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Friday, 17 November 2006 01:00 |
A Detection Level is the lowest "measurable” analyte Concentration by a specified method.
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Detection Limit
The lowest Concentration or amount of the target analyte
that can be determined to be different from zero by a single measurement at a stated level of probability.
Deviation
An abnormality or a departure from what is required or expected.
In numerical data sets, the difference or distance of an individual observation or data value from the center point (often the mean) of the set distribution.[1]
Dispersion
The degree of "data scatter” (random disposition) around the data mean or median.
Distribution
The concentration of an element at a point over time, over an area, or within a volume; a probability function (density function, mass function, distribution function) used to describe a set of observations (statistical sample) or a population from which the observations are generated.
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Document Control
The policies and procedures used by an organization to ensure that its written activities and reports, and their revisions, are reviewed, approved for release, inventoried, distributed, archived, stored, and retrieved in accordance with the organization"s requirements.
Environmental Conditions
The description of a physical medium (e.g., air, water, soil, or sediment) or biological system expressed in terms of its physical, chemical, radiological, or biological characteristics.
Environmental Data
Any measurements or information that describe natural processes, locations, or conditions; ecological or health effects and consequences; or the performance of technology dealing with natural process; and, for EPA, information collected directly from measurements, produced from models, and compiled from other sources such as mathematical repositories or the literature.
Environmental Data Operation
Work performed to obtain, use, or report information pertaining to natural surroundings and conditions.
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Environmental Monitoring
The process of measuring or collecting information on natural surroundings.
Environmental Processes
Any manufactured or natural events that produce discharges to, or that impact, the natural state.
Environmental Programs
An all-inclusive term pertaining to any work or activities involving the natural ecological condition, including but not limited to: characterization of processes and conditions; monitoring; research and development; the design, construction, and operation of technologies; and laboratory operations on samples.
Environmental Technology
An all-inclusive term used to describe pollution control devices and systems, waste treatment processes and storage facilities, and site remediation techniques and their components that may be utilized to remove pollutants or contaminants from or prevent them from entering the natural sphere.
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Equivalent Method
Any process or protocol, whether sampling or analytical, which can be demonstrated as an acceptable alternative to the reference or standard process or protocol.
Error
A deviation from that which is correct, true, or right; a discrepancy of a computed, calculated, or measured value from the true or correct condition; a mistake made. See also random error.
Estimate
A characteristic from the sample from which inferences on parameters can be made; a prediction of the likelihood of an event occurrence, a quantitative result, or cost.
Extramural Agreement
A legal arrangement between EPA and an organization outside EPA for items or services to be provided. This includes contracts, work assignments, delivery orders, task orders, cooperative agreements, research grants, state and local grants, and EPA-funded interagency agreements.
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Evidentiary Records
Documents identified as part of litigation process and therefore subject to restricted access, custody, use, and disposal.
Experimental Design
The organized plan for a data collection activity
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.[1]
False Acceptance Decision Error
A result that occurs as a decision maker accepts the null hypothesis (baseline condition) when it is actually false; also can be referred to as a false negative decision error or a Type II error.
False Negative
A result that occurs when the sample or environmental condition is reported not to contain an analyte, microorganism, etc., when the sample actually does.
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False Negative Decision Error
A result that occurs when the decision maker accepts the null hypothesis (baseline condition) when it is really false; also called a Type II error.
False Positive
The result that occurs when a sample is reported to contain an analyte, microorganism, etc., when it actually does not contain the analyte.
False Positive Decision Error
A result that occurs as a decision maker rejects the null hypothesis (baseline condition) when it is really true; also called a Type I error.
False Rejection Decision Error
A result that occurs when a decision maker rejects the null hypothesis (baseline condition) when it is really true; also known as a Type I error. Occasionally may be called a false positive decision error.
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Feasibility Study
An evaluation of the practicality or viability of an idea.
Field Duplicate, Co-located
An independent specimen collected from the same point in time and space as the previous specimen.
Field Duplicate, Subsample
A test specimen that is homogenized before being divided into two or more portions with the same laboratory analyzing all portions.
Field Measurements
Those activities associated with performing analyses or measurements in the habitat being examined.
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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 and which include grants, cooperative agreements, and government interagency agreements.
Finding
An assessment conclusion, either positive or negative, that identifies a condition having a significant effect on an item or activity and which is normally accompanied by specific examples of the observed condition.
