Difference between revisions of "Accuracy"

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Look in your GPS manual and it will say something like “Accuracy of <15 meters”. This is it's degree of conformity to a standard i.e. within 15 meters of bulls eye. The EPE that is on your GPS however should often be as low as 4 meters. This is the degree of refinement in the performance of an operation. i.e a the uniformity of the co-ord within the aforementioned range of accuracy.
 
Look in your GPS manual and it will say something like “Accuracy of <15 meters”. This is it's degree of conformity to a standard i.e. within 15 meters of bulls eye. The EPE that is on your GPS however should often be as low as 4 meters. This is the degree of refinement in the performance of an operation. i.e a the uniformity of the co-ord within the aforementioned range of accuracy.
  
[[image:accuracy.gif]]
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{| align="center"
Accuracy
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| align="center" width="200px" | [[image:accuracy.gif]]
 
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| align="center" width="200px" | [[image:precise.gif]]
[[image:precise.gif]]
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| align="center" width="200px" | [[image:precaccu.gif]]
Precision
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|-
 
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| align="center" width="200px" | Accuracy
[[image:precaccu.gif]]
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| align="center" width="200px" | Precision
Accuracy with Precision
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| align="center" width="200px" | Accuracy with Precision  
 
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|}
  
 
References:
 
References:

Revision as of 15:09, 20 December 2005

EPE (the “Accuracy” shown on your GPS) is an estimation, rather than a measurement.

There is a difference between Accuracy and precision

To many people, accuracy and precision mean the same thing: to someone involved in measurement, the two terms should have very different meanings.

Accuracy - the degree of conformity with a standard

Precision - the degree of refinement in the performance of an operation

Look in your GPS manual and it will say something like “Accuracy of <15 meters”. This is it's degree of conformity to a standard i.e. within 15 meters of bulls eye. The EPE that is on your GPS however should often be as low as 4 meters. This is the degree of refinement in the performance of an operation. i.e a the uniformity of the co-ord within the aforementioned range of accuracy.

Accuracy.gif Precise.gif Precaccu.gif
Accuracy Precision Accuracy with Precision

References:

http://www.geoplace.com/gw/2000/1000/1000gps.asp

http://www.flatsurv.com/accuprec.htm