Arc and point elasticities ◆An“ average”own- price elasticity of demand for commodity i over an interval of values for p; is an arc elasticity, usually computed by a mid-point formula Elasticity computed for a single value of p, is a point elasticityArc and Point Elasticities ◆An “average” own-price elasticity of demand for commodity i over an interval of values for pi is an arc￾elasticity, usually computed by a mid-point formula. ◆Elasticity computed for a single value of pi is a point elasticity