Polling Pot, Ctd

Nate Silver contemplates the differences between live operator and automated polls:

The original Bradley Effect, named for former Los Angeles mayor Tom Bradley, occurs when respondents in surveys are asked about socially desirable behaviors, such as being free from racial prejudice. Although the racial version of Bradley effect itself is probably a thing of the past,social desirability bias may manifest itself in other ways. Automatedpolls have sometimes shown relatively lower levels...