Those Offering Opinions Are Better Remembered Than Those Uttering Facts

And recall of the source affects how we interpret information — and how we might act upon it

Decision-making often involves recalling pertinent information we’ve previously come across. We buy the olive oil from the compelling ad we’ve seen, or on the recommendation of the foodie influencer we follow or because some legacy media did a thorough analysis and ranked the tastiest or the best value.

Past research has established that being able to recall the source of information plays an important role in the interpretation of recalled information and the course of our decision-making. Yet we often struggle to correctly remember the source of a given piece of information. An online survey by IESE Business School’s Daniel J. Mirny and UCLA Anderson’s Stephen A. Spiller found that more than 90% of participants have experienced a “source memory” failure, and nearly three-quarters said it was frustrating. 

Marketers, public health officials and political strategists may share that frustration, as any hiccup in correct recall of who told you something can impact the decision-making process.

Who Said That?

In a paper forthcoming in Journal of Consumer Research, Mirny and Spiller offer evidence that one way to strengthen “source memory” may be to deliver the initial information — even a bona fide fact — wrapped as an opinion.

Across 13 experiments involving more than 7,500 participants, they find that we are better at recalling who shared an opinion than who shared a fact. 

An ad that crows about a top-rated olive oil doesn’t have quite the same recall mojo as an ad in which an influencer or spokesperson tells you they think it’s the most delicious olive oil.

This observation builds on other research which established that the initial uptake of information is key to being able to recall the source at a later date. During this crucial “encoding” stage, the sharing of an opinion seems to serve as more encoding glue.

The potential for this mechanism to contribute to the absorption of misinformation is beyond the scope of this research, but Mirny and Spiller offer a framework for understanding how opinions, regardless of their veracity, can be influential.

A Matter of Opinion

The series of online experiments followed a similar approach. During the initial encoding stage, participants viewed a series of AI-generated people (sources), with each source expressing two facts and two opinions. Then the study participants were run through a diversionary exercise to give the new information time to settle in their heads. 

The final step was the crux of the research: testing recall of who said what. Participants were shown the series of statements (facts and opinions) and asked to identify which source shared this information, choosing from a lineup of sources that included the original set and a bunch of decoys not previously viewed.

In one experiment, more than 400 participants read reviews for Airbnb listings in New York City from six sources. Each source made two factual claims (e.g., the room had black curtains) and expressed two opinions (e.g.,the room had ugly curtains). In the recall stage of the experiment, participants were asked to match the claim to the original source from a panel that included the original sources and a bunch of decoys. Participants correctly identified the source for 43% of the opinions, compared with 40% of the facts. 

In a similar online experiment, participants were shown a series of sources and their review of a book. The reviews were fact based (e.g., The book is about X) or opinion (e.g., The themes are profound, and the writing is beautiful). Once again, opinions spurred more correct recall of who delivered the review (37%) than did a factual statement (33%).

The research also suggests a downstream impact of this main finding. In another experiment, participants were more apt to seek out the advice of a source who had expressed an opinion versus one who expressed a fact.

Expertise Doesn’t Help

Mirny and Spiller find that expertise doesn’t necessarily make a source more memorable. 

The researchers created a fictional disease and then had participants read a series of facts and opinions about the disease, both from a layperson and a source identified as a doctor. Once again, recall of sources of opinions were more successful than recall of sources who stated a fact, but there was basically no better recall between hearing that opinion from a layperson versus the expert doctor.

Interestingly, participants were more likely to incorrectly attribute a fact to an expert even when it came from a layperson. While this suggests that there is trust in expertise, it also shows that facts may inappropriately accumulate credibility when people misremember their sources. 

While opinions are a more potent influence on source recall and advice seeking, the researchers also measured how well (or not) participants were able to correctly recall the actual information they were presented with. Across the same experiments, there was no meaningful difference in correct information recall based on whether the source shared an opinion or fact. But remembering the source is an important component of information recall, and that’s where opinions matter more.