extrapolation

n. act of guessing or inferring

In mathematics, extrapolation is the process of constructing new data points outside a discrete set of known data points. It is similar to the process of interpolation, which constructs new points between known points, but its results are often less meaningful, and are subject to greater uncertainty.
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n. extrapolation, act of guessing or inferring

n. extrapolation, act of guessing or inferring

using historical data to try to determine what will happen in the future.