7.2: Opinion Dynamics

Opinions — political or otherwise — shift frequently. When asked the same or similar questions at different times, we often change our answers whether those times are months, days, hours, or even just minutes apart. Attitude change is one possible explanation for opinion change, but opinions can also vary even if the attitudes on which they are based remain constant.

The instability of opinions is rooted in human psychology. Generally, we do not store preformed opinions in our minds, ready to deploy one if someone asks. Instead, we generate opinions on the fly when they are required of us, based on pieces of information stored in our memory. This is why you can encounter totally novel decisions — whether to try an unusual food, what to tell a friend about his or her new outfit, how impressive an artistic or athletic performance was — and make snap judgments with no preparation. You won’t always be satisfied with these snap judgments, but your ability to make them at all instead of being paralyzed with indecision demonstrates that opinion formation often happens in the moment.

When people generate opinions on demand, they generally do not consider all the relevant information in their minds before reaching a conclusion. You would likely think about only a handful of reasons to approve or disapprove of the president before stating your opinion, even though you might be able to list a hundred reasons if given enough time. Your attitude toward the president may consist of many factors, but only a few will influence the opinion you render. The salience of the information in your head — how likely each piece of information is to come to mind — determines which factors you consider when forming an opinion. The more salient a factor, the more likely you are to consider it.

The salience of information in a person’s mind changes over time due to priming. Events and experiences can “prime” certain information, making it temporarily easier to recall and therefore more influential in opinion formation. This is why Americans are likely to report feeling more patriotic if they are asked in July than if they are asked in April. In July, Americans are primed by Independence Day celebrations to think about the benefits of their citizenship, whereas in April they are primed by the deadline for paying their federal income tax to think about its costs. Primes don’t necessarily change people’s attitudes, but they do change which parts of those attitudes come to mind most readily, for at least long enough to affect which opinions are expressed.

Although primes can be surprisingly effective at changing opinions almost instantaneously, it’s important to not overstate their impact. Primes tend to be most influential right when a person is first exposed to them, after which their potency declines rapidly. One reason for this phenomenon is that people are exposed to so many primes that the effect of any one prime is quickly superseded by multiple other primes, unless the initial prime is particularly powerful or repeatedly reinforced.

How opinions are solicited can influence the salience of factors in a person’s mind, thereby influencing the opinions they report. Framing is a special category of priming which stems from how questions or issues are presented. For example, supporters of abortion often refer to “reproductive rights” when describing the issue, whereas opponents of abortion often mention “the right to life.” These expressions are used specifically to frame the issue of abortion by emphasizing different factors (the rights of the mother versus the rights of the child) with the goal of making those factors more salient. Most public opinion researchers try to avoid biased framing when designing survey questions. Nevertheless, unintentional framing effects often produce noticeable effects on opinions, even when they have no lasting impact on underlying attitudes.

Primes and frames do not impact all people equally. The same prime or frame might impact one person strongly, a second weakly, and a third not at all. It is impossible to know based on a single survey response how much of a role a particular prime or frame played in shaping that response. Still, primes and frames can influence enough people to cause substantial shifts in public opinion overall. Understanding how and in what contexts opinions are solicited are asked is therefore crucial for interpreting public opinion data.