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Geospatial Quality Council
Glossary
This Glossary is combined from the glossaries of EPA Manual 5360.1 A2, EPA/240/R-03/003, EPA/240/R-02/004, and EPA/240/R-02/007
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acceptance criteria – specific limits placed on an item, process, or service defined in requirements documents. Acceptance criteria are acceptable thresholds or goals for data, usually based on individual data quality indicators (precision, accuracy, representativeness, comparability, completeness, and sensitivity).
accuracy – the degree to which a calculation, measurement, or set of measurements agree with a true value or an accepted reference value. Accuracy includes a combination of random error (precision) and systematic error (bias) components which are due to sampling and analytical operations. A data quality indicator. EPA recommends that this term not be used and that precision and bias be used to convey the information usually associated with accuracy.
address geocoding – assigning x, y coordinates to tabular data such as street addresses.
assessment – the evaluation process used to measure the performance or effectiveness of a system and its elements. As used here, assessment is an all-inclusive term used to denote any of the following: audit, performance evaluation, management systems review, peer review, inspection, or surveillance.
attribute – any property, quality, or characteristic of sampling unit. The indicators and other measures used to characterize a sampling site or resource unit are representations of the attributes of that unit or site. A characteristic of a map feature (point, line, or polygon) described by numbers or text; for example, attributes of a tree represented by a point might include height and species. (See related: Continuous)
attribute accuracy – the closeness of attribute values (characteristic of the location) to their true value, which includes continuous attributes with measurement error (e.g., elevation) and categorical accuracy resulting from misclassification (e.g., soil types on a soil map).
audit (quality) – a systematic and independent examination to determine whether quality activities and related results comply with planned arrangements and whether these arrangements are implemented effectively and are suitable to achieve objectives.
band – one layer of a multispectral image that represents data values for a specific range of reflected light or heat—such as ultraviolet, blue, green, red, infrared, or radar—or other values derived by manipulating the original image bands.
bias – in a sampling context, the difference between the conceptual, weighted average value of an estimator over all possible samples and the true value of the quantity being estimated. An estimator is said to be unbiased if that difference is zero. The systematic or persistent distortion of a measurement process that deprives the result of representativeness (i.e., the expected sample measurement is different than the sample’s true value). A data quality indicator.
boundary condition – mathematical expression of a state of the environmental system that constrains the equations of the mathematical model
calibration – comparison of a measurement standard, instrument, or item with a standard or instrument of higher accuracy to detect and quantify inaccuracies and to report or eliminate those inaccuracies by adjustments.
cell size – the area on the ground covered by a single pixel in an image, measured in map units.
chain-of-custody – an unbroken trail of accountability that ensures the physical security of samples, data, and records.
classification – the process of assigning a resource unit to one of a set of classes defined by values of specified attributes. For example, forest sites will be classified into the designated forest types, depending on the species composition of the forest. Systematic arrangement of objects into groups or categories according to established criteria
comparability – the degree to which different methods, data sets, and/or decisions agree or can be represented as similar.
completeness – the amount of valid data obtained compared to the planned amount, usually expressed as a percentage.
computer-aided design package – an automated system for the design, drafting, and display of graphical information.
conceptual model – an interpretation or working description of the characteristics of the physical system.
continuous – a characteristic of an attribute that is conceptualized as a surface over some region. Examples are certain attributes of a resource, such as chemical stressor indicators measured in estuaries.
coordinates – linear and/or angular quantities that designate the position of a point in relation to a given reference frame.
data quality indicators – quantitative and qualitative measures of principal quality attributes, including precision, accuracy, representativeness, comparability, completeness, and sensitivity.
data quality assessment (DQA) – a statistical and scientific evaluation of the data set to determine the validity and performance of the data collection design and statistical test, and to determine the adequacy of the data set for its intended use.
data quality objectives (DQOs) – qualitative and quantitative statements derived from the DQO Process that clarify study objectives, define the appropriate type of data, and specify tolerable levels of potential decision errors that will be used as the basis for establishing the quality and quantity of data needed to support decisions.
data quality objectives process – a systematic planning tool to facilitate the planning of environmental data collection activities. Data quality objectives are the qualitative and quantitative outputs from the DQO Process.
data validation – an analyte- and sample-specific process that extends the evaluation of data beyond method, procedural, or contractual compliance (i.e., data verification) to determine the analytical quality of a specific data set.
