Heuristics and Biases in Audience Decision Making 209In contrast, intuitive-mode processing activates the amygdala, the ventromedial prefrontal cortex
(vmPFC), and lateral regions of the temporal lobe. These regions have been linked to associa-
tive learning and thus to the implicit processes of the intuitive mode.^3 Although a component of
intuitive-mode processing, the vmPFC is also essential to many aspects of rational-mode processing,
especially to the information acquisition and integration steps in our model of audience decision
making.
When audiences make intuitive decisions, they are said to be using shortcuts to decision makingor heuristics. For example, when audiences decide that a person must be a librarian simply because
the person is dressed like a librarian, they are said to be using the representativeness heuristic. The
person’s appearance is representative or stereotypical of a librarian’s. When audiences decide that a
house must be worth about $250,000 just because the fi rst price they encounter is $250,000, they
are said to be using the anchoring heuristic. The fi rst price anchors or fi xes the audience’s estimate
of the value at $250,000.
Any information may be used either heuristically or nonheuristically. Deciding some-one is a librarian based on their appearance alone exemplifi es using information about their
appearance heuristically. Deciding someone is a librarian based on their appearance as well
as all of the other relevant information available exemplifi es using the same information in a
nonheuristic way.
Although each individual heuristic describes a different rule by which the intuitive mode oper-ates, all heuristics derive their persuasive power or intuitive appeal from the subjective ease of using
them, or how fl uently the information is processed. Decisions based on processing information
heuristically feel right simply because they are easy and effortless to make. When audiences use
heuristics to make decisions, they give more weight to and have more confi dence in information
that is easy to process, even when that information is irrelevant to the decision. Audiences also tend
to associate positive emotions with, and like, information that is easy to process.^4 Consequently, the
easier information is to process, the more it will be liked,^5 and the more heavily it will be weighted.
At the same time, audiences may dislike and give little or no weight to relevant information that is
hard to process.
Heuristics serve the audience well in many situations and may lead them to make satis-factory decisions based on what amounts to informed guesses. In some cases, the audience’s
subjective feelings are the most relevant information for decision making, as is the case with
judgments of liking.^6 More often, according to normative theory at least, the audience’s sub-
jective experiences of processing information, or feelings, should have no bearing on their
decisions at all.
The use of heuristics can lead audiences to systematically distort the steps normative theory pre-scribes and thus to make biased decisions. For example, when audiences use the representativeness
heuristic to make decisions they simultaneously neglect to consider other relevant information such
as base-rate information (the odds of something being true) or information about the size of the
sample studied (four doctors or 4,000?)—information needed to make a rational and statistically
meaningful decision.
The audience’s use of heuristics and their susceptibility to the resulting biases are predictable.Most audience members will use the same heuristic when processing the same information
and their decisions will deviate from normative theory in the same way.^7 For example, the
moment the prices of securities reach their peak is the time most unsophisticated investors
buy them. Instead of buying low and selling high, most inexperienced investors use the infor-
mation about high stock prices heuristically and proceed to buy high, only to sell low when
prices hit bottom.