i don't know i like that he walks in you know and he's got this little gift and how'd you pay for it credit  he you know said whipped out my little card
I like that he brought a gift.
The exponent of Pb in Equation (1), then, is not a traditional elasticity; rather, it is an elasticity for changes in own-price when the discount remains unchanged, referred to in this paper as a no-shift elasticity.