This post considers the evolving public opinion on two proposals: the 49er’s move to Santa Clara and the A’s move to San Jose, as well as some lessons local public officials can draw from these two cases.

The two key variables are familiarity and favorability (approval). Social Psychological theory argues that familiarity and favorability are correlated and there is substantial evidence in support of that general proposition.

Related to that is the observation that: What people know (their information) is a key determinant of voters’ attitudes. People change their opinions based on new information. Therefore, providing more information generally maintains or increases  familiarity. Providing positive information generally increases approval.

The graph, based on the two surveys, presents the net familiarity and net approval for the A’s and 49er’s moves. (Net familiarity equals the difference between the percentage familiar and the percentage unfamiliar. Net approval is the difference between the percentage approving and the percentage disapproving.) The correlation between familiarity and favorability is readily apparent. Further, it makes a good case for a solid public information campaign, even in the absence of apparent progress.

First, let’s follow the example of the 49er’s. The team’s move to Santa Clara was once dismissed. However, once the move appeared plausible and well planned, the familiarity and approval increased. More information increased both familiarity and approval.

Now in contrast, what has happened with the A’s move to San Jose? The A’s plan hasn’t progressed and there’s been little news (positive or negative). This lack of information led to a drop in familiarity and therefore, no change in approval. As a word of warning, in some cases, an information vaccum can lead to a declining net approval.

That being said, what can we expect of public opinion regarding the A’s move? If the A’s plan is a good, even plausible, one then the familiarity and approval should follow the pattern of the 49er’s. As voters receive more positive information and familiarity increases, approval should also increase.

Of course, negative news is possible. That would change the prognosis. The final proposal might be poor. Outside events could bring the move into question. Something else could cause a problem. Time—and the level and character of information–will tell how things evolve for the A’s.

Both surveys consisted of telephone interviews of likely 2010 Santa Clara County primary voters to ensure comparability.

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