Quality control (QC)
“The overall system of technical activities whose purpose is to
measure and control the quality of a product or service so that it
meets the needs of users. The aim is to provide quality that is
satisfactory, adequate, dependable, and economical.” In EMAP,
quality control consists of specific steps taken during the data
collection process to ensure that equipment and procedures are
operating as intended and that they will allow data quality objectives to be achieved.
QA/QC
Quality Assurance/Quality Control. “A system of procedures,
checks, audits, and corrective actions to ensure that all USEPA
research design and performance, environmental monitoring and
sampling, and other technical and reporting activities are of the
highest achievable quality.”
Quantile
The value of an attribute indexing a specified proportion of a
population distribution or distribution function. Quartiles (25th,
50th, and 75th percentiles), the median (50th percentile), and
other percentiles are special cases of quantiles.
Recovery
The partial or full return of a population or community to a condition that existed before the introduction of the stressor.
Randomization
The process of imposing an element of chance on the selection of a
sample. Randomization is a step in the design protocol and may take
many forms; it is the basis for determining the design-based properties of the resulting probability sample.
Reference condition
The set of attributes of ecological resources that assist in identifying
the location of a portion of the resource population along a condition continuum from the worst possible condition to the best possible condition given the prevailing topography, soil, geology,
potential vegetation, and general land use of the region. Reference
condition typically refers to the best resource condition, but it is
used more broadly in EMAP.
Reference site
One of a population of benchmark or control sampling locations
that, taken collectively, represent an ecoregion or other large biogeographic area; the sites, as a whole, represent the best ecological
conditions that can be reasonably attained, given the prevailing
topography, soil, geology, potential vegetation, and general land
use of the region or clearly subnominal condition
Region
Any explicitly defined geographic area. In the EMAP objectives,
region refers to the ten standard federal regions.
Relation
The concept of function, correlation, or association between or
among attributes, which may be qualitative as well as quantitative.
Representativeness
“The degree to which data accurately and precisely represent the
frequency distribution of a specific variable in the population; a data
quality indicator.”
Research project
A single, focused activity with a single primary research objective.
The project includes the entire research process of initial planning,
conduct of research (including fieldwork if necessary), and evaluation (analysis and reporting). A research project involving fieldwork
may require several years to complete. Many EMAP research projects will not require fieldwork: such projects include development
of conceptual models for an indicator, development of a proposed
national sampling design strategy, analysis of existing data for
indicator development, and others.
5 Geographic Information Systems and Remote Sensing Applications in Environmental. . . 229
“The overall system of technical activities whose purpose is to
measure and control the quality of a product or service so that it
meets the needs of users. The aim is to provide quality that is
satisfactory, adequate, dependable, and economical.” In EMAP,
quality control consists of specific steps taken during the data
collection process to ensure that equipment and procedures are
operating as intended and that they will allow data quality objectives to be achieved.
QA/QC
Quality Assurance/Quality Control. “A system of procedures,
checks, audits, and corrective actions to ensure that all USEPA
research design and performance, environmental monitoring and
sampling, and other technical and reporting activities are of the
highest achievable quality.”
Quantile
The value of an attribute indexing a specified proportion of a
population distribution or distribution function. Quartiles (25th,
50th, and 75th percentiles), the median (50th percentile), and
other percentiles are special cases of quantiles.
Recovery
The partial or full return of a population or community to a condition that existed before the introduction of the stressor.
Randomization
The process of imposing an element of chance on the selection of a
sample. Randomization is a step in the design protocol and may take
many forms; it is the basis for determining the design-based properties of the resulting probability sample.
Reference condition
The set of attributes of ecological resources that assist in identifying
the location of a portion of the resource population along a condition continuum from the worst possible condition to the best possible condition given the prevailing topography, soil, geology,
potential vegetation, and general land use of the region. Reference
condition typically refers to the best resource condition, but it is
used more broadly in EMAP.
Reference site
One of a population of benchmark or control sampling locations
that, taken collectively, represent an ecoregion or other large biogeographic area; the sites, as a whole, represent the best ecological
conditions that can be reasonably attained, given the prevailing
topography, soil, geology, potential vegetation, and general land
use of the region or clearly subnominal condition
Region
Any explicitly defined geographic area. In the EMAP objectives,
region refers to the ten standard federal regions.
Relation
The concept of function, correlation, or association between or
among attributes, which may be qualitative as well as quantitative.
Representativeness
“The degree to which data accurately and precisely represent the
frequency distribution of a specific variable in the population; a data
quality indicator.”
Research project
A single, focused activity with a single primary research objective.
The project includes the entire research process of initial planning,
conduct of research (including fieldwork if necessary), and evaluation (analysis and reporting). A research project involving fieldwork
may require several years to complete. Many EMAP research projects will not require fieldwork: such projects include development
of conceptual models for an indicator, development of a proposed
national sampling design strategy, analysis of existing data for
indicator development, and others.
5 Geographic Information Systems and Remote Sensing Applications in Environmental. . . 229