Frequency Distribution (statistical)
A graphical representation of the dispersion of the different values of a variable that shows their observed occurrence.
Geographical Information System (GIS)
A collection of computer hardware, software, and physical data designed to capture, store, manipulate, analyze, and display habitat referenced data.
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Geospatial Data
The information that identifies the geographic location and characteristics of natural or constructed features and boundaries on the earth.
Good Laboratory Practices (GLPs)
The established guidelines to ensure reporting of high quality and reliable data to support the research or marketing efforts for experimentation or product manufacturing processes regulated by governmental agencies; see 40 CFR Part 160, 40 CFR Part 792, and 21 CFR Part 58.
Grab Samples
Discrete subsets of a population thought to be representative of a specific area and a specific time, not necessarily taken at random.
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.
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Gray Region/ Gray Area
The range of true parameter values where the consequences of making a decision error are relatively minor; a component of the quantitative decision performance criteria.
Grid
A network of lines arranged in a systematic pattern with each delineated component being of equal size.
Grid Sampling
A statistical method for determining collection sites for subsets of a population where the sites are located at the nodes or interior of all or some of delineated pattern.
Ground-Truthing
The use of an on-the-land survey to confirm the findings of an aerial survey or to calibrate quantitative aerial or satellite observations.
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Guidance
A suggested practice that is not mandatory, but intended as an aid or example in complying with a standard or requirement.
Historical Data
Previously collected information from one or more projects which may or may not be useful for a new purpose. Also known as existing data or secondary data.
Hypothesis Test
A statistical procedure for determining if a sample provides sufficient evidence to reject or accept one statement regarding the population of interest in favor of an alternative statement.
Implementation Phase
The onset of actions necessary to turn planned activities into actions started so that the project"s goals or deliverables can be achieved.
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Independence
The lack of a causal relationship between things, regardless of their statistical correlation; freedom from bias and external influences that could affect objectivity.
Independent Assessment
An evaluation performed by a qualified individual, group, or organization that is not part of the organization directly performing and accountable for the work being assessed.
Indicators
Items, elements, or measures used to determine or identify a basic condition or how well a process or program is meeting its objectives.
Established measures used to determine how well an organization is meeting its customers' needs as well as other operational and financial performance expectations.[1]
Influential Information
Information that the Agency can reasonably determine that its dissemination will have or does have a clear and substantial impact (potential change or effect) on important public policies or private sector decisions.
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Information Dissemination
Agency sponsored distribution of information to the public (important exclusions apply under the EPA's Information Quality Guidelines2 [EXIT Glossary]).
Information Distribution
Any release of documentation to the public.
Information Integrity
The security of information, such as protection from unauthorized access or revision, to ensure that it is not compromised through corruption or falsification.
Information Objectivity
Information that is accurate, clear, complete, and unbiased in presentation and substance. See also the EPA's Information Quality Guidelines2 [EXIT Glossary].
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Information Quality
The objectivity, utility, and integrity of the information as described in the EPA's Information Quality Guidelines2 [EXIT Glossary].
Information Resources Management
The planning, budgeting, organizing, directing, training, and controls associated with the collected findings and which encompasses related resources such as personnel, equipment, funds, and technology.
Information Transparency
The inclusion of source references (citations) and possible clarifications for the information being disseminated.
Information Utility
The usefulness of the information to the intended users.
Inherently Governmental Functions
"A function which is so intimately related to the public interest as to mandate performance by Government employees. ....These functions include those activities which require either the exercise of discretion in applying Government authority or the use of value judgment in making decision for the Government.” (OMB circular A-763 1 and supplemental guidance).
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Inspection
The examination, measurement, or testing of an item or activity to verify conformity to specific requirements.
Instrument Detection Level (IDL)
The lowest concentration of an analyte that, when directly inputted and processed on a specific piece of analytical equipment, produces a signal/response that is statistically distinct from the signal/response arising from equipment "noise” alone.
Interference
An element, compound, or other matrix effect present in a sample which disturbs the detection of a target analyte leading to inaccurate concentration results for the target analyte.
Judgmental Sampling
Use of professional opinion and experience to select specimen collection locations.
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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.
Laboratory Control Sample (LCS)
A specimen of known composition prepared using contaminant-free reagent water, or an inert solid, that is spiked with the analyte of interest at the midpoint of the calibration curve or at the level of concern; and then analyzed using the same preparation, reagents, and analytical methods employed for regular specimens and at the intervals set in the QA Project Plan.