data validation qualifier – code applied to the data by a data validator to indicate a verifiable or potential data deficiency or bias.
data validator – an individual (typically an independent third party) responsible for conducting data validation activities.
data verification – the process of evaluating the completeness, correctness, and conformance/compliance of a specific data set against the method, procedural, or contractual requirements.
data verifier – an individual (typically an employee of the field or laboratory organization whose operations are being verified) responsible for conducting data verification activities.
datum (plural datums) – in surveying, a reference system for computing or correlating the results of surveys. There are two principal types of datums: vertical and horizontal. A vertical datum is a level surface to which heights are referred. In the united states, the generally adopted vertical datum for leveling operations is the national geodetic vertical datum of 1929 (see below). The horizontal datum is used as a reference for position. The North American datum of 1927 (see below) is defined by the latitude and longitude of an initial point (Meade’s ranch in Kansas), the direction of a line between this point and a specified second point, and two dimensions that define the spheroid. The new north American datum of 1983 (see below) is based on a newly defined spheroid (grs80); it is an Earth-centered datum having no initial point or initial direction.
design – specifications, drawings, design criteria, and performance requirements. Also the result of deliberate planning, analysis, mathematical manipulations, and design processes.
digital elevation model – the representation of continuous elevation values over a topographic surface by a regular array of z-values, referenced to a common datum. Typically used to represent terrain relief.
digital line graph – digital data produced by the U.S. geological survey. These data include digital information from the U.S. geological survey map base categories such as transportation, hydrography, contours, and public land survey boundaries.
digital orthophotography – see orthophotography
digitizing table – an electronic device consisting of a flat surface and a handheld cursor that converts positions on the table to digital x, y coordinates.
document – any compilation of information which describes, defines, specifies, reports, certifies, requires, or provides data or results pertaining to environmental programs.
drylabbing – a laboratory may report analytical results without having actually performed the analyses. Results may be either invented from scratch, or previous legitimate results may be “borrowed” for inclusion in the present data package.
environmental conditions – the description of a physical medium (e.g., air, water, soil, sediment) or biological system expressed in terms of its physical, chemical, radiological, or biological characteristics.
environmental data – any measurements or information that describe environmental processes, location, or conditions; ecological or health effects and consequences; or the performance of environmental technology. For EPA, environmental data include information collected directly from measurements, produced from models, and compiled from other sources such as data bases or the literature.
environmental data operations – work performed to obtain, use, or report information pertaining to environmental processes and conditions.
environmental processes – manufactured or natural processes that produce discharges to, or that impact, the ambient environment.
environmental programs – work or activities involving the environment, including but not limited to: characterization of environmental processes and conditions; environmental monitoring; environmental research and development; and the design, construction, and operation of environmental technologies; and laboratory operations on environmental samples
environmental technology – an all-inclusive term used to describe pollution control devices and systems, waste treatment processes and storage facilities, and site remediation technologies and their components that may be utilized to remove pollutants or contaminants from or prevent them from entering the environment. Examples include wet scrubbers (air), soil washing (soil), granulated activated carbon unit (water), and filtration (air, water). Usually, this term applies to hardware based systems; however, it also applies to methods or techniques used for pollution prevention, pollutant reduction, or containment of contamination to prevent further movement of the contaminants, such as capping, solidification or vitrification, and biological treatment.
evaluation – a test of the model with known input
and output information that is used to assess that the calibration parameters
are accurate without further change and to demonstrate model performance.
extramural agreement – a legal agreement between EPA and an organization outside EPA for items or services to be provided. Such agreements include contracts, work assignments, delivery orders, task orders, cooperative agreements, research grants, state and local grants, and EPA-funded interagency agreements.
feature – an entity in a spatial data layer, such as a point, line, or polygon, that represents a geographic object.
Federal Geographic Data Committee – the Federal Geographic Data Committee (FGDC) coordinates the development of the National Spatial Data Infrastructure (NSDI). The NSDI encompasses policies, standards, and procedures for organizations to cooperatively produce and share geographic data. The 17 federal agencies that make up the FGDC are developing the NSDI in cooperation with organizations from state, local, and tribal governments, the academic community, and the private sector.
