sigma. Allowing for the 1.5 sigma shift results in the generally accepted six sigma value of 3.4 defects per million opportunities. Ignoring the 1.5 sigma shift results in a six sigma value of 2 defects per billion opportunities.

Academic Quality Improvement Project (AQIP): A forum for institutions to review each other's action projects.

Acceptable quality level (AQL): In a continuing series of lots, a quality level that, for the purpose of sampling inspection, is the limit of satisfactory process average.

Acceptance number: The maximum number of defects or defectives allowable in a sampling lot for the lot to be acceptable.

Acceptance sampling: Inspection of a sample from a lot to decide whether to accept that lot. There are two types: attributes sampling and variables sampling. In attributes sampling, the presence or absence of a characteristic is noted in each of the units inspected. In variables sampling, the numerical magnitude of a characteristic is measured and recorded for each inspected unit; this involves reference to a continuous scale of some kind.

Acceptance sampling plan: A specific plan that indicates the sampling sizes and associated acceptance or nonacceptance criteria to be used. In attributes sampling, for example, there are single, double, multiple, sequential, chain and skip-lot sampling plans. In variables sampling, there are single, double and sequential sampling plans. (For detailed descriptions of these plans, see the standard ANSI/ISO/ASQ A3534-2, Statistics—Vocabulary and Symbols—Statistical Quality Control.)

Accreditation: Certification by a duly recognized body of the facilities, capability, objectivity, competence and integrity of an agency, service, or operational group or individual to provide the specific service or operation needed.

Accuracy: The characteristic of a measurement that tells how close an observed value is to a true value.

Action plan: A specific method or process to achieve the results called for by one or more objectives. May be a simpler version of a project plan.

Active data gathering: A method for gathering data that involves approaching respondents to get information.

Actively solicited customer feedback: Proactive methods for obtaining customer feedback such as calling customers on the telephone or inviting customers to participate in focus groups.

Activity network diagram: An arrow diagram used in planning and managing processes and projects.

Advanced Product Quality Planning (APQP): Segment of QS-9000 process that uses tools to offer the opportunity to get ahead of problems and solve them before the problems affect the customer.

Aesthetics: A dimension of quality that refers to subjective sensory characteristics such as taste, sound, look, and smell.

Affinity diagram: A management tool used to organize information (usually gathered during a brainstorming activity).

Alignment: The actions taken to ensure a process or activity supports the organization's strategy, goals and objectives.

American Association for Laboratory Accreditation (A2LA): An organization that formally recognizes another organization's competency to perform specific tests, types of tests or calibrations.

American Customer Satisfaction Index (ACSI): Released for the first time in October 1994, an economic indicator and cross industry measure of the satisfaction of U.S. household customers with the quality of the goods and services available to them—both those goods and services produced within the United States and those provided as imports from foreign firms that have substantial market shares or dollar sales. The ACSI is co-sponsored by the University of Michigan Business School, ASQ and the CFI Group.

American National Standards Institute (ANSI): ANSI is a private, nonprofit organization that administers and coordinates the U.S. voluntary standardization and conformity assessment system. It is the United States' member body in the International Organization for Standardization, known as ISO.

American Society for Nondestructive Testing (ASNT): The world's largest technical society for nondestructive testing (NDT) professionals.

American Society for Quality (ASQ): A professional, not-for-profit association that develops, promotes and applies quality related information and technology for the private sector, government and academia. The Society serves more than 108,000 individuals and 1,100 corporate members in the United States and 108 other countries.

American Society for Quality Control (ASQC): Name of the Society from 1946 through the middle of 1997; then changed to ASQ.

American Society for Testing and Materials (ASTM): Not-for-profit organization that provides a forum for the development and publication of voluntary consensus standards for materials, products, systems and services.

American Society for Training and Development (ASTD): A membership organization providing materials, education and support related to workplace learning and performance.

American standard code for information interchange (ASCII): Basic computer characters accepted by all American machines and many foreign ones.

Analysis of means (ANOM): A statistical procedure for troubleshooting industrial processes and analyzing the results of experimental designs with factors at fixed levels. It provides a graphical display of data. Ellis R. Ott developed the procedure in 1967 because he observed that nonstatisticians had difficulty understanding analysis of variance. Analysis of means is easier for quality practitioners to use because it is an extension of the control chart. In 1973, Edward G. Schilling further extended the concept, enabling analysis of means to be used with non-normal distributions and attributes data where the normal approximation to the binomial distribution does not apply. This is referred to as analysis of means for treatment effects.

Analysis of variance (ANOVA): A basic statistical technique for analyzing experimental data. It subdivides the total variation of a data set into meaningful component parts associated with specific sources of variation in order to test a hypothesis on the parameters of the model or to estimate variance components. There are three models: fixed, random and mixed.

Anderson-Darling test for normality: P-value<0.05= not normal, normal=P-value>0.05

Annuity relationship: This occurs when a business receives many repeat purchases from a customer. The income is received steadily over time from a single customer.

Appraisal cost: The cost involved in ensuring an organization is continually striving to conform to customers' quality requirements.

Arrow diagram: A planning tool to diagram a sequence of events or activities (nodes) and the interconnectivity of such nodes. It is used for scheduling and especially for determining the critical path through nodes.

AS9100: An international quality management standard for the aerospace industry published by the Society of Automotive Engineers; also published by other organizations worldwide, as EN9100 in Europe and JIS Q 9100 in Japan. The standard is controlled by the International Aerospace Quality Group (see listing).

Assessment: A systematic process of collecting and analyzing data to determine the current, historical or projected status of an organization.

Assignable cause: A name for the source of variation in a process that is not due to chance and therefore can be identified and eliminated. Also called "special cause."

Association for Quality and Participation (AQP): Affiliate organization of the American Society for Quality (ASQ) dedicated to improving workplaces through quality and participation practices.

Assurance: A dimension of service quality that refers to the knowledge and courtesy of employees and their ability to inspire trust and confidence.

Attribute data: Go/no-go information. The control charts based on attribute data include percent chart, number of affected units chart, count chart, count per unit chart, quality score chart and demerit chart.

Attributes, method of: Measurement of quality by the method of attributes consists of noting the presence (or absence) of some characteristic (attribute) in each of the units under consideration and counting how many units do (or do not) possess it. Example: go/no-go gauging of a dimension.

Audit: The inspection and examination of a process or quality system to ensure compliance to requirements. An audit can apply to an entire organization or may be specific to a function, process or production step.

Automotive Industry Action Group (AIAG): The originator and sole source of the QS-9000 series of standards. ASQ's Automotive Division maintains a liaison to this group.

Availability: The ability of a product to be in a state to perform its designated function under stated conditions at a given time.

Average chart: A control chart in which the subgroup average, X-bar, is used to evaluate the stability of the process level.

Average outgoing quality (AOQ): The expected average quality level of outgoing product for a given value of incoming product quality.

Average outgoing quality limit (AOQL): The maximum average outgoing quality over all possible levels of incoming quality for a given acceptance sampling plan and disposal specification.

Average run lengths (ARL): On a control chart, the number of subgroups expected to be inspected before a shift in magnitude takes place.

Average sample number (ASN): The average number of sample units inspected per lot in reaching decisions to accept or reject.

Average total inspection (ATI): The average number of units inspected per lot, including all units in rejected lots (applicable when the procedure calls for 100% inspection of rejected lots).


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