Interpreting and Using Statistics in Psychological Research. Andrew N. Christopher

for will be there, but in all likelihood (i.e., probability), it will be. We can contrast heuristics with algorithms, which are step-by-step procedures that guarantee, eventually, that we will solve a problem correctly. In the grocery store example, you could walk up and down each isle looking for the toothpaste, and eventually, you would indeed find it. However, who wants to spend their time that way? Most people prefer to navigate the world as quickly and efficiently as possible, and heuristics, not algorithms, make that possible.

      Photos 1.2a and 1.2b Stairs to the basement. A killer in plain sight?

      Source: ©iStockphoto.com/danhowl

      Heuristic: mental shortcut that allows us to make decisions quickly.

      Algorithm: step-by-step procedure that guarantees a correct solution to a problem.

      So it is with making many, if not most, of our decisions in life. Last night, I made a decision to go downstairs and do laundry, and no, the risk I was taking never crossed my mind. I bet that the notion of being a victim of terrorism scares people more than being the victim of a fall despite the overwhelming odds of dying from a fall. Let’s examine why this is the case.

      Availability heuristic

      Which of these two headlines do you think will capture people’s attention more? First, “Statistics Teacher Dies Carrying Laundry Downstairs.” Or second, “Civilian Killed in Terrorist Attack.” I am betting more people will read the story that accompanies the second headline. In fact, would the first headline even make the news? I doubt it would. The availability heuristic involves estimating the frequency of some event happening, based on how easily we can think of examples of that event (Tversky & Kahneman, 1974). When there is an act of terrorism, it is much more likely to be on the news than when a person dies falling in his or her home. Perhaps the local news would make mention of a person dying in a fall, but even if that is the case, hearing about a terrorist act is more frightening to people and more likely to stick in their minds. Let’s discuss one reason we rely on the availability heuristic, and then we’ll discuss a couple of applications of it.¹

      At some point, I bet you have had to do a group project. One characteristic of a functional work group is that each member has an assigned role and responsibilities (West, Borrill, & Unsworth, 1998). Even if this task was done in your groups, did you ever get the feeling that as the project moved along, you were doing more than other members of your group? If so, there is a reason why we, at least in Western cultures, tend to think this way. How does the availability heuristic work in this situation? Because we are egocentric, we have difficulty seeing the world from other people’s perspectives. We are each fully aware of the work we are doing, how challenging that work is, the time we invested in that work, and so on. However, that information about the work other people have done is not so readily available to us; hence, it is why most people in this culture tend to overestimate their individual contribution to a group project.

      Availability heuristic: estimating the frequency of some event happening, based on how easily we can think of examples of that event.

      Egocentrism: tendency to perceive the world from our individual, unique perspective.

      Photo 1.3 An example of egocentrism, Boston style.

      Indeed, egocentrism is an important reason why we rely on the availability heuristic. It takes a lot of time and effort to perceive the world from a perspective other than our own. Take another example. In this culture, we often say, “The run rises in the morning,” and “The sun sets in the evening.” In reality, the sun does not go anywhere; we on Earth are moving, but we cannot see or feel that motion. Therefore, what is available to us is whether we can see the sun. Thanks to our egocentrism, it appears thesun is moving, but it is not. Although being egocentric is normally not a problem to our daily functioning, it can require some altering of our thinking when presented with information, especially quantitative information that may feel impersonal and that counters our perspectives. For instance, one of my best friends from high school grew up in Massachusetts before moving to Plano, Texas, where we met. A few months after he moved, his family decided to vacation in the Rio Grande Valley in South Texas. They were shocked at how long a drive it would be from Plano (about 9 hours). After all, it was all in the same state. However, states in the northeastern United States are geographically smaller than they are in the southwestern United States. So to get from one end of a state in the Northeast to the other end of that same state requires far less time than it does in Texas. What was available to my friend and his family was their perspective on the geographic size of a “state,” which varies greatly across regions of the country.

      Photo 1.4 Winning at the casino seems so easy on TV.

      Source: ©iStockphoto.com/DarrenMower

      So now that we understand why we rely on availability, let’s see it in action. Advertisers make good use of the availability heuristic in trying to persuade people to buy their products and services. For example, casinos will create commercials in which people who won money are proudly displaying their winnings, saying how much fun they had at the casino, and how it is the best place to spend a weekend, all with huge smiles on their faces.

      If someone happens to win a lot of money at the casino, why would they not be in a commercial (which they are perhaps getting paid to do on top of their gambling winnings)? If it is that easy to win money, we should all go the casino, as it seems everybody is a winner there. Of course, there is some information that is missing. That is, those commercials never show the people who lost their money gambling at that casino. And, in fact, most people have to lose money gambling as it is one way that the casinos make money to stay in business! But by only making available to viewers the people who won money, casinos make available in our minds that they exist just to hand us cash. So naturally, why would we not go there and gamble? Of course, the casinos neglect to make available the reality of gambling for most people.

      Another specific application of the availability heuristic is the framing effect, in which people are persuaded by the way information is presented rather than by the value of the information itself (Hardisty, Johnson, & Weber, 2010). Let’s take an example from a food that I tend to eat too much of: potato chips.

      Photo 1.5a and 1.5b Are baked chips really better for you?

      Let’s look at RUFFLES® Original Potato Chips (hereafter, “Original Ruffles”) and RUFFLES® Oven Baked Original Potato Chips (hereafter, “Baked Ruffles”), made by Frito-Lay® (Purchase, NY). As you might have guessed, Baked Ruffles are baked. The Original Ruffles are fried. So if one type is called “Baked” Ruffles, why not call the other type “Fried” Ruffles to signify how the chips were made? What image does “fried” make available in your mind? It is likely not one of health food. “Baked,” on the other hand, sounds like it might be healthy, so therefore it is included on that package. This is an example of the framing effect. Health-conscious consumers might not buy Original Ruffles because there is no real health value in them. However, by baking the chips instead of frying them, it does reduce the fat content, so this benefit gets advertised on the package. Original Ruffles do not advertise that they were fried on the package because most people perceive fried foods to be unhealthy.

      Framing effect: tendency to be persuaded by the way information is presented.

      You might be asking at this point whether Baked Ruffles are healthier than Original Ruffles. Let’s look at the nutritional information to see whether