Federal Information Processing Standard – standards approved by the secretary of commerce under the information technology management reform act (public law 104-106). These standards and guidelines are issued by the National Institute of Standards and Technology (NIST) as Federal Information Processing Standards (FIPS) for use government-wide. FIPS coding standards include, for example, two-digit numeric codes used to identify each of the 50 U.S. states and three-digit numeric codes used to identify each U.S. county.
financial assistance – the process by which funds are provided by one organization (usually government) to another organization for the purpose of performing work or furnishing services or items. Financial assistance mechanisms include grants, cooperative agreements, and government interagency agreements.
focused data validation – a detailed investigation of particular data records identified by the data user that need interpretation or review.
geographic feature – see feature.
Geographic Information System – a collection of computer hardware, software, and geographic data designed to capture, store, update, manipulate, analyze, and display geographically referenced data.
geospatial data – the information that identifies the geographic location and characteristics of natural or constructed features and boundaries on the earth. This information may be derived from, among other things, remote-sensing, mapping, and surveying technologies.
Global Positioning System (GPS) – a constellation of 24 satellites, developed by the U.S. department of Defense, that orbit the earth at an altitude of 20,200 kilometers. These satellites transmit signals that allow a GPS receiver anywhere on earth to calculate its own location. The global positioning system is used in navigation, mapping, surveying, and other applications where precise positioning is necessary.
graded approach – the process of basing the level of application of managerial controls applied to an item or work according to the intended use of the results and the degree of confidence needed in the quality of the results.
grid – a data structure commonly used to represent map features. A cellular-based data structure composed of cells or pixels arranged in rows and columns (also called a raster).
ground-truthing – the use of a ground survey to confirm the findings of an aerial survey or to calibrate quantitative aerial or satellite observations.
imagery – visible representation of objects and/or phenomena as sensed or detected by cameras, infrared, and multispectral scanners, radar, and photometers. Recording may be on photographic emulsion (directly, as in a camera, or indirectly, after being first recorded on magnetic tape as an electrical signal) or on magnetic tape for subsequent conversion and display on a cathode ray tube.
independent assessment – an assessment performed by a qualified individual, group, or organization that is not a part of the organization directly performing and accountable for the work being assessed.
inspection – an activity such as measuring, examining, testing, or gauging one or more characteristics of an entity and comparing the results with specified requirements in order to establish whether conformance is achieved for each characteristic.
juicing – fortification of a sample with additional analyte such as re-spiking a spiked sample or adding peak area. See also peak enhancement and peak juicing.
kriging – a weighted, moving-average estimation technique based on geostatistics that uses the spatial correlation of point measurements to estimate values at adjacent, unmeasured points. A sophisticated technique for filling in missing data values, kriging is named after a South African engineer, D.G. Krige, who first developed the method. The kriging routine preserves known data values, estimates missing data values, and estimates the variance at every missing data location. After kriging, the filled matrix contains the best possible estimate of the missing data values, in the sense that the variance has been minimized.
laboratory qualifier – code applied
to the data by a contract analytical laboratory to indicate a
verifiable or potential data deficiency or bias.
landsat – a series of orbiting satellites used to acquire remotely sensed images of earth’s land surface and surrounding coastal regions.
leaf on/leaf off – the characteristic of deciduous vegetation based on seasonality. Refers to whether deciduous trees have leaves during image acquisition.
locational – of or referring to the geographic position of a feature.
management – those individuals directly responsible and accountable for planning, implementing, and assessing work.
management assessment – the qualitative assessment of a particular program operation and/or organization(s) to establish whether the prevailing quality management structure, policies, practices, and procedures are adequate for ensuring that the type and quality of results needed are obtained. A management assessment may either be performed by those immediately responsible for overseeing and/or performing the work (i.e., a management self-assessment) or by someone other that the group performing the work (i.e., a management independent assessment).
management system – a structured non-technical system describing the policies, objectives, principles, organizational authority, responsibilities, accountability, and implementation plan of an organization for conducting work and producing items and services.
management systems review (MSR) – the qualitative assessment of a data collection operation and/or organization(s) to establish whether the prevailing quality management structure, policies, practices, and procedures are adequate for ensuring that the type and quality of data needed are obtained.
map digitization – conversion of map data from graphic to digital form.
map projection – a mathematical formula or algorithm for translating the coordinates of features on the surface of the earth to a plane for representation on a flat map.
map resolution – the accuracy with which the location and shape of map features are depicted for a given map scale.
