“…However, after some time period the effectiveness of this advertising effort starts to decline and reaches zero at time (L + 1). As in previous generic dairy product research, we model this behavior as a polynomial distributed lag (PDL), with end-point restrictions equal to zero (e.g., Lenz, Kaiser and Chung 1998;Kaiser 2000). In general notation, the total advertising effect on demand at time t using a PDL parametric structure with end-point restrictions can be written as: (14) where: β i = λ 0 + λ 1 i + λ 2 i 2 and β -1 = β L + 1 = 0 TADV t = the total advertising effect at time t accounting for the distributed lag effects ADV t-i = advertising expenditure at time t-i L = the total lag length λ 0 , λ 1 , λ 2 = PDL parameters to estimate.…”