Do Mystery Callers Really Represent Customers?

Mystery calling is a specific form of mystery shopping that is often applied for evaluating customer contact services. Using data from both customers and mystery callers (MCs), we study the validity of MC data for evaluating customer-related performance measures. Controlling for characteristics of the call, we find no bias in MC’s evaluations of satisfaction and gratitude, and less positive word of mouth. Furthermore, we find that MC’s evaluations are more positive if s/he is a customer and in case of longer calls. More experienced MCs evaluate less positive. We recommend regular refreshment of the composition of the group of MCs.