Despite growing prevalence of online shopping, its impacts on mobility are poorly understood. This partially results from the lack of sufficiently detailed data. In this paper we address this gap using consumer panel data, a new dataset for this context. We analyse one year long longitudinal grocery shopping purchase data from London shoppers to investigate the effects of online shopping on overall shopping activity patterns and personal trips. We characterise the temporal structure of shopping demand by means of the duration between shopping episodes using hazard-based duration models. These models have been used to study inter-shopping spells for traditional shopping in the literature, however effects of online shopping were not considered. Here, we differentiate between shopping events and shopping trips. The former refers to all types of shopping activity including both online and in-store, while the latter is restricted to physical shopping trips. Separate models were estimated for each and results suggest potential substitution effects between online and in-store in the context of grocery shopping. We find that having shopped online since the last shopping trip significantly reduces the likelihood of a physical shopping trip. We do not observe the same effect for inter-event durations. Hence, shopping online does not have a significant effect on overall shopping activity frequency, yet affects shopping trip rates. This is a key finding and suggests potential substitution between online shopping and physical trips to the store. Additional insights on which factors, including basket size and demographics, affect inter-shopping durations are also drawn.

中文翻译：

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一种基于风险的方法来模拟网上购物对互购持续时间的影响

尽管在线购物越来越流行，但人们对其对移动性的影响却知之甚少。这部分是由于缺乏足够详细的数据。在本文中，我们使用消费者面板数据来解决这一差距，这是一种针对这种情况的新数据集。我们分析了来自伦敦购物者的为期一年的纵向杂货购物购买数据，以调查在线购物对整体购物活动模式和个人旅行的影响。我们使用基于风险的持续时间模型通过购物事件之间的持续时间来表征购物需求的时间结构。这些模型已被用于研究文献中传统购物的跨购物拼写，但并未考虑在线购物的影响。在这里，我们区分购物活动和购物旅行。前者是指包括网上和店内在内的所有类型的购物活动，而后者仅限于实体购物。为每个模型估计了单独的模型，结果表明在杂货店购物的背景下，在线和店内之间存在潜在的替代效应。我们发现，自上次购物旅行以来一直在网上购物可以显着降低实体购物旅行的可能性。我们没有观察到事件间持续时间的相同效果。因此，网上购物对整体购物活动频率没有显着影响，但会影响购物旅行率。这是一个重要的发现，并表明在线购物和实体商店之间的潜在替代。关于哪些因素（包括购物篮大小和人口统计数据）的其他见解，