Psychology Today on Risk Assessment

Yet another article on the topic. An excerpt:

We substitute one risk for another.

Insurers in the United Kingdom used to offer discounts to drivers who purchased cars with safer brakes. “They don’t anymore,” says John Adams, a risk analyst and emeritus professor of geography at University College. “There weren’t fewer accidents, just different accidents.”

Why? For the same reason that the vehicles most likely to go out of control in snowy conditions are those with four-wheel drive. Buoyed by a false sense of safety that comes with the increased control, drivers of four-wheel-drive vehicles take more risks. “These vehicles are bigger and heavier, which should keep them on the road,” says Ropeik. “But police report that these drivers go faster, even when roads are slippery.”

Both are cases of risk compensation: People have a preferred level of risk, and they modulate their behavior to keep risk at that constant level. Features designed to increase safety—four-wheel drive, Seat belts, or air bags—wind up making people drive faster. The safety features may reduce risks associated with weather, but they don’t cut overall risk. “If I drink a diet soda with dinner,” quips Slovic, “I have ice cream for dessert.”

Posted on January 31, 2008 at 11:45 AM10 Comments


Wiredforlife January 31, 2008 6:29 PM

I have a question in regards to risk assessments and Wireless IDS.

How does one communicate that Wireless IDS systems do not increase security because (in my case) they increase false positive noise, and is security is better provided through other means? Anybody seen any documents out there saying something like that?


Joe Patterson January 31, 2008 7:59 PM

The one of these that bugs me is #8, which starts:

“If the risks of smoking marijuana are coldly compared to those of playing high-school football, parents should be less concerned about pot smoking.”

That may be true, if the only risk you care about is death. I don’t know any parent that’s afraid their child might overdose on marijuana. I do know some who are afraid that if their kids smoke pot, they’ll become lazy stupid slobs. This may be a valid risk. From my own personal observation, I have determined that I am aware of pot smoking among a higher percentage (no pun intended) of lazy stupid slobs than among the rest of the population that I’ve met. To me, there are three likely reasons for this:

1) smoking pot turns you into a lazy stupid slob. I know of at least one firm counterexample, so it’s certainly not universal among pot-smokers, but this theory is probably the most common thing that people think.

2) lazy stupid slobs like pot more than the rest of us do. While entirely possible, parents don’t like thinking this because it means they have no control. If smoking pot causes stupidity, then maybe they can keep their kids smart by keeping them away from pot. If stupidity causes pot smoking, then their kid is either stupid or not, and there’s nothing they can do about it.

3) lazy stupid slobs don’t care as much whether or not I know that they smoke pot. This is probably true whether or not 1 or 2 is also. And it’s a difficult sampling bias to avoid.

Bryan McGinty February 1, 2008 12:02 AM


What about comparing pot smokers to people consuming alcohol. Alcohol makes people aggressive and take risks. I don’t believe the same can be said for smoking pot. My guess is that alcohol would turn more people into aggressive, stupid slobs than pot would turn people into lazy, stupid slobs.

The problem is that alcohol is a legal drug, but it has a very high impact on the community.

unary February 1, 2008 6:29 AM


you left off the option that many, many respectable, productive and intelligent people smoke pot, and due to the negative perception of pot smokers, they just prefer not to make a small indulgence a public display.

personally, i find the coked-to-the-eyeballs currency trader more scary than the even the cliche’ pot-smoking revolutionary hippy, lazy or not….

aikimark February 1, 2008 8:03 AM

aaaahhh…the 80s.
* Junk Bonds
* Cocaine
* Failed Savings & Loans debacle
* Trickle-down (voodoo) economics
* Deregulation

Carried over from their late 70s start:

moondog February 2, 2008 10:09 AM

the part about risks associated with driving in a car which appears safer is totally in line with my own personal risk factor. i will cut and weave in traffic in my car, speed well above posted limits when possible on the freeway and take turns hard enough to make the tires squeal a bit.

but when i ride my motorcycle i rarely go above the posted limit, i only weave in traffic because it’s stuck and i’m allowed to, and i don’t drive faster than 35-40mph when i go between the cars in that situation. all because i know i am at a much much higher risk of instant death on the back of that bike than i am with “four on the floor”.

of course, if it’s snowing out i’d rather have rear wheel drive than four wheel or front wheel because it’s easier to do donuts in the snow with rear wheel drive 😉

Joe Patterson February 3, 2008 2:14 PM


That’s just another way of looking at #3. I said it in terms of the stupid not caring whether I knew they smoked pot or not, but it would be just as valid to say it as the smart caring whether people know they smoke pot. A more thorough statement would be that lazy stupid slobs who smoke pot are less concerned about whether other people know that they smoke pot than respectable productive intelligent people who smoke pot are. It’s just a matter of relative concern.

Just to be clear, the stereotype of lazy stupid slob pot smokers is one I tentatively accepted without much thought until such time as I met a strong counter-example (an energetic, motivated, and generally brilliant biochemist who smoked a lot of pot, but was completely unlike any pothead stereotype). At that point, I did put some thought into the stereotype and realized the strong potential for sampling bias and mistaken assumptions of the directionality of the causal relationship implied by any correlation that might be found.

As a parent today, I am more concerned about my kids smoking pot than playing football, but it has nothing to do with a risk of death. It doesn’t even really have much to do with a fear that it will stunt my children’s brains. The real risk I’m hoping for them to avoid is jail, which is probably the worst side effect of almost any means to achieve momentary chemical euphoria.

perianwyr February 4, 2008 5:59 PM


Well, if the last illegal-now-legal drug we had is any indication, just about everyone. Is your analysis an effective judgment about the social profile of dope smokers? It really can’t be in the sense you imagine them, if only because burnouts have vastly less to lose should their habits be revealed. You also appear to be trying to equate casual dope smoking with heavy dope smoking. This locks you out of proper social profiling as well.

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