Consider the data set: :0.189,\ 0.167,\ 0.187,\ 0.183,\ 0.186,\ 0.182,\ 0.181,\ 0.184,\ 0.181,\ 0.177 \, Now rearrange in increasing order: :0.167,\ 0.177,\ 0.181,\ 0.181,\ 0.182,\ 0.183,\ 0.184,\ 0.186,\ 0.187,\ 0.189 \, We hypothesize that 0.167 is an outlier. Calculate
Q: :Q=\frac{\text{gap}}{\text{range}} = \frac{0.189-0.167}=0.455. With 10 observations and at 90%
confidence,
Q = 0.455 > 0.412 =
Qtable, so we conclude 0.167 is indeed an outlier. However, at 95% confidence,
Q = 0.455 table 0.167 is not considered an outlier. McBane notes: Dixon provided related tests intended to search for more than one outlier, but they are much less frequently used than the
r10 or
Q version that is intended to eliminate a single outlier. ==Table==