Asking Questions - The Definitive Guide To Questionnaire Design ...

ASKING QUESTIONS THAT MEASURE KNOWLEDGE 203
many public issues it is more important to know that opinion has
not yet crystallized than to force an answer. On many issues high or
low levels of knowledge can be obtained, depending on the difficulty
of the questions.
The easiest type of question is one that asks “Have you heard or
read about . . . ?” For example, a question asking “Have you heard
or read about the trouble between Israel and the Arab nations in
the Middle East?” received 97 percent “yes” answers in a 1973
Gallup Poll. When this same type of question was made more specific,
however, asking “Have you heard or read about the recent
Sinai Disengagement Pact between Egypt and Israel?” only 59 percent
of respondents answered “yes.”
Dichotomous and multiple choice questions can be somewhat
more difficult for people to answer. The questions in Figures 6.9,
which can be answered “yes” or “no,” illustrate the most common
kinds of dichotomous questions. Other examples from Gallup are
“Do you happen to know if the federal budget is balanced, that is,
does the federal government take in as much as it spends?” and
“From what you have heard or read, do you think we produce
enough oil in this country to meet our present needs, or do we have
to import some oil from other countries?” These questions are not
strictly dichotomous since a “don’t know” answer is also possible.
The “don’t know” answer is more likely to be given if a phrase such
as “Do you happen to know . . .” or “As far as you know . . .” is
included at the start of the question. Questions 2 through 11 in Figure
6.11 illustrate uses of multiple choice questions, in which the
alternatives are given to the respondents. These are, of course, more
difficult than dichotomous questions, since the possibility of guessing
the right answer is reduced. In all these questions, the answer “I
don’t know” is explicitly included to reduce guessing and to indicate
that “don’t know” answers are expected and acceptable.
More difficult still are questions that ask for details. Question 2
in Figure 6.5 and the questions in Figure 6.7 ask respondents for
minimal identification about a person or company they have heard
about. This information can include titles, reason for fame, and the