Basic Principles of GPS. Mathias Lemmens EU GIS/Mapping Advisor Abuja 4 th August 2005. Contents. Introduction GPS as a surveying tool Methods of Observation Accuracy Aspects Sources of GPS Error. Global Positioning System (GPS).
EU GIS/Mapping Advisor
Abuja 4th August 2005
Positioning by using one Receiver
The width of the function represents the uncertainty. When a coordinate is normally distributed, the 1-s interval to both sides about the mean (m) contains about 68% of the samples, and 95% of the samples (in yellow) will lie within the interval [-1.96s, 1.96s] about the mean
Accuracy and precision are often used interchangeably; precision refers to only the spread, no matter the bias, whereas accuracy both spread and bias includes
Right, the precision of the observable in dark-blue and the one in light-blue is the same, but the latter has been biased due to for instance a remaining systematic effect.
In the absence of biases (Left) precision and accuracy can be used synonymously.