accuracy
See Also: precision, uncertainty
[mathematics] The degree to which a measured value conforms to true or accepted values. Accuracy is a measure of correctness. It is distinguished from precision, which measures exactness.
[edit] Accuracy versus precision; the target analogy
High accuracy, but low precision
High precision, but low accuracy ...
GPS Accuracy
The U.S. government is committed to providing GPS to the civilian community at the performance levels specified in the GPS Standard Positioning Service (SPS) Performance Standard.
Accuracy: The measure of how close an estimate of a GPS position is to it's true location, usually in plus or minus feet.
Acquisition Time: The time it takes a GPS receiver to acquire satellite signals and then to determine it's initial position.
Accuracy improvements and cost reductions in the surveying field have both accelerated rapidly in recent years, driven by changes in work procedures that combine different instruments and techniques.
With the increasing demand for broad-scale vegetation maps for ecosystem management and conservation planning comes the need for flexible tools to assess thematic accuracy of these maps.
Accuracy - Degree of conformity with a standard, or the degree of correctness attained in a measurement. Accuracy relates to the quality of a result. If accuracy is relative, the position of a point is defined in relation to another point.
Accuracy - The difference between a measured value of a feature and its true value on the earth's surface.
Accuracy, Absolute - Accuracy determined by reference to a specified value.
accuracy, absolute The accuracy of a map in representing the geographic location of an object relative to its true location on the surface of the Earth. Absolute accuracy is based on geographic coordinates.
Accuracy 1. If applied to paper maps or map databases, degree of conformity with a standard if accepted value. Accuracy relates to the quality of a result and is distinguished from precision.
2.
Accuracy - Some applications may require great accuracy, others less so. How important is accuracy to your application?
Accuracy. The accuracy requirement for intelligence and signal elements is similar to the accuracy expressed by FA and ADA. In many cases, intelligence and signal units can use the SCPs established for FA and ADA.
Frequency and timeliness.
Accuracy
The closeness or nearness of the measurements to the true or actual value of the quantity being measured. Usually represented as a percentile.
Accuracy
A measure of how close an estimate of a GPS position is to the true location.
Acquisition Time
The time it takes a GPS receiver to acquire satellite signals and determine the initial position.
Accuracy
GIS has simplified the process of information extraction and communication. Combining or integrating various data sets has become possible. However, this has created the possibilities of integrating irrelevant or inconsistent data.
Accuracy - "The closeness of observations, computations or estimates to the true value as accepted as being true.
Accuracy: Closeness of results of observations, computations, or estimation of spatial features to their true value of position.
ACCURACY
The NATO STANAG 2215 Edition 5 accuracy rating for the NTS map sheet.
Horizontal Accuracy ...
Accuracy
For civilian use, the Air Force degrades the signal to an accuracy of 60m. This low level of accuracy can be overcome by using differential GPS.
Differential GPS ...
Accuracy
Digital orthophoto quadrangles and quarter-quadrangles must meet horizontal National Map Accuracy Standards (NMAS) at 1:24,000 scale and 1:12,000 scale, respectively.
Accuracy
The process of address matching and geocoding involves many variables that affect the accuracy of the results. Below is a partial list of potential sources of inaccuracy.
Accuracy Requirement
Statement of how accurate the desired results must be to support a particular application.
Accuracy Standards ...
GPS Accuracy
The accuracy of a position determined with GPS depends on the type of receiver. Most hand-held GPS units have about 10-20 meter accuracy.
Map Accuracy: A measure of the maximum errors permitted in horizontal positions and elevations shown on maps.
High Accuracy Reference Network (HARN) or High Precision Geodetic Network (HPGN) ...
[edit] Accuracy and error sources
Sources of User Equivalent Range Errors (UERE) Source Effect
Ionospheric effects
± 5 meter ...
Accuracy Assessment
Of course, in the real world many classes or features are not homogeneous, that is made of one material and formed in one definitive shape. Consider the class "field".
Accuracy - The degree to which a measurement approximates the true value of the object being measured. See also Error, Precision and Uncertainty.
ActiveX control - See Object linking and embedding (OLE).
accuracy
The degree to which a measured value conforms to true or accepted values. Accuracy is a measure of correctness. It is distinguished from precision, which measures exactness.
