"It Bears Repeating"

Carl Bialik, the Wall Street "Journal's Numbers Guy," warns
once again an online survey of online activity:

Would you be willing to give up online access for a
week? Then you might not be the most likely person to answer an online survey
(or to read this blog post, for that matter).

Yet a Web survey was the basis for articles by Reuters,
the New
York Post and InformationWeek
claiming that 28% of Americans have let the Internet cut into time they spend
with friends and 20% have cut back on sex to spend more time online. Just 20%
of respondents said they could go without Web access for a week or more.

I've said
this
before,
but it bears repeating: The people who answer online surveys aren't likely to
be representative of Americans when it comes to online behavior. They've found
or been found by survey companies, they've signed up to receive emails
announcing new surveys and they are among the first to respond to those emails
by filling out the surveys. Those are characteristics of people likely to use
the Web more regularly and devotedly than the average American.

I've seconded Carl on this point before.
The full
post has more details and reactions from the company that conducted the
survey.