Relative to (instead of) Absolute

Patterns of Analysis: Prefer Relative to (instead of) Absolute

A number without context does not mean much. - Absolute

A number compared to another is already meaning something - Relative

A trend is a “relative” calculation, example: traffic in the site has grown 10% last month - this is doing the relative comparison of the absolute numbers of 2 months. The absolute numbers alone give less insight.

Another advantage is with sampling, notice that in example above, “growth is 10%” could have be calculated over a sample or on absolute value, on occasion we in fact don’t have absolute values available to use.

Working with samples
In general when working with sampled data is better to keep calculations in the relative world, and avoid when possible projecting to the absolute total number. 

This is especially important when we have doubts on the accuracy of the sampling, i.e 10% sampling could be more like 8% for example.