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Against picking up pennies

-1 [deleted] 13 December 2009 06:07AM

The eternally curious Tailsteak has written about how he always picks up pennies off the sidewalk. He's run a cost-benefit analysis and determined that it's better on average to pick up a penny than to pass it by. His mistake lies nowhere in the analysis itself; it's pretty much correct. His mistake is performing the analysis in the first place.

Pennies, you see, are easily the subject of scope insensitivity. When we come across a penny, we don't think, "Hey, that's something worth 0.05% of what I wish I had come across. I could buy a 25th of a gumball, a mouthful of an unhealthy carbonated beverage, a couple of seconds of footage on DVD, or enough gasoline to go a tenth of a mile." We think, "Hey, that's money," and we grab it.

The thing is, it's difficult to comprehend how little a penny is worth—we don't really have a separate concept for "mild happiness for a couple of seconds"—and we're likely to take risks that far outweigh the benefits. We don't think of bending over to pick up a penny as being a risky endeavour, but it's a penny. How much risk does it take to outweigh a penny? Surely the risk of "something unforeseen" easily does the job. Are you 99.999999% sure that picking up that penny won't kill you? You need a reason for every 9 (if you're ambivalent between using seven 9s and using nine 9s, you should use seven; the number of 9s is never arbitrary), and by the time you come up with eight reasons to pick up the penny, you'll have wasted several cents' worth of time. If you can reduce the probability of harm that far, I applaud you.

Of course, penny-grabbing doesn't have to involve actual pennies. Suppose that President Kodos of the Unified States of Somewhere (population 300 million) uses the word "idiot" in an important speech, causing the average citizen to scowl and ponder for one minute. Now, if a penny can buy you five seconds of happiness, and scowling and pondering brings the same amount of unhappiness, then that's twelve cents for every citizen, or 36 million dollars, of damage that Kodos just caused. Arguably, that's the value of a couple of human lives. As you can see, Kodos' decisions are extremely important. In this case, penny-grabbing would consist of anything less than trading precious seconds for precious human lives—if Kodos finds that he can save one life simply by going a few minutes out of his way, he should ignore it. (Photo ops and personal apologies are out of the question.) But keep in mind, of course, that avoiding saving someone's life because you have something better to do isn't rational unless you actually plan to do something better.

Comments (43)

Comment author: Alicorn 13 December 2009 02:50:19PM *  18 points [-]

I pick up pennies.

I rarely buy things in cash, and when I do, my retail experience tells me to avoid annoying the cashier and just hand over a bill rather than fiddling for quite a bit longer with exact change I might not even have. Since vending machines and parking meters won't take pennies, the way they eventually exit my purse is consistently this: somebody is holding a charity collection for something like mosquito nets or whatnot and I pull out a handful of change and they get all the pennies and nickels I have. It is not too unlikely that, through this mechanism, my picking up a penny has saved a life.

But this is all beside the point: time isn't fungible. None of the time I have spent picking up pennies had an available superior use all by its one-second-long lonesome. I find pennies to pick up when I'm walking somewhere and in little enough of a hurry to be taking in my surroundings; I find them when I have already decided to dedicate a morning to cleaning the house; I once found a twenty-pound-note on the ground in London while I was waiting for my aunt to rejoin me; I don't find them when I am hard at work accomplishing maximally valuable tasks, or even when I am in a state and location suitable to performing such work!

Comment author: Daniel_Burfoot 14 December 2009 06:51:30AM 1 point [-]

It is not too unlikely that, through this mechanism, my picking up a penny has saved a life.

I believe your calculation is off by at least an order of magnitude.

Comment author: wedrifid 14 December 2009 07:17:51AM 1 point [-]

I believe your calculation is off by at least an order of magnitude.

Just how unlikely is "too unlikely"? Maybe she just cares about lives an order of magnitude more than you expect her to.

Comment author: Alicorn 14 December 2009 02:22:43PM *  0 points [-]

Where did I perform anything best described as a "calculation"?

Comment author: wedrifid 13 December 2009 08:09:45AM *  11 points [-]

Are you 99.999999% sure that picking up that penny won't kill you? You need a reason for every 9 (if you're ambivalent between using seven 9s and using nine 9s, you should use seven; the number of 9s is never arbitrary), and by the time you come up with eight reasons to pick up the penny, you'll have wasted several cents' worth of time. If you can reduce the probability of harm that far, I applaud you.

What? No. I don't need to spend several cents worth of time thinking of reasons sufficient to get your permission to pick up a penny. I have absolutely no reason to even privilege the hypothesis that picking up a penny kill me. If I did, and if I felt the desire to think of reasons why not to be concerned about that I would probably start with reasons why the act of picking up a penny could extend my life. Perhaps the benefits of cerebellar stimulation or enhancing environmental awareness through penny grabbing biofeedback.

If I had a penny, I'd drop it. In fact, I drop 5c pieces as a matter of course (the smallest denomination of Australian currency, worth more than a penny but not accepted by most vending machines). That may technically count as littering but I haven't been fined yet. Even so, this particular argument against penny picking is bogus.

Comment author: Douglas_Knight 13 December 2009 11:36:21PM 5 points [-]

A couple of people have mentioned vending machines not taking pennies. We can roughly conclude from this that the owners of vending machines do not think pennies worth their while. They have much greater economies of scale than individuals