March 14, 2006 (4:30pm) / 21
After little more than 24 hours, NARAL Pro-Choice America pulled the ad from the air.
13
By then, it had played 200 times—almost entirely in the small television markets of Maine and
Rhode Island, the home states of senators whom the organization hoped to sway (Nielsen Media
5.1
Participants, Design, and Procedure
450 adult American citizens were recruited from two pools of participants—one maintained by
Survey Sampling International, the other by a large private university—to participate in a “study
of social attitudes.”
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At the beginning of the experiment, all read a passage explaining what
the Supreme Court is, that John Roberts had been nominated to fill a vacancy, that Roberts had
argued the Bush administration’s position in Bray, and that six Justices had sided with him.
Treatment-group subjects were then asked to read a transcript of the ad. Near the end
of the experiment, they were informed that NARAL had withdrawn the ad. They were also told
about criticisms of the ad by two people: Walter Dellinger, identified as “an ally of the group
that aired the ad and an important attorney in the Clinton administration,” and Arlen Specter,
identified as “a Republican senator and supporter of abortion rights.” These criticisms introduced
no new material information about the ad. Instead, they repeated the information that had been
provided at the beginning of the experiment. The success of randomization was gauged by
testing it against the subjects’ self-reported party identification; using a chi-square test, the null
hypothesis of independence cannot be rejected (p = .49).
At the end of the experiment, subjects were debriefed as in the previous experiment and
given links to a Factcheck.org criticism of the NARAL ad and to the NARAL rebuttal of that
criticism.
13
Although the ad was released on August 8 (Keenan 2005), it apparently did not begin airing until August 10
14
Most of the questions in the study were about issues unrelated to the experiment. Subjects were also told that
“no knowledge of politics or interest in politics is necessary,” and the open-ended comments that many made at the
end of the experiment provide no indication that they were unusually knowledgeable or interested.
Convention