Fabrication of DGUs

SFBearCop wrote:

I can think of a number of reasons, none of them noble, why someone would
fabricate a DGU, starting with giving the pollster what they thought was
wanted. People do it all the time, so a friend in the public-opinion-counting
game told me thirty or more years ago.

John Briggs writes:

This would account for some false positives in the DGU surveys. It would
also be present, presumably, in NCVS responses. The question is why are the
response rates so different?

The DGU question appears quite early in Kleck`s survey. It’s not hard
for a person to guess that it is the important question and give the
interviewer what they think the interviewer wants. With the NCVS it
occurs after many other questions and without the clue of mentioning a
gun in the question.

Does the relative lack of interest the NCVS
shows in defensive behavior in general prompt false negatives and false
silences that affect its reported DGU rates?

Quite possibly. But a false positive rate of 2% gives you two
million bogus DGUs, while a false negative rate as high as 50% means
you only underestimate by a factor of two.

SFBearCop wrote:

Follow that with the need to seem more important than you are. It’s called
bragging. Most men, and a few women, don’t like to be thought lacking in the
right stuff. Of course they used a gun to deal with some humna varmint. It’s
in the traditions of our nation, of western history, of all we hold sacred!

John Briggs writes:

Certainly a factor. But would it not be more manly to use one’s bare

Perhaps. But the structure of Kleck’s survey doesn’t give you that
option. If you want to brag to Kleck’s surveyor, you have to make up
a DGU.

What we don’t know is the degree of bragging. Why don’t respondents brag to
NCVS interviewers to the same degree?

If you want to brag how you thwarted a crime to the NCVS you don’t
have to claim you used a gun. You can be more manly and say that you
used your bare hands 😉 Also, the NCVS interviews the same household
every six months over a three year period. The first interview turns
up about 50% more crime than subsequent ones. THe NCVS believes this
is caused by “telescoping” and discards the first interview. Some of
the difference may be caused by braggers who give up bragging when
they find that it doesn’t impress the NCVS interviewer.

Another reason why people might lie:

The respondent could be afraid that the interviewer is really a
criminal “casing the joint”, so she makes a DGU to make it clear that
she has a gun and is prepared to use it against any criminal that
breaks in.