Integrating dual-process and pragmatic theories for the processing of verbal and numerical food quantifiers

This thesis investigated how using a verbal or numerical quantifier format affects people’s psychological judgement and decision-making in three areas: interpretations, attention to, and evaluation of quantified information. These formats are commonly used in nutrition communication, but there is a paucity of evidence in the literature on how they each affect judgement and decision-making processes, and how this could affect current practices in applied communications. Over 14 pre-registered studies, this research drew on two previously independent theoretical frameworks, dual-process theory and pragmatic theory, to explain the differences in people’s processing of verbal and numerical quantifiers, with a specific focus on quantifiers used to convey food information. Chapter 1 gives a brief overview of the theoretical and applied literature. Chapter 2 (Experiments 1-2) discusses the substantial inter-individual variance found in interpretation of verbal nutrition quantifiers, and a general misalignment between consumer interpretations and standard guidelines. Chapters 3-4 (Experiments 3-6) show using multiple measures of processing (response time, decision performance, subjective effort, reliance on contextual information, and performance under cognitive load) that verbal quantifiers are not necessarily more intuitively processed than numerical quantifiers, but people may make better decisions quicker with numerical quantifiers. Chapter 5 (Experiment 7) shows how people’s attention to quantified attributes is greater with verbal than numerical quantifiers. Finally, Chapters 6-7 (Experiments 8-14) leverage the attribute framing effect, where positive frames (e.g., ‘energy’) are preferred to negative ones (e.g., ‘calories’), to compare dualprocess and pragmatic theories of quantifier processing. Overall, verbal quantifiers can increase the influence of informational context on a person’s decision, however the process involves both affect-driven responses and the extraction of implicit information from the communicative choices of a speaker. These findings can be applied to better frame quantifiers presented on nutrition labels such that consumers receive accurate and useful information.