Was the Professor correct?

Recal the Professor's original claim that by the year 2060 the average white male will stand 1.93 tall?

This result is easily obtained by substitution of the year 2060 into out equation:

av.height = 0.000158 x 2060 - 1.324 = 1.93 m

Is this a valid use of the data?

There are two questions to be asked here.

  1. Are we really doing a sensible thing by EXTRAPOLATING the data we have into the future like this?

  2. Was it correct to assume that there is a linear relationship between the data points we had (as opposed to some more complicated relationship)?

We can deal with the first question quite easily: Something suspicious is definitely going on here! The reason being, that we could keep extrapolating (i.e. put even larger values for the "year" into our equation) and conclude, for example, that by the year 3000, white males will be 3.4m tall.

LESSON: Always be aware of the physical limitations of any relationship you might form. In other words, don't extrapolate the data beyond reasonable limits. If possible, when creating a relationship, sepcify the limits of the relationship; make it clear where the measured results end and the extrapolation begins.

The second question is a little trickier, so we have given it a page to itself.

Answer to the second question.
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