map scale – a statement of a measure on the map and the equivalent measure on the earth, often expressed as a representative fraction of distance, such as 1:24,000.
map, thematic – map designed to provide information on a single topic, such as geology, rainfall, or population.
measurement and testing equipment – tools, gauges, instruments, sampling devices or systems used to calibrate, measure, test, or inspect in order to control or acquire data to verify conformance to specified requirements.
measurement quality objectives – "acceptance criteria" for the quality attributes measured by project data quality indicators. During project planning, measurement quality objectives are established as quantitative measures of performance against selected data quality indicators, such as precision, bias, representativeness, completeness, comparability, and sensitivity.
metadata – information about a data set. Metadata for geographical data may include the source of the data; its creation date and format; its projection, scale, resolution, and accuracy; and its reliability with regard to some standard.
method – a body of procedures and techniques for performing an activity (e.g., sampling, chemical analysis, quantification) systematically presented in the order in which they are to be executed.
method, accuracy, and description data (MAD) – a coding scheme developed by EPA to promulgate standards for describing the type and quality of spatial data. The coding scheme includes both database field definitions and standardized codes.
model calibration – the process of refining the model representation of the environmental framework, properties, and boundary conditions to achieve a desired degree of correspondence between the model simulations and observations of the environmental system and processes. The focus is usually on the estimation and characterization of empirical constants used in parameterizations and mathematical representations of environmental processes.
modeling – development of a mathematical or physical representation of a system or theory that accounts for all or some of its known properties. Models are often used to test the effect of changes of components on the overall performance of the system.
National geodetic vertical datum of 1929 – reference surface established by the NIST coast and Geodetic survey in 1929 as the datum to which relief features and elevation data are referenced in the conterminous united states; formerly called “mean sea level 1929.”
National hydrography data set – a comprehensive set of digital spatial data that contains information about surface water features such as lakes, ponds, streams, rivers, springs, and wells.
National map accuracy standards – specifications promulgated by the U.S. office of management and budget to govern accuracy of topographic and other maps produced by federal agencies.
National institute of standards and technology – a non-regulatory federal agency within the U.S. Commerce department’s technology administration whose mission is to develop and promote measurement, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life. NIST laboratories provide technical leadership for vital components of the nation’s technology infrastructure needed by U.S. industry to continually improve its products and services.
National land cover data – a nationally consistent land-cover data set developed by the national Land cover characterization program.
National spatial data infrastructure – the technologies, policies, and people necessary to promote sharing of geospatial data throughout all levels of government, the private and nonprofit sectors, and the academic community. The NSDI was established in 1994 by executive order 12906.
North American datum of 1927 – the primary local geodetic datum used to map the united states during the middle part of the 20th century, reference to the Clarke spheroid of 1866 and an initial point at Meade’s ranch, Kansas. Features on U.S. geological survey topographic maps, including the corners of 7.6-minute quadrangle maps, are referenced to this datum. It is gradually being replaced by the North American datum of 1983.
North American datum of 1983 – a geocentric datum
based on the geodetic reference system
1980 ellipsoid (grs80). Its measurements are obtained from both terrestrial
and satellite data.
observation – an assessment conclusion that identifies a condition (either positive or negative) which does not represent a significant impact on an item or activity. An observation may identify a condition which does not yet cause a degradation of quality.
organization – a company, corporation, firm, enterprise, or institution, or part thereof, whether incorporated or not, public or private, that has its own functions and administration. In the context of this Manual, an EPA organization is an office, region, national center or laboratory.
orthophotography – perspective aerial photography from which distortions owing to camera tilt and ground relief have been removed. Orthophotography has the same scale throughout and can be used as a map.
participant – when used in the context of environmental programs, an organization, group, or individual that takes part in the planning and design process and provides special knowledge or skills to enable the planning and design process to meet its objective.
peer review – a documented critical review of work by qualified individuals (or organizations) who are independent of those who performed the work, but are collectively equivalent in technical expertise. A peer review is conducted to ensure that activities are technically adequate, competently performed, properly documented, and satisfy established technical and quality requirements. The peer review is an in-depth assessment of the assumptions, calculations, extrapolations, alternate interpretations, methodology, acceptance criteria, and conclusions pertaining to specific work and of the documentation that supports them.
peak shaving – manually adjusting the raw data by reducing a peak area that is out of specification.
