If you Google [relevance theory], you’ll discover this Wikipedia entry about a theory proposed by Dan Sperber and Deirdre Wilson arguing that, in any given communication situation, the listener will stop processing as soon as he or she has found meaning that fits his or her expectation of relevance. The Wikipedia entry offers the following example of this principle:
Mary: Would you like to come for a run?
Bill: I’m resting today.
We understand from this example that Bill does not want to go for a run. But that is not what he said. He only said enough for Mary to add the context-mediated information: i.e. someone who is resting doesn’t usually go for a run. The implication is that Bill doesn’t want to go for a run today.
This theory may call to mind the Gricean Maxims — indeed, Sperber and Wilson borrow heavily from Grice’s work.
But I mainly bring up relevance theory to introduce Sperber to those unfamiliar with him. My friend (and Endeca co-founder) Pete Bell recently called to my intention an article by neuroscientist Jonah Lehrer entitled “The Reason We Reason“. The article reviews the “hot hand” fallacy and then proceeds to cite a new theory by Sperber and Hugo Mercier:
Reasoning is generally seen as a means to improve knowledge and make better decisions. Much evidence, however, shows that reasoning often leads to epistemic distortions and poor decisions. This suggests rethinking the function of reasoning. Our hypothesis is that the function of reasoning is argumentative. It is to devise and evaluate arguments intended to persuade.
The full article by Mercier and Sperber runs over 17K works and is entitled “Why do humans reason? Arguments for an argumentative theory“.
As someone who has spent most of his professional life thinking about information retrieval in practical contexts, I automatically relate relevance theory to relevance in the context of information retrieval. Relevance has been a subject of intense debate in the information science community (Tefko Saracevic tells the story wonderfully). Indeed, a key reason that I created the HCIR workshop was the belief that information retrieval researchers and practitioners (i.e., search engine developers) were placing too much emphasis on an objective notion of topical relevance, and not enough focus on the user.
Mercier and Sperber’s theory offers an interesting challenge to information retrieval researchers: perhaps a user’s information need is less about arriving at the truth and more about finding confirmatory evidence to support a preconceived conclusion. If so, should we adjust our notions of relevance accordingly? Also, if we evaluate or inform search quality based on observed user behavior (such as click-through behavior), then are we already inadvertently conflating topical relevance with users’ confirmatory bias?
Many people have noted that personalization gives us the truth we want: recent examples include Robin Sloan and Matt Thompson’s EPIC 2014 and Eli Pariser’s The Filter Bubble. Despite the consensus that over-fitting information access to our personal tastes is a bad thing (perhaps even dystopian), technology seems to relentlessly push us in this direction. Moreover, some degree of personalization is clearly useful — such as prioritizing information that relates to our personal and professional interests.
Nonetheless, anyone working in the area of information seeking systems should be concerned with the question of the user’s goal in using that system. Many of us take for granted that the user’s main goal is truth seeking, and we design our systems accordingly. What can or should we do differently if the user’s main goal is not informative but persuasive? Is the user looking for an answer…or an argument?
The Noisy Channel 