-- ABCNews.com posts online ballots as a way of encouraging users to express their views and participate in our community.
These ballots, however, are not polls. They are not based on scientific, representative samples and their results are vulnerable to manipulation by individuals or groups with an interest in the outcome. They are for entertainment only.
To avoid confusion and discourage manipulation, we do not offer percentaged results of online ballots -- only vote totals. We do not refer to them as "polls" or "surveys," words that indicate the use of a representative sample. These ballots do not constitute a reliable sounding of public opinion.
Online ballots can be manipulated by orchestrated campaigns of like-minded individuals intent on stuffing the ballot box. They also can be hacked by individuals or small groups using more sophisticated techniques to overcome multiple-voting restrictions.
We have no reliable method of determining whether or not an online ballot has been manipulated. If, however, we see clear indications of manipulation we will remove the ballot from our site. Nonetheless, all online ballots are vulnerable, and evidence of manipulation may not be apparent even when it has occurred.
For some of our coverage of past problems with online ballots see articles here, here and here. For our description of the principles underlying scientific polling, see our article here, and our explanations of our survey methodology here and of sampling error here.