peak enhancement – manually adjusting the raw data by increasing a peak area that is out of specification. See also juicing and peak juicing.
peak juicing – manually adjusting the raw data by increasing a peak area that is out of specification.
performance criteria – measures of data quality that are used to judge the adequacy of collected information that is new or original, otherwise known as “primary data.”
performance evaluation (PE) – a type of audit in which the quantitative data generated in a measurement system are obtained independently and compared with routinely obtained data to evaluate the proficiency of an analyst or laboratory.
photogrammetry – science or art of obtaining reliable measurements or information from photographs or other sensing systems.
positional accuracy – the closeness of locational information to its true position.
precision – (i) the degree to which replicate measurements of the same attribute agree or are exact. Precision is the degree to which a set of observations or measurements of the same property, usually obtained under similar conditions, conform to themselves. A data quality indicator (see related : Accuracy, bias). (ii) the number of significant decimal places used to store floating point numbers (e.g., coordinates) in a computer. Single precision denotes use of up to seven significant digits to store floating point numbers. Double precision denotes use of up to 14 significant digits to store floating point numbers. (iii) a measure of mutual agreement among individual measurements of the same property, usually under prescribed similar conditions, expressed generally in terms of the standard deviation.
process – a set of interrelated resources and activities which transforms inputs into outputs. Examples of processes include analysis, design, data collection, operation, fabrication, and calculation.
projection – a mathematical model that transforms the locations of features on the earth’s surface to locations on a two-dimensional surface.
quality - the totality of features and characteristics of a product or service that bear on its ability to meet the stated or implied needs and expectations of the user.
quality assurance (QA) – an integrated system of management activities involving planning, implementation, documentation, assessment, reporting, and quality improvement to ensure that a process, item, or service is of the type and quality needed and expected by the customer.
quality assurance manager (QAM) – the individual designated as the principal manager within the organization having management oversight and responsibilities for planning, documenting, coordinating, and assessing the effectiveness of the quality system for the organization.
quality assurance project plan (QAPP) – a document describing in comprehensive detail the necessary QA, QC, and other technical activities that must be implemented to ensure that the results of the work performed will satisfy the stated performance criteria.
quality control (QC) – the overall system of technical activities that measures the attributes and performance of a process, item, or service against defined standards to verify that they meet the stated requirements established by the customer; operational techniques and activities that are used to fulfill requirements for quality.
quality improvement – a management program for
improving the quality of operations. Such
management programs generally entail a formal mechanism for encouraging
worker
recommendations with timely management evaluation and feedback or implementation.
quality management – that aspect of the overall management system of the organization that determines and implements the quality policy. Quality management includes strategic planning, allocation of resources, and other systematic activities (e.g., planning, implementation, documentation, and assessment) pertaining to the quality system.
quality management plan (QMP) – a document that describes a quality system in terms of the organizational structure, policy and procedures, functional responsibilities of management and staff, lines of authority, and required interfaces for those planning, implementing, documenting, and assessing all activities conducted.
quality system – a structured and documented management system describing the policies, objectives, principles, organizational authority, responsibilities, accountability, and implementation plan of an organization for ensuring quality in its work processes, products (items), and services. The quality system provides the framework for planning, implementing, documenting, and assessing work performed by the organization and for carrying out required QA and QC activities.
raster data (raster image) – a spatial data model made of rows and columns of cells. Each cell contains an attribute value and location coordinates; the coordinates are contained in the order of the matrix, unlike a vector structure, which stores coordinates explicitly. Groups of cells that share the same value represent geographic features.
readiness review – a systematic, documented review
of the readiness for the start-up or
continued use of a facility, process, or activity. Readiness reviews are
typically conducted before proceeding beyond project milestones and prior
to initiation of a major phase of work.
record – a completed document that provides objective evidence of an item or process. Records may include photographs, drawings, magnetic tape, and other data recording media.
remote sensing – process of detecting and/or monitoring chemical or physical properties of an area by measuring its reflected and emitted radiation.
root mean square error – the square root of the average of the set of squared differences between dataset coordinate values and coordinate values from an independent source of higher accuracy for identical points.
representativeness – the degree to which data accurately and precisely represent the frequency distribution of a specific variable in the population.
scale – relationship existing between a distance on a map, chart, or photograph and the corresponding distance on the earth.
scientific method – the principles and processes regarded as necessary for scientific investigation, including rules for concept or hypothesis formulation, conduct of experiments, and validation of hypotheses by analysis of observations.
self-assessment – assessments of work conducted by individuals, groups, or organizations directly responsible for overseeing and/or performing the work.
sensitivity – the variation in the value of one or more output variables or quantities calculated from the output variables due to variability or uncertainty in one or more inputs to a model.
sensitivity analysis – a quantitative evaluation of the impact of variability or uncertainty in model inputs on the degree of calibration of a model and on its results or conclusions.
simulation – one complete execution of the computer program, including input and output.
