This article makes deep research and analysis to effect of capacitance transmitter probe shape and overall dimen 'sions on sensing accuracy as well as errors of measured components on the probe.

Other unanswered questions are whether the nose is the only part of the body affected by odours, and how smells can be measured objectively given the nonphysical components.

That makes sense because components don't need to be measured again once you define the measurements explicitly.