Persuasive Communication - How Audiences Decide. 2nd Edition

164 Understanding Rational Decision Making

Graphs

Quantitative information is often easier for audiences to comprehend when it is presented in a

graphic as opposed to a tabular or sentence format,^218 especially for those audiences with high

graph literacy.^219 Health care consumers, for example, fi nd risk/benefi t information easier to com-

prehend and more helpful to their decision making when it is presented in a graphic format

as opposed to either sentences or tables.^220 However, even a well-designed graph that highlights

task-relevant information will have little effect on comprehension if the viewer lacks the domain

expertise to interpret it.^221

Viewers can comprehend most graphs more quickly if the plot lines, bars, pie segments, and

other depictions of the data in them are labeled.^222 The use of legends or keys instead of labels

makes graph comprehension more diffi cult and poses special demands on viewers’ working mem-

ory.^223 Other impediments to graph comprehension include the use of arbitrary symbols such as

stars, ships, castles, trees,^224 or faces.^225 Positioning graphs at the end of a document instead of in

proximity to their mention can also decrease the audience’s comprehension of them.^226

Although the use of an attention-getting third dimension in charts and graphs does not neces-

sarily reduce the viewer’s accuracy or speed of making comparisons,^227 in general, two-dimensional

graphs support viewer comprehension better than three-dimensional ones.^228

Aids to Schema Activation

In order to fully comprehend and use the information in a paragraph, document, graph, image, or

presentation, the audience must fi rst activate the appropriate schema. Audiences must activate the

appropriate schema regardless of the communicator’s purpose—whether it is to inform, instruct,

entertain, or persuade the audience to make a decision. Any contextual information—such as a

title, section heading, or introductory paragraph—can help audiences activate the right schema.

The right graph or picture can also activate the appropriate schema and portray the “big picture”

at what seems like a single glance.^229

Titles

Titles not only attract attention, they also activate readers’ schemata and in doing so make text easier

to comprehend and recall.^230 In a seminal study of titles and schema activation (described in detail

on p. 121), readers were asked to make sense of an untitled paragraph. Although all the words and

individual sentences were understandable, the paragraph as a whole seemed nonsensical to the read-

ers until they were provided with its title “Washing Clothes.” The title activated the appropriate

schema for interpreting the various activities involved in washing clothes that were described in

the paragraph.^231

By activating the appropriate schema, titles help readers comprehend intersentence coherence

within paragraphs and longer passages.^232 When a title indicates the text is about a topic for

which the readers already possess the relevant background knowledge or schema, readers will even

“remember” reading content that is not actually present in the text.^233

By activating one schema as opposed to another, titles infl uence what information is recalled^234

and how that information is interpreted.^235 In other words, titles “frame” the information that

follows them. In one experiment, readers were given paragraphs that could be interpreted in two

different ways depending on the title that introduced them. For example, the same paragraph

could be interpreted as being about “the worries of a baseball team manager” or “the worries of a

glassware factory manager.” The title that introduced the paragraph determined how readers com-

prehended it by making one schema more accessible to them than the other.^236