Accuracy
Clarity
Understandability
Improve efficiency of day to day work
Make the work invigorating and satisfying for all team members (overcome tedium)
Reduce re-work
Reduce down time due to scheduling problems ...
Accuracy of figures used
the spheroid is still an approximation to the actual shape ...
The accuracy obtained from this method depends on the duration of the observations, ...
The accuracy of interactive measurements of length is limited. A high-resolution video monitor rarely is more than 2000 pixels across; 1000 pixels is more typical.
The accuracy of the 10 °C warmest-month line as the start of the polar climates has also been questioned; Otto Nordenskiöld, for example, devised an alternate formula: W = 9 - 0.
The accuracy of fixes from the same equipment varies through time as the relative positions of satellites and receiver change.
Data Accuracy and Quality
The quality of data sources for GIS processing is becoming an ever increasing concern among GIS application specialists.
High-accuracy DEM Draped Images
ACD
Aeronautical Charting Division (C&GS) ...
Error, Accuracy, and Precision by Kenneth E. Foote and Donald J. Huebner -- Lecture notes developed for the Geographer's Craft project.
Design Accuracy
PowerRebar greatly improves the accuracy of concrete detailing, with routines that address virtually any regular or irregular reinforcement arrangement.
Digital accuracy shall be evaluated by proof plotting the digital data to the base at the same scale as the manuscript and overlaying the data to the original map.
Increase accuracy of geographic information.
Improve currency of business data.
Boost productivity of mobile field-workers.
Ensure accurate decisions with advanced spatial analysis.
Fit seamlessly into enterprise environment.
relative accuracy The degree to which map features are shown with the correct distances and directions from each other.
Attribute Accuracy:
Attribute Accuracy Report:
The data represent boundaries used for enumeration in the 2000 Census.
To verify the accuracy of our interpretations of the satellite data, we visit the imaged sites.
In Canada, lower accuracy networks (secondary control) were brought into the system over the next several years, thereby completing the NAD83 network.
121 a determination of geographic attributes judged to be of higher accuracy; usually applied to a 'point' classified into a land use/land cover category. H
'heads-up' digitizing p.
The accuracy of spatial databases. Taylor and Francis, London, U.K. 290pp. GOODENOUGH, D. G., M. GOLDBERG, G. PLUNKETT, AND J. ZELEK. 1987. An expert system for remote sensing. IEEE Trans. Geoscience Remote Sens. GE-25:349-359. GOSSELINK, J. G.
This ranges from checking accuracy when you first collect an address to many years later when the address may have changed. See our Address Management Guide for more information.
accuracy Source: OpenGIS Guide The degree to which information on a map or in a digital database matches true or accepted values. Accuracy pertains to the quality of data and the number of errors contained in a dataset or map.
single precision Refers to a level of coordinate accuracy based on the number of significant digits that can be stored for each coordinate.
Definitions Provided By: Maps for America - Third Edition accuracy Degree of conformity with a standard.
accuracy Degree of conformity with a standard. Accuracy relates to the quality of a result and is distinguished from precision which relates to the quality of the operation by which the result is obtained.
We have found our relative DEMs to have a decent vertical accuracy; some do not have good horizontal accuracy, which is due to the accuracy of the satellite ephemeris data (used to geocode the DEM).
kappa - Calculate error matrix and kappa parameter for accuracy assessment of classification result.
KEYWORDS
raster
SYNOPSIS
r.kappa
r.kappa help
r.
Another major drawback of this method is its low accuracy. The accuracy of manual digitizing merely depends on how accurate the hardcopy map is duplicated on a computer by hand.
The size of cells in a tessellated data structure is selected on the basis of the data accuracy and the resolution needed by the user. There is no explicit coding of geographic coordinates required since that is implicit in the layout of the cells.
Recently the spatial informatics is present in all categories of resolution and accuracy, the same software can be used for the cadastre, utilities, administration or environmental projects.
However, because the accuracy of the fourth decimal place is often uncertain, decimal degree coordinates are often rounded to three decimal places. This results in an accuracy of ± 364.8 feet (111.2 m).
Increasing demands for mapped data focused attention on data availability, accuracy and standards, as well as data structure issues.
Although UTM has better positional accuracy and is the most commonly accepted mapping standard world-wide, it divides the earth into six-degree zones of longitude. BC includes five of these zones, or separated projections.
 See also: Information, GIS, Location, Analysis, Area
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