Coffee Snobs who Refuse to Drink Instant!

An early example here of income elasticity of demand here as the Telegraph reports on the decline in the demand for instant coffee and a corresponding increase in the demand for ground coffee and coffee pods of the types beloved by owners of Nexpresso machines.

Of course, it isn't just an income effect, to isolate this you'd need to strip out the effect of changing tastes, and other variables.

Now that's what I'd call a good example of evaluation - and, indeed, past exam essay questions have asked about elasticity and wanted candidates to discuss the limitations of elasticity data.