A non-linear change is a change that is not based on a simple proportional
relationship between cause and effect. Therefore, such changes are often abrupt,
unexpected, and difficult to predict.
Source: GreenFacts
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A relationship or process in which a small change in the value of a driver
(i.e., an independent variable) produces a disproportionate change in the
outcome (i.e., the dependent variable).
Relationships where there is a sudden discontinuity or change in rate are
sometimes referred to as abrupt and often form the basis of thresholds. In loose
terms, they may lead to unexpected outcomes or “surprises”.
