Avoid Arc Elasticities

Avoid the midpoint-method of calculating percentages.  Avoid arc elasticities.  In my view, these methods are a distracting waste of time that make it difficult to understand the important concept of elasticity.  I NEVER use them in the course or on exams.

Unfortunately, the midpoint method is used for arc elasticities of demand in the Minnesota and Openstax Textbooks (Ch 5, Sec 1 in both books).  For that reason, I do not suggest either section as a reference reading. If you see these methods being used in outside readings, textbooks or in review problems, please avoid reading them.  And do not memorize the arc-elasticity formula.  Memorizing complicated formulas is almost always a bad idea.