Reduction (measurement)
The calculation of known physical or mathematical influences on a measured variable is referred to as the reduction of a measurement . It serves several purposes:
- the avoidance of systematic errors
- the standardization of different measurement conditions (e.g. temperature, scale differences, influences of movements, different instruments)
- uniform mathematical reference system .
Examples of such reductions are:
- generally the calibration functions of the measuring instruments
- For length measurements, the thermal expansion of the tape measure or the refractive index of the air
- in the case of angle measurements, the terrestrial or astronomical refraction , the sighting axis error and the deviation from the perpendicular
- in the case of meteorological measurements, the conversion of the air temperature and pressure measured at the location to sea level, see vertical gradient and reduction to sea level
- in gravimetry the terrain or topographical reduction
- in astronomy the reduction from observed to true or mean star locations .
See also
- Measurement , measurement technology
- Reductions in the gravity field
- Reduction of the scale in cartography