Consumers Make Different Inferences and Choices When Product Uncertainty Is Attributed to Forgetting Rather than Ignorance

When a consumer realizes that information relevant to a consumption decision is missing, such uncertainty can be attributed to ignorance (i.e., the information has never been observed and is unknown) or to memory failure (i.e., the information has been observed and is forgotten). Although research has examined inferences about unknown attributes, no prior work has examined inferences about forgotten attributes. Across six experiments in the lab and in the field, we find that when uncertainty is attributed to ignorance, consumers often make inferences about unknown attributes based on existing correlational evidence (e.g., a brand comparison sheet that could indicate a positive or negative correlation between the unknown attribute and observable attributes). However, when uncertainty is attributed to memory failure, consumers tend to ignore such existing correlational evidence and instead make inferences about forgotten attributes that tend to be positively correlated with known attributes. This process occurs partly because when consumers believe that an attribute was forgotten, they falsely retrieve an impression about the attribute that tends to be consistent with their overall product evaluation. Overall, believing that an attribute is forgotten and believing that it is unknown can lead to opposite inferences and choices.