Testing to ensure that product conforms to defined user needs and/or requirements. Design validation follows successful design verification and is normally performed on the final product under defined, operating conditions. Multiple validations may be performed if there are different intended uses

Testing to ensure that all design outputs meet design input requirements. Design verification may include activities such as: Design Review, Performing Alternate Calculations, Understanding Tests & Demonstrations and Review of Design Stage Documents Before Release

A systematic approach to software creation that defines development phases and specifies the activities, products, verification procedures, and completion criteria for each phase. See: incremental development, rapid prototyping, spiral model, waterfall model

Design Failure Mode Effects Analysis: An analytical technique used to assure that potential design failure modes and associated causes have been considered and addressed. [See FMEA, PFMEA] 

Pertaining to the detection and isolation of faults or failures. For example, a diagnostic message, a diagnostic manual

A method of performing an economic analysis that takes the time value of money into account. Used to remove interest rates and inflation factors from a calculation so that the results of analysis are comparable

Tendency of large numbers of observations to group themselves around some central value with a certain amount of variation or "scatter" on either side 

Plans for acceptance sampling developed by Harold F. Dodge and Harry G. Romig. Four sets of tables were published in 1940: single-sampling lot tolerance tables, double-sampling lot tolerance tables, single-sampling average outgoing quality limit tables, and double-sampling average outgoing quality limit tables

DOE is the science of designing sets of experiments which will generate enough useful data to make sound decisions without costing too much or taking too long

The probability that an item will continue to function at customer expectation levels, at the useful life without requiring overhaul or rebuild due to wear out

Analysis that is performed by executing the program code. Contrast with static analysis. See: testing

A formal method of comparing two or more alternative ways of accomplishing a set objective, given a set of assumptions and constraints and the costs and benefits of each alternative, such that the analysis will indicate the optimum choice

The state of having produced a decided or desired effect; the state of achieving customer satisfaction 

Software that is part of a larger system and performs some of the requirements of that system; e,g., software used in an aircraft or rapid transit system. Such software does not provide an interface with the user. See: firmware

Regular participation of employees in decision-making and suggestions. The driving forces behind increasing the involvement of employees are the conviction that more brains are better, that people in the process know it best, and that involved employees will be more motivated to do what is best for the organization

(1) A person, device, program, or computer system that uses an information system for the purpose of data processing in information exchange. (2) A person whose occupation requires the use of an information system but does not require any knowledge of computers or computer programming. See: user

The representation of a set of real or abstract things (people, objects, places, events, ideas, combination of things, etc.) that are recognized as the same type because they share the same characteristics and can participate in the same relationships

A diagram that depicts a set of real-world entities and the logical relationships among them. See: data structure diagram

(1) Everything that supports a system or the performance of a function. (2) The conditions that affect the performance of a system or function

Partitioning the input domain of a program into a finite number of classes [sets], to identify a minimal set of well selected test cases to represent these classes. There are two types of input equivalence classes, valid and invalid

A discrepancy between a computed, observed, or measured value or condition and the true, specified, or theoretically correct value or condition. See: anomaly, bug, defect, exception, fault

Techniques used to identify errors in data transfers. See: check summation, cyclic redundancy check [CRC], parity check, longitudinal redundancy

The process of intentionally adding known faults to those already in a computer program for the purpose of monitoring the rate of detection and removal, and estimating the number of faults remaining in the program. Contrast with mutation analysis

A happening, the arrival of a significant point in time, a change in status of something or the occurrence of something external that causes the business to react

An event that causes suspension of normal program execution. Types include addressing exception, data exception, operation exception, overflow exception, protection exception, underflow exception

A record of the sequence of instructions executed during the execution of a computer program. Often takes the form of a list of code labels encountered as the program executes. Syn: code trace, control flow trace. See: retrospective trace, subroutine trace, symbolic trace, variable trace

Customer perceptions about how a product or service will meet their needs and requirements; expectations for a product or service are shaped by many factors; including the specific use the customer intends to make of it, prior experience with a similar product or service and representations and commitments made by marketing and advertising

A test under defined conditions to determine an unknown effect; to illustrate or verify a known law; to test or establish a hypothesis

A formal plan that details the specifics for conducting an experiment, such as which responses, factors, levels, blocks, treatments, and tools are to be used

Variation in observations made under identical test conditions. Also called residual error. The amount of variation which cannot be attributed to the variables included in the experiment

A person or organization outside your organization who receives the output of a process. Of all external customers, the end-user should be the most important

Test data that is at the extreme or boundary of the domain of an input variable or which produces results at the boundary of an output domain

Person who helps a team with issues of teamwork, communication, and problem-solving. A facilitator should not contribute to the actual content of the team's project, focusing instead as an observer of the team's functioning as a group