Abstract: There exists a spillover effect but not substitution effect between parent movie and its sequels. However, extant multi-generation diffusion models have mainly taken substitution effect into account, so they are not suitable for sequels. In order to forecast market potential and daily demand of sequels more accurately, this paper proposes a demand diffusion model for sequels integrating Bass model with three-stage process model. The proposed model is tested by using related data of sequels which were released during the period from 2011 to 2016 in China. The empirical results show that, 1)a spillover effect of parent movie, characteristic gap between two generations of movies, and market expansion significantly affect market potential of the sequel; 2)there is significant seasonality in the process of movie demand diffusion; 3)the proposed model delivers better overall performance than Marshall model and SBM both in terms of model fit and forecasting performance. Therefore, the proposed model is not only more suitable for predicting the demand diffusion of sequels, but also extends multi-generation diffusion models’ applicability range to short-life-cycle experience goods without a substitution effect.

Key words: sequel, spillover effect, demand diffusion, bass model, three-stage process model, forecasting

摘要： 续集电影与母电影之间存在品牌溢出效应但不存在替代效应。现有多代扩散模型主要考虑替代效应,难以适用于续集电影。构建了一个融合Bass模型和三阶段过程模型的续集电影需求扩散模型,以预测续集电影的市场潜量和上映期间每日需求量。以2011年至2016年国内上映的续集电影相关数据对模型进行了验证,并与Marshall模型和SBM进行了比较。结果表明1)母电影品牌溢出效应、两代电影特征差距和市场扩张显著影响续集电影的市场潜量;2)电影需求过程存在显著的季节性波动;3)所建模型在拟合优度和预测精度方面均优于两个对比模型。所建模型一方面更适用于预测续集电影的需求扩散,另一方面研究对象拓展至不存在替代效应的多代短生命周期体验品,考虑了多代产品品牌溢出效应,是对已有多代扩散模型的补充。

关键词: 续集电影, 品牌溢出效应, 需求扩散, Bass模型, 三阶段过程模型, 预测