Soil survey geographic (SSURGO) data – a nationwide, geospatial, soils database created by the Natural resources conservation service from 1:250,000-scale soil maps.
source code – the program instructions written in a programming language [FIPS PUB 106 (NIST) definition].
specification – a document stating requirements and which refers to or includes drawings or other relevant documents. Specifications should indicate the means and the criteria for determining conformance.
spheroid – an ellipsoid that approximates a sphere. Used to describe (approximately) the shape of the earth.
SSURGO – see soil survey geographic data.
standard operating procedure (SOP) – a written document that details the method for an operation, analysis, or action with thoroughly prescribed techniques and steps, and that is officially approved as the method for performing certain routine or repetitive tasks.
supplier – any individual or organization furnishing items or services or performing work according to a procurement document or financial assistance agreement. This is an all-inclusive term used in place of any of the following: vendor, seller, contractor, subcontractor, fabricator, or consultant.
surveillance (quality) – continual or frequent monitoring and verification of the status of an entity and the analysis of records to ensure that specified requirements are being fulfilled.
Technical assessment – the evaluation process used to measure the performance or effectiveness of a technical system and its elements with respect to documented specifications and objectives. Such assessments may include qualitative and quantitative evaluations. A technical assessment may either be performed by those immediately responsible for overseeing and/or performing the work (i.e., a technical self-assessment) or by someone other that the group performing the work (i.e., a technical independent assessment).
technical review – a documented critical review of work that has been performed within the state of the art. The review is accomplished by one or more qualified reviewers who are independent of those who performed the work, but are collectively equivalent in technical expertise to those who performed the original work. The review is an in-depth analysis and evaluation of documents, activities, material, data, or items that require technical verification or validation for applicability, correctness, adequacy, completeness, and assurance that established requirements are satisfied.
technical systems audit (TSA) – a thorough, systematic, on-site, qualitative audit of facilities, equipment, personnel, training, procedures, record keeping, data validation, data management, and reporting aspects of a system.
tic – a point on a map representing a location whose coordinates are known in some system of ground measurement such as latitude and longitude.
time-traveling – falsification of the date of analysis in the laboratory’s data system in order to conceal such things as exceeding a holding time or bringing a satellite’s time-frame within required time period.
topography – configuration (relief) of the land surface; the graphic delineation or portrayal of that configuration in map form, as by contour lines. In oceanography the term is applied to a surface such as the sea bottom or surface of given characteristics within the water mass.
Topologically Integrated Geographically Encoding and Referencing (TIGER) system – the data system developed by the U.S. census bureau to describe the boundaries of all census geography (e.g., states, counties, census tracts) and to tie decennial census tabulations to census boundaries.
topology – the spatial relationships between connecting or adjacent features in a geographic data layer. Topological relationships are used for spatial modeling operations that do not need coordinate information.
uncertainty – lack of knowledge about specific factors, parameters, or models
user – an organization, group, or individual that utilizes the results or products from environmental programs or a customer for whom the results or products were collected or created.
validation – confirmation by examination and provision of objective evidence that the particular requirements for a specific intended use are fulfilled. In design and development, validation concerns the process of examining a product or result to determine conformance to user needs.
variability – observed differences attributable to true heterogeneity or diversity in a population or exposure parameter (variability can be better characterized but not reduced by further measurement or study).
vector – a data structure used to represent linear geographic features. Features are made of ordered lists of x, y coordinates and represented by points, line, or polygons; points connect to become lines, and lines connect to become polygons. Attributes are associated with each feature.
verification – confirmation by examination and
provision of objective evidence that specified requirements have been
fulfilled. In design and development, verification concerns the process
of examining a result of a given activity to determine conformance to
the stated requirements for that activity.