Laboratory Duplicates
Two or more representative portions taken from one homogeneous sample by the analyst and analyzed in the same testing facility.
Laboratory Data Qualifier
Code applied to the data by the analytical testing facility to indicate a verifiable or potential data deficiency or bias.
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Limit of Quantitation (LOQ)
The minimum amount of an analyte that demonstrates a reproducible signal or response such that the specified quality criteria for precision and accuracy are met.
Locational Data
Latitude/longitude coordinates and other geographic information collected.
Management System
An organizational structure which concerns policies, objectives, principles, organizational authority, responsibilities, accountability, and implementation plan for conducting work and producing items and services.
Management Systems Review (MSR)
The qualitative assessment of an organization"s data collection operation or program used to establish whether the organization"s prevailing quality system, i.e., quality management structure, policies, practices, and procedures, is adequate for ensuring that the type and quality of data needed are obtained.
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Matrix
The material of which the sample is composed or the substrate containing the analyte of interest, such as drinking water, waste water, air, soil/sediment, biological material, etc. Also called medium or media.
Matrix Spike Sample
A test specimen prepared by adding a known concentration of the target analyte to a specified amount of a specific homogenized specimen where an estimate of the target concentration is available and subjected to the entire analytical protocol.
Matrix Spike Duplicate
A sample prepared simultaneously as a split with the matrix spike sample with each specimen being spiked with identical, known concentrations of targeted analyte.
Maximum Holding Time
The longest temporal period a sample may be held after collection and before analysis.
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Mean
The arithmetic average; a measure of central tendency.
Measurement Error
The difference between the true or actual state and that which is reported.
Measurement Quality Objectives
The specified performance criteria used in a sampling and analysis plan for indicators such as precision, bias, completeness, etc.
Median
The middle value for an ordered set of data values; the central value when "n” is odd, or by the average of the two most central values when "n” is even; the 50th percentile.[1]
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Metadata
The information about a data set which may include descriptive information about the context, quality and condition, or characteristics of a data set. For geographical data this 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 procedure, technique, or tool for performing a scientific activity.
Method Detection Limit
The minimum concentration of an analyte that undergoes the entire measurement process and can be reported with a stated level of confidence that the analyte concentration is greater than zero.
Methodology
A documented process or procedure for describing the philosophy of and procedures for performing a sequence of events, such as an analytical process, management of project activities, or the manner in which data are to be evaluated.
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Metric
A standard of measurement.
Model
The representation of a system, such as a watershed, by something other than the system itself, e.g., a schematic or a mathematical interpretation. See computer model; conceptual model.
Model Calibration
The process of refining or adjusting the parameters (framework, properties, and boundary conditions) to achieve a desired degree of correspondence between the mathematical simulations and observations of the system and its processes.
Natural Variability
The inconstancy that is inherent or natural to the media, objects, processes, or biota being studied.
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Non-Conformity, Major
An indication or judgment that a process, product, or service has not met all the requirements and will likely impact the user"s ability to use the product.
Non-Conformity, Minor
An indication or judgment that a process, product, or service has isolated discrepancies from the stated requirements which may or may not significantly impact the product.
Nonparametric Tests
All studies involving ranked data, i.e., data that can be put in order and used when there is no assumption that the population has a normal distribution or when the population is known to have low and high values and valuable in detecting population differences when certain assumptions are not satisfied.
Nonparametric tests are often used in place of their parametric counterparts when certain assumptions about the underlying population are questionable. For example, when comparing two independent samples, the Wilcoxon Mann-Whitney test does not assume the difference between the samples is normally distributed, whereas its parametric counterpart, the two-sample t-test, does. Nonparametric tests may be, and often are, more powerful in detecting population differences when certain assumptions are not satisfied. All tests involving ranked data (data that can be put in order) are nonparametric.[1]
Normal Distribution (statistical)
The frequency of data occurrence where most of the data points are located near the mean; seen statistically as a symmetrical bell-shaped curve.
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Objective
The element or statement that an individual or an organization wishes to accomplish and to which their efforts are directed.
A specific statement of a desired short term condition or achievement; includes measurable end results to be accomplished by specific teams or individuals within time limits.[1]
Objective Evidence
A documented statement of fact, other information, or a record, quantitative or qualitative, pertaining to the quality of an item or activity, based on observations, measurements, or tests which can be verified.
Observation
An assessment that identifies a condition (either positive or negative); when used in observational studies, the measure and record variables of interest.
Outlier
An extreme observation that is shown to have a low probability of belonging to a specified data population; any item rejected by the sampler, analyst, or data reviewer, usually accompanied by an attendant explanation.
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Oversight
The independent assessment of the quality system and/or projects for conformance with requirements, effectiveness of requirements in maintaining quality, and ensuring or effecting appropriate corrective action.
Parameter
A statistical quantity, usually unknown, such as a mean or a standard deviation, which characterizes a population or defines a system. Commonly misused as a synonym for "variable,” "characteristic,” or "property.”
Peer Review
A documented in-depth critical examination of a proposed or actual product, generally beyond the state of the art or characterized by the existence of potential uncertainty, conducted by qualified individuals (or an organization) independent of those who performed the work but collectively equivalent in technical expertise to those who performed the original work.
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.”
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Performance Curve
The probability of deciding that the parameter of interest is greater than action level over the range of possible population parameters and which is used to assess the goodness of a test or to compare two competing tests; similar in concept to a statistical power curve
Poisson Distribution
A probability distribution used in the statistical analysis of events which resembles the binomial distribution in that it models counts of events.
Population
The total collection or entire group of interest, such as observations, objects, or people, to be studied and from which a sample is to be taken.
Positional Accuracy
The closeness of locational information to its true position or position in relation to an accepted standard.
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Positive Control Sample
A prepared standard which undergoes an analytical procedure to provide comparison with an unknown specimen thereby monitoring recovery to assure that a test and/or its components are working properly and producing correct or expected results. In microbiology this would be a positive culture control.
Power Curve
The probability of rejecting the baseline condition over the range of the population.
Precision
A measure of mutual agreement between two or more individual measurements of the same property, obtained under similar conditions.
Pre-Dissemination Review
An oversight mechanism to facilitate a decision that information about to be disseminated meets the Information Quality Guidelines2 [EXIT Glossary] or other relevant standards.
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Probability
A measure of the likelihood or chance of something happening.
A term referring to the likelihood of occurrence of an event, action or item.[1]
Probability-Based Sampling
A method of specimen collection such that the relative probability of a significant constituent is being included in the specimen is mathematically predicable.
Process
A set of interrelated or interacting activities which transforms inputs into outputs.
Proficiency Test (PT)
A type of external assessment in which a stable sample, the composition of which is unknown to the analyst, is provided to determine whether the analyst/laboratory can produce analytical results within the specified acceptance criteria. Also known as a Performance Evaluation Test.
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Proficiency Test (PT) Sample
A test specimen that mimics an actual specimen in all possible aspects, except that its composition is unknown to the laboratory at the time of analysis, which is used to assess the laboratory"s capability to produce results within acceptable criteria. Also known as a Performance Evaluation Sample.
Project Life Cycle
The sequence of major events in a process, such as systematic planning, development of appropriate documentation (QA Project Plans and Standard Operating Procedures), execution of the planned events (sampling, analysis, and data review), assessments of work conducted, and development of the final product (publication) and action to be taken based on the project results.
Protocol
The documented or standardized procedure or detailed plan to be followed in a test, process, or method. See also Standard Operating Procedure.
Qualified Data
Any numerical information that has been modified or adjusted by mathematical or statistical operations and which may be limited in use for a specific function.
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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, i.e., fitness for use.
Quality Assurance (QA)
An integrated system of management activities (planning, implementation, assessment, reporting, and quality improvement) that focuses on providing confidence in the data or product by ensuring that it is of the type and worth needed and expected by the client.
Quality Assurance Manager/Officer/ Coordinator
The individual designated within an organization having management oversight and responsibilities for planning, documenting, coordinating, and assessing the system effectiveness for ensuring the value of the work.
Quality Assurance Project Plan (QAPP)
A document that describes the intended technical activities and project procedures that will be implemented to ensure that the results of the work to be performed will satisfy the stated performance or acceptance criteria. The amount of information presented and the planned activities to ensure the value of the work will vary according the type of study and the intended use of the data.
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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.
Quality Control Sample
One of any number of test specimens, such as a Proficiency Test or blank, intended to demonstrate that a measurement system or activity is in check.
Quality Improvement
A management program for improving the quality of operations.
Quality Management
The application of a quality management system in managing a process to achieve maximum customer satisfaction at the lowest overall cost to the organization while continuing to improve the process.[1]
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Quality Management Plan (QMP)
A document that describes an organization"s system in terms of its organizational structure, policy and procedures, staff functional responsibilities, lines of authority, and interfaces for those planning, implementing, documenting, and assessing all activities conducted.
Quality Management System
That aspect of the overall system of the organization that determines and implements the quality policy; the system that includes strategic planning, allocation of resources, and other activities (e.g., planning, implementation, documentation, and assessment) pertaining to the quality system.
Quality Manual
Document specifying the quality management system of an organization.[1]
Quality System
A structured and documented framework of an organization for its planning, implementing, documenting, and assessing work performed and for carrying out required procedures and activities for ensuring satisfaction in its work processes, products, and services.
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Quality System Assessment (QSA)
A documented activity performed to verify, by examination and evaluation of objective evidence, that the required organizational elements have been developed, documented, and effectively implemented in accordance with specified requirements. Also known as Quality System Audit.
Quantitation Limit
The level above which numerical results may be obtained with a specified degree of confidence; the minimum concentration of an analyte, or category of analytes, in a specific matrix that can be identified and quantified above the method detection limit and within specified limits of precision and bias during routine analytical operating conditions.
Random Error
The unplanned deviation of an observed value from the true value that occurs produced by unpredictable and unknown sources of variation, e.g., due to fluctuations in conditions such as temperature, mechanical vibrations, reading error, etc.; also known as experimental error.
Randomization
The process of taking sample or making observations in a non-linear method so as to simulate chance.
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Random Sample
A subsection of a population selected in such a way that each unit of the population has the same chance of being selected.
Range (statistical)
The numerical difference between the minimum and maximum of a set of values.
Ranked Set Sampling
A specimen site-selection process wherein expert judgment or an auxiliary measurement method is used, in combination with simple random specimen collection, to determine which locations in the field should be selected.
Raw Data
The documentation generated during sampling and analysis which includes, but is not limited to, field notes, hardcopies of electronic data, disks, untabulated sample results, QC sample results, printouts of chromatograms, instrument outputs, and handwritten notes.
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Readiness Review
A systematic, documented assessment of the preparedness for the start-up or continued use of a facility, process, or activity typically conducted prior to initiation of a major phase of work.
Record
A completed document that provides evidence of an item or process, e.g., photographs, drawings, magnetic tape, and other data recording media.
Recovery
The act of determining whether or not the methodology measures all of the analyte contained in a sample, often expressed in percent recovered.
Reference Method
A procedure or process which is considered a standardized or commonly accepted and to which another procedure or process is compared.
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Regression Analysis
A statistical procedure used to determine the relationship between one or more independent variables and a dependent variable; a measurement of change in one variable as the result of changes in other variables.
Reliability
The ability of a system, process, or parameter to do what is expected or specified under set conditions and designated time interval without failure.
Repeatability
The degree of agreement between independent test results produced by the same analyst, using the same test method and equipment on random aliquots of the same sample within a short time period.
Replicate
A duplicate, copy, or repeat of an element, item, or process, often used to develop an average value or to assess the sources of variability and error.
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Reporting Limit
The minimum value below which data are documented as non-detected.
Representativeness
A measure of the degree to which data accurately and precisely characterize a population, parameter variations at a sampling point, a process condition, or a condition; the correspondence between the analytical result and the actual quality or condition experienced by a contaminant receptor.
Representative Sample
A subset of a population that is supposed to reflect what should occur under normal operating conditions.
Reproducibility
The precision, usually expressed as variance, which measures the variability or closeness among the results of measurements of the same sample at different laboratories by different operators.
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Sample
A single item or specimen selected from a larger population, such as any subset of a population of any medium (air, water, soil, etc.) used to characterize or make inferences regarding that population.
In acceptance sampling, one or more units of product (or a quantity of material) drawn from a lot for purposes of inspection to reach a decision regarding acceptance of the lot.[1]
Sample Size
The number of specimens units to be collected or the relative size of each specimen, volume, weight, etc.
The number of units in a sample.[1]
Sampled Population
The specimens collected or selected from a set location or locations.
Sampling and Analysis Plan (SAP)
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