Resource Type: Experiments

This response to Dan Kahan’s critique of the author’s initial study provides data from a replication study using a larger sample to demonstrate that a consensus message can indeed directly cause changes, not only in estimated scientific consensus, but also in belief that climate change is happening and human-caused, worry about climate change, and support for action. 

Much research finds that “scientific consensus messaging,” or informing people that 97% of scientists believe climate change is happening and human-caused, can change people’s minds. A landmark study in 2015 by Sander van der Linden and colleagues reports that people who heard this message believed there was a stronger scientific consensus climate change, compared to a control group who heard no message, and that this was a “gateway” belief that then caused other beliefs to change (Gateway Belief Model). However, Kahan takes another look at the data from that study and argues that this claim should be tempered. Sander van der Linden and colleagues have responded to this critique.

This article offers empirical evidence supporting a relationship between social influence and voter turnout by comparing the effectiveness of face-to-face get-out-the-vote visits by canvassers living in a voter’s local neighborhood against visits by canvassers from other neighborhoods. This study, published in 2013, looked at canvassing in Los Angeles in 2006 and attempted to discern a difference between canvassers local to the neighborhood in which they were working and those working outside where they lived. In addition, this study confirmed that low-propensity voters can be turned out to vote based on a face-to-face conversation. 

One of the seminal studies of the influence of face-to-face contact on voter turnout, this paper from 2000 by Alan Gerber and Donald Green shows that in-person contact substantial increases voter turnout, while the effect of direct mail is slight, and that of live phonecalls is nonexistent. This randomized controlled trial of 30,000 voters in Connecticut showed statistically significant effects of canvassing, results that have been replicated several times since this study was published.  The authors also claim support for their hypothesis that the long-term decline in voter turnout observed to that point was due in part to the decline in face-to-face political mobilization.             

This webinar walks through how to create digital “surround sound” around a target audience over multiple channels. It also provides an introduction to Google AdWords: what it is, how it works, and pro tips on how to use it well to promote your organizations and campaigns. Watch the recording or take a look at the slide deck. (And for another example of this technique, see slides 99 and 100 from the Lab’s campaign planning training)