A field experiment on expert- versus social-based cues on dish selection in a restaurant

This field experiment explored whether and to what extent claims about expert recommendations (i.e., those of the chef) and recommendations from other restaurant guests influenced customers' food choices in a restaurant. The menu in the study consisted entirely of vegetarian dishes, two of which were selected to be emphasised either as “Chef's choice” or as “Guests' choice” on the menu, thereby providing expert-based and social-based cues suggesting one of the dishes at different study time points. The selected dishes were a vegetarian version of a conventional Swedish meat dish (a plant-based patty) and a nonconventional dish (lentils with “zero-waste” pesto). Over four weeks, the restaurant's sales data were collected, and customers were invited to participate in a voluntary survey. This survey gathered information regarding sociodemographic characteristics and more details about the dish selection, including subjective ratings of dish liking and overall meal satisfaction. A total of 1540 dishes were sold, and 524 customers participated in the survey. The plant-based patty was the most popular choice across all weeks, and the “Chef's choice” had no additive effect, suggesting its high stability in popularity. Labelling a less popular dish (lentils with “zero-waste” pesto) with “Chef's choice” had a positive impact on its selection, while labelling it with “Guests' choice” made no difference. These results suggest that in the absence of meat options, some customers appear to transfer the concept of a meat-centric dish to a similar vegetarian dish (in this case, a plant-based patty), whereas a less popular dish with no resemblance to a conventional meat dish can become more popular when recommended by a presumable expert on the matter. However, further research is necessary to ascertain the efficacy of this effect in diverse restaurant contexts, based on designs with better possibilities to establish causality. • Effects of labelling dishes as expert or social cues were assessed in a restaurant. • A vegetarian dish mimicking a conventional meat dish was always the most popular. • Labelling a less popular vegetarian as a "Chef's choice" increased its popularity. • Labelling the same vegetarian dish as a "Guests' choice" had no effect. • Both cues had no effect on customer liking or meal satisfaction.