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Dixon test

To use the Dixon test the ratio is calculated:
  • b = total range of measurements (here 14.1)
  • a= the distance between the part suspected of having an abnormal value and its nearest neighbour (here 8.6)
The ratio is calculated in %:
We then compare this ratio with the Dixon table:
Number of parts3510162030
Maximum ratio0.940.720.460.380.340.30
If the value is less than the maximum proposed ratio in the table then the value is not abnormal. Here a ratio of 62% per 5 parts is less than 72%. The point is thus not an abnormal value.