Marketers are interested in the loyalty of their customer base. Increasingly this includes examining behavioural loyalty inferred from the frequency or weight of purchase. A typical approach is to divide the customer base into arbitrary segments based on weight of purchase and then attempt to move customers from lighter to heavier segments, rather than have them reduce purchasing or cease buying altogether. Effects can be monitored by examining how purchasing by groups of individuals evolves over successive periods. However, much of the flow between segments represents random fluctuations in period-to-period purchasing rather than true change to underlying loyalty. Accurate analysis requires true change to be separated from these stochastic changes, for example through benchmarks derived from conditional trend analysis (CTA). While CTA considers the two-period case, it provides no guidance for changes seen across three-periods. The three-period case is nonetheless regularly reported by panel companies and relied on by managers. We therefore develop the three-period CTA, using a tri-variate NBD, to allow the analysis of buyer flow across three successive periods. We provide an empirical illustration and demonstrate fresh insights into the evolution of consumer loyalty. The findings allay oft-raised concerns about supposedly ‘lost’ buyers, as perceived customer loss is often simply regression to the mean of the buying rates. Accordingly, the three-period CTA shows predictable proportions of buyers who move between different buying-weight segments, including first-year buyers who were apparently ‘lost’ in the second year but return to buy the brand in the third year.

中文翻译：

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扩展条件趋势分析：使用三变量 NBD 模型预测三期买家流量

营销人员对其客户群的忠诚度感兴趣。这越来越多地包括检查从购买频率或重量推断出的行为忠诚度。一种典型的方法是根据购买的重量将客户群划分为任意细分市场，然后尝试将客户从较轻的细分市场转移到较重的细分市场，而不是让他们减少购买或完全停止购买。可以通过检查个人群体的购买在连续时期内如何演变来监测效果。然而，细分市场之间的大部分流量代表了期间购买的随机波动，而不是潜在忠诚度的真正变化。准确的分析需要将真实的变化与这些随机变化区分开来，例如通过从条件趋势分析 (CTA) 得出的基准。虽然 CTA 考虑了两个时期的情况，但它没有为三个时期的变化提供指导。尽管如此，这三个时期的案例还是经常被专家组公司报告，并为经理人所依赖。因此，我们使用三变量 NBD 开发了三期 CTA，以便分析三个连续时期的买家流量。我们提供了一个实证说明，并展示了对消费者忠诚度演变的新见解。调查结果减轻了人们对所谓“流失”买家的担忧，因为感知到的客户流失通常只是回归到购买率的平均值。因此，三期 CTA 显示了在不同购买权重段之间移动的购买者的可预测比例，包括在第二年明显“迷失”但在第三年返回购买品牌的第一年购买者。