Selecting a sample so each item in the population has an equal chance of being selected; lack of predictability; without pattern

A source of variation which is random; a change in the source ("trivial many" variables) will not produce a highly predictable change in the response (dependent variable), e.g., a correlation does not exist; any individual source of variation results in a small amount of variation in the response; cannot be economically eliminated from a process; an inherent natural source of variation

Experimental treatments are a random sample from a larger population of treatments. Conclusions can be extended to the population. Interference's are not restricted to the experimental levels

The process of selecting units for a sample of size, so that all units have an equal chance of being selected as the sample / Or / A commonly used sampling technique in which sample units are selected in such a manner that all combinations of n units under consideration have an equal chance of being selected as the sample

A condition in which any individual event in a set of events has the same mathematical probability of occurrence as all other events within the specified set, i.e., individual events are not predictable even though they may collectively belong to a definable distribution

Control chart in which the range of the subgroup is used to track the instantaneous variation within a process, i.e. the variation in the process at any one time, when many input factors would not have time to vary enough to make a detectable difference. Range charts are usually paired with average charts for complete analysis

A structured software requirements discovery technique which emphasizes generating prototypes early in the development process to permit early feedback and analysis in support of the development process. Contrast with incremental development, spiral model, waterfall model. See: prototyping

Numeric scale which has an absolute zero point and equal units of measure throughout, i.e., measurements of an output parameter, i.e., amps

A fast-response [immediate response] on-line system which obtains data from an activity or a physical process, performs computations. and returns a response rapidly enough to affect [control] the outcome of the activity or process; ~g., a process control application. Contrast with batch processing

(1) (ISO) a group of related data elements treated as a unit. [A data element (field) is a component of a record, a record is a component of a file (database)]

Documentation of changes made to the system. A record of change can be a written document or a database. Normally there are two associated with a computer system, hardware and software. Changes made to the data are recorded in an audit trail

The team member that takes minutes during team meetings to capture team's progress. Once the team is well underway, this role can be rotated through out the group

An experiment developed by W. Edwards Deming to illustrate that it is impossible to put employees in rank order of performance for the coming year based on their performance during the past year because performance differences must be attributed to the system, not to employees. Four thousand red and white beads, 20% red, in a jar and six people are needed for the experiment. The participants goal is to produce white beads, because the customer will not accept red beads. One person begins by stirring the beads and then, blindfolded, selects a sample of 50 beads. That person hands the jar to the next person, who repeats the process, and so on. When everyone has his or her sample, the number of red beads for each is counted. The limits of variation between employees that can be attributed to the system are calculated. Everyone will fall within the calculated limits of variation that could arise from the system. The calculations will show that there is no evidence one person will be a better

The transformation of a business process to achieve significant levels of improvement in one or more performance measures relating to fitness for purpose, quality, cycle times, and cost by using the techniques of streamlining and removing non value added activities and costs

Registered Suppliers are suppliers who have received third party registration to a specific quality system standard for the commodity supplied

A board that evaluates the competency and reliability of registrars (organizations that assess and register companies to the appropriate ISO 9000 series standards). The Registrar Accreditation Board, formed in 1989 by ASQ, is governed by a board of directors from industry, academia, and quality management consulting firms

A process in which an accredited, independent third-party organization conducts an on-site audit of a company’s operations against the requirements of the standard to which the company wants to be registered. Upon successful completion of the audit, the company receives a certificate indicating that it has met the standard requirements

Action taken on non-conforming product that changes the classification, or category of the product for use in alternative applications. Cannot be done without customer approval/direction. [Also see Repair/Rework] 

A statistical technique used to determine the best mathematical expression to describe the relationship between a response and independent variables

A software V&V task to determine the extent of V&V analysis and testing that must be repeated when changes are made to any previously examined software products. See: testing, regression

A group formed by individuals or work groups to address problems keeping them from a defect free standard or to spawn continuous work process improvements

Database organization method that links files together as required. Relationships between files are created by comparing data such as account numbers and names. A relational system can take any two or more files and generate a new file from the records that meet the matching criteria. Routine queries often involve more than one data file; e.g., a customer tile and an order file can be linked in order to ask a question that relates to information in both tiles, such as the names of the customers that purchased a particular product. Contrast with network database, flat tile

Method is a technique developed to clarify intertwined causal relationships in a complex situation in order to find an appropriate solution. It is typically represented graphically as squared ellipses (concepts) connected by directed lines (arrowheads show direction). The directed lines represent causal relations between the concepts

The probability that an item will continue to function at customer expectation levels at a measurement point, under specified environmental and duty cycle conditions / Or / The ability of a system or component to perform its required functions under stated conditions for a specified period of time. See: software reliability / Or / the probability of a product performing its intended function under stated conditions without failure for a given period of time

The process of determining the achieved level of reliability for an existing system or system component

Taken on non-conforming product so that the product will fulfill the intended usage, although the product may not conform to the original requirements. [Also see Regrade/Rework] 

(1) A condition or capability needed by a user to solve a problem or achieve an objective (2) A condition or capability that must be met or possessed by a system or system component to satisfy a contract, standard. specification, or other formally imposed documents. (3) A documented representation of a condition or capability as in (1) or (2). See: design requirement, functional requirement, implementation requirement, interface requirement, performance requirement, physical requirement

(1) The process of studying user needs to arrive at a definition of a system, hardware, or software requirements. (2) The process of studying and refining system, hardware, or software requirements. See: prototyping, software engineering

The period of time in the software life cycle during which the requirements, such as functional and performance capabilities for a software product, are defined and documented

Critical and exhaustive investigation or experimentation having for its aim the revision of accepted conclusions in the light of newly discovered facts

Those items necessary for a team to understand a problem and implement solutions; also, the time to work on solutions, access to manufacturing engineers, etc

Relative to software changes, revalidation means validating the change itself, assessing the nature of the change to determine potential ripple effects, and performing the necessary regression testing

A process or meeting during which a work product or set of work products, is presented to project personnel, managers, users, customers, or other interested parties for comment or approval. Types include code review, design review, formal qualification review, requirements review, test readiness review. Contrast with audit, inspection. See: static analysis

A term used to convey the concept that it is beneficial and more cost-effective to take the necessary steps up front to ensure a product or service meets its requirements than to provide a product or service that will need rework or not meet customers needs. In other words, an organization should engage in defect prevention rather than defect detection

A measure of the probability and severity of undesired effects. Often taken as the simple product of probability and consequence