The Rotterdam model can be used to estimate one form of this quantity, for which Richard Stone was the first to empirically derive a linear expenditure system. For a firm in a perfectly competitive market, this quantity is infinitely elastic. (10[1])The (10[1])Slutsky equation relates the Marshallian form of this quantity (10[1])to its (10[1])Hicksian form by accounting for the substitution and income effects. (-5[1])The cross elasticity (10[1])of this quantity measures (-5[1])its sensitivity to changes in a different good’s price. (10[1])For Veblen goods, this quantity [emphasize] increases as price increases, often due to the (10[1])value of those goods as status symbols. For 10 points, what quantity is defined as consumers’ (10[1])willingness and ability to buy a certain (10[1])good? ■END■