I think you might be getting downvoted for stating it so baldly. IQ scores reflect the place of a particular person relative to the population rather than a si

I think you might be getting downvoted for stating it so baldly. IQ scores reflect the place of a particular person relative to the population rather than a simple score derived from performance. You may mean that IQ doesn't work like decibels, which are intended for the invariant expression of relative loudness. It's a complicated area and I don't think "additive" quite captures the property that you are saying IQ doesn't have...