[Infowarrior] - Fear and the Availability Heuristic

[Richard Forno]

(c/o Schneierblog)

Mass Murder is Nothing to Fear
By Joshua D. Foster on March 16, 2009 - 2:14pm in The Narcissus in All  
of Us

http://blogs.psychologytoday.com/blog/the-narcissus-in-all-us/200903/mass-murder-is-nothing-fear

Two terrible incidents of violence occurred last week. Michael  
McLendon went on a killing rampage in Alabama that took the lives of  
10 people before he killed himself. Half a world away in Germany, at  
about the same time, Tim Kretschmer attacked a school and murdered 15  
people before killing himself. All told, 27 people died in these two  
incidents of mass murder.

The news media in the United States has spent enormous amounts of time  
covering both incidents. We have not watched the German media, but it  
too has probably focused a lot of attention on the two incidents. It  
is probably safe to assume that news watchers in both countries have  
received a healthy dose of mass murder during the past several days.

It will be interesting to see what results from these two incidents.  
To the extent that the past is prologue, we should expect to see  
plenty of public fear and extreme reactions from officials and  
politicians. Both can be traced, at least to some degree, to a  
cognitive shortcut called the availability heuristic.

We use the availability heuristic to estimate the frequency of  
specific events. For example, how often are people killed by mass  
murderers? Because higher frequency events are more likely to occur at  
any given moment, we also use the availability heuristic to estimate  
the probability that events will occur. For example, what is the  
probability that I will be killed by a mass murderer tomorrow?

We are especially reliant upon the availability heuristic when we do  
not have solid evidence from which to base our estimates. For example,  
what is the probability that the next plane you fly on will crash? The  
true probability of any particular plane crashing depends on a huge  
number of factors, most of which you're not aware of and/or don't have  
reliable data on. What type of plane is it? What time of day is the  
flight? What is the weather like? What is the safety history of this  
particular plane? When was the last time the plane was examined for  
problems? Who did the examination and how thorough was it? Who is  
flying the plane? How much sleep did they get last night? How old are  
they? Are they taking any medications? You get the idea.

The chances are excellent that you do not have access to all or even  
most of the information needed to make accurate estimates for just  
about anything. Indeed, you probably have little or no data from which  
to base your estimate. Well, that's not exactly true. In fact, there  
is one piece that evidence that you always have access to: your  
memory. Specifically, how easily can you recall previous incidents of  
the event in question? The easier time we have recalling prior  
incidents, the greater probability the event has of occurring - at  
least as far as our minds are concerned. In a nutshell, this is the  
availability heuristic.

Of course, any rational person understands that this method of  
estimation is flawed. Just because you happened to see a clown get run  
over by a dump truck yesterday and you can now easily recall this  
event, this doesn't mean that this sort of thing happens all of the  
time. Likewise, just because a plane crashed recently or two mass  
murders occurred last week, this doesn't make these events any more  
likely either. Nevertheless, studies on the availability heuristic  
consistently show that we estimate the probability of events occurring  
based in large part on how easily these events come to mind.

As this relates to the recent mass murders, it is likely that people  
will become, at least for a time, more fearful that they or someone  
they know will be the victims of the next shooting incident.  
Politicians, whose jobs depend upon being in tune with the concerns of  
their constituents, and who are likely themselves to overestimate the  
likelihood of the next mass murderer coming to their towns, will  
probably introduce heavy-handed policies, such as banning literature  
that might incite the next perpetrator (police in Alabama discovered a  
stash of videos in the home of the gunman that instructed how to, for  
example, shoot from a moving vehicle). While these interventions will  
likely have little to no effect on future occurrences of mass murder,  
they will make people feel like something is being done to protect  
them from the boogeyman that now seems certain to live in their  
neighborhood.

Although there are many problems associated with the availability  
heuristic, perhaps the most concerning one is that it often leads  
people to lose sight of life's real dangers. Psychologist Gerd  
Gigerenzer, for example, conducted a fascinating study that showed in  
the months following September 11, 2001, Americans were less likely to  
travel by air and more likely to instead travel by car. While it is  
understandable why Americans would have been fearful of air travel  
following the incredibly high profile attacks on New York and  
Washington, the unfortunate result is that Americans died on the  
highways at alarming rates following 9/11. This is because highway  
travel is far more dangerous than air travel. More than 40,000  
Americans are killed every year on America's roads. Fewer than 1,000  
people die in airplane accidents, and even fewer people are killed  
aboard commercial airlines. The bottom line is that being a passenger  
on a plane being flown by trained professionals who are being guided  
by a team of professionals (i.e., air traffic control) is much safer  
than driving your own car on streets surrounded by other amateur  
drivers who may or may not follow the rules of the road (and whose  
cars may or may not be fit to drive). Nevertheless, I (JF) almost  
always worry that my plane will crash, but I rarely even consider the  
dangers of driving - and I teach the availability heuristic every  
semester! It just shows how powerful this cognitive shortcut really is.

Back to the killings in Alabama and Germany...The probability that any  
of us or anyone we know will ever become the victim of mass murder is  
almost too low to imagine. If we focus too many resources on trying to  
prevent this from ever happening again, we will likely expose  
ourselves to more mundane but much higher probability dangers, such as  
accidental shootings (which take far more lives than all of the mass  
murders put together). And this goes for anything whose probability is  
influenced by the availability heuristic (which is just about  
everything).

Consider, for example, that the 2009 budget for homeland security (the  
folks that protect us from terrorists) will likely be about $50  
billion. Don't get us wrong, we like the fact that people are trying  
to prevent terrorism, but even at its absolute worst, terrorists  
killed about 3,000 Americans in a single year. And less than 100  
Americans are killed by terrorists in most years. By contrast, the  
budget for the National Highway Traffic Safety Administration (the  
folks who protect us on the road) is about $1 billion, even though  
more than 40,000 people will die this year on the nation's roads. In  
terms of dollars spent per fatality, we fund terrorism prevention at  
about $17,000,000/fatality (i.e., $50 billion/3,000 fatalities) and  
accident prevention at about $25,000/fatality (i.e., $1 billion/40,000  
fatalities). This huge imbalance tells us that our priorities are  
seriously out of whack. (And don't even get us started on bigger  
killers like heart disease!)

The take-home message of all of this is that we should be a lot less  
afraid of many of the things that scare us. Yes, terrible things such  
as plane crashes, terrorism, and mass murder do happen. Likely each of  
these things will happen several more times before the year is  
finished. But the good news is that the chances that any of us will be  
affected by any of these events are so remote that we can safely relax  
and not worry about them. To the extent that we do try to prevent  
scary things from happening, we should put forth more effort to  
prevent real dangers like car accidents, heart attacks, and diabetes.  
Interestingly, many of the real dangers are things that we have a lot  
of control over (unlike mass murder). Therefore, to the extent that we  
try to prevent them, we might actually improve our quality of life.

(This post was co-authored by Ilan Shrira)