Although the characteristics that we use to think about objects or people are determined in part by their salience, individual differences in the person who is doing the judging are also important. People vary in the type of schemas that they tend to use when judging others and when thinking about themselves. One way to consider this is in terms of the cognitive accessibility of the schema. Cognitive accessibility refers to the extent to which a schema is activated in memory and thus likely to be used in information processing. Simply put, the schemas we tend to typically use are often those that are most accessible to us.
You probably know people who are football nuts (or maybe tennis or some other sport nuts). All they can talk about is football. For them, we would say that football is a highly accessible construct. Because they love football, it is important to their self-concept; they set many of their goals in terms of the sport, and they tend to think about things and people in terms of it (“If he plays or watches football, he must be okay!”). Other people have highly accessible schemas about eating healthy food, exercising, environmental issues, or really good coffee, for instance. In short, when a schema is accessible, we are likely to use it to make judgments of ourselves and others.
Although accessibility can be considered a person variable (a given idea is more highly accessible for some people than for others), accessibility can also be influenced by situational factors. When we have recently or frequently thought about a given topic, that topic becomes more accessible and is likely to influence our judgments. This is in fact a potential explanation for the results of the priming study you read about earlier—people walked slower because the concept of elderly had been primed and thus was currently highly accessible for them.
Because we rely so heavily on our schemas and attitudes, and particularly on those that are salient and accessible, we can sometimes be overly influenced by them. Imagine, for instance, that I asked you to close your eyes and determine whether there are more words in the English language that begin with the letter R or that have the letter R as the third letter. You would probably try to solve this problem by thinking of words that have each of the characteristics. It turns out that most people think there are more words that begin with R, even though there are in fact more words that have R as the third letter.
You can see that this error can occur as a result of cognitive accessibility. To answer the question, we naturally try to think of all the words that we know that begin with R and that have R in the third position. The problem is that when we do that, it is much easier to retrieve the former than the latter, because we store words by their first, not by their third, letter. We may also think that our friends are nice people because we see them primarily when they are around us (their friends). And the traffic might seem worse in our own neighborhood than we think it is in other places, in part because nearby traffic jams are more accessible for us than are traffic jams that occur somewhere else. And do you think it is more likely that you will be killed in a plane crash or in a car crash? Many people fear the former, even though the latter is much more likely: statistically, your chances of being involved in an aircraft accident are far lower than being killed in an automobile accident. In this case, the problem is that plane crashes, which are highly salient, are more easily retrieved from our memory than are car crashes, which often receive far less media coverage.
The tendency to make judgments of the frequency of an event, or the likelihood that an event will occur, on the basis of the ease with which the event can be retrieved from memory is known as the availability heuristic (Schwarz & Vaughn, 2002; Tversky & Kahneman, 1973). The idea is that things that are highly accessible (in this case, the term availability is used) come to mind easily and thus may overly influence our judgments. Thus, despite the clear facts, it may be easier to think of plane crashes than of car crashes because the former are more accessible. If so, the availability heuristic can lead to errors in judgments.
For example, as people tend to overestimate the risk of rare but dramatic events, including plane crashes and terrorist attacks, their responses to these estimations may not always be proportionate to the true risks. For instance, it has been widely documented that fewer people chose to use air travel in the aftermath of the September 11, 2001 (9/11), terrorist attacks on the World Trade Center, particularly in the United States. Correspondingly, many individuals chose other methods of travel, often electing to drive rather than fly to their destination. Statistics across all regions of the world confirm that driving is far more dangerous than flying, and this prompted the cognitive psychologist Gerd Gigerenzer to estimate how many extra deaths that the increased road traffic following 9/11 might have caused. He arrived at an estimate of around an additional 1,500 road deaths in the United States alone in the year following those terrorist attacks, which was six times the number of people killed on the airplanes on September 11, 2001 (Gigerenzer, 2006).
Another way that the cognitive accessibility of constructs can influence information processing is through their effects on processing fluency. Processing fluency refers to the ease with which we can process information in our environments. When stimuli are highly accessible, they can be quickly attended to and processed, and they therefore have a large influence on our perceptions. This influence is due, in part, to the fact that we often react positively to information that we can process quickly, and we use this positive response as a basis of judgment (Reber, Winkielman, & Schwarz, 1998; Winkielman & Cacioppo, 2001).
In one study demonstrating this effect, Norbert Schwarz and his colleagues (Schwarz et al., 1991) asked one set of college students to list six occasions when they had acted either assertively or unassertively, and asked another set of college students to list 12 such examples. Schwarz determined that for most students, it was pretty easy to list six examples but pretty hard to list 12.
The researchers then asked the participants to indicate how assertive or unassertive they actually were. You can see from Figure 2.10, “Processing Fluency,” that the ease of processing influenced judgments. The participants who had an easy time listing examples of their behavior (because they only had to list six instances) judged that they did in fact have the characteristics they were asked about (either assertive or unassertive), in comparison with the participants who had a harder time doing the task (because they had to list 12 instances). Other research has found similar effects—people rate that they ride their bicycles more often after they have been asked to recall only a few rather than many instances of doing so (Aarts & Dijksterhuis, 1999), and they hold an attitude with more confidence after being asked to generate few rather than many arguments that support it (Haddock, Rothman, Reber, & Schwarz, 1999). Sometimes less really is more!
Echoing the findings mentioned earlier in relation to schemas, we are likely to use this type of quick and “intuitive” processing, based on our feelings about how easy it is to complete a task, when we don’t have much time or energy for more in-depth processing, such as when we are under time pressure, tired, or unwilling to process the stimulus in sufficient detail. Of course, it is very adaptive to respond to stimuli quickly (Sloman, 2002; Stanovich & West, 2002; Winkielman, Schwarz, & Nowak, 2002), and it is not impossible that in at least some cases, we are better off making decisions based on our initial responses than on a more thoughtful cognitive analysis (Loewenstein, Weber, Hsee, & Welch, 2001). For instance, Dijksterhuis, Bos, Nordgren, and van Baaren (2006) found that when participants were given tasks requiring decisions that were very difficult to make on the basis of a cognitive analysis of the problem, they made better decisions when they didn’t try to analyze the details carefully but simply relied on their intuitions.
In sum, people are influenced not only by the information they get but on how they get it. We are more highly influenced by things that are salient and accessible and thus easily attended to, remembered, and processed. On the other hand, information that is harder to access from memory, is less likely to be attended to, or takes more effort to consider is less likely to be used in our judgments, even if this information is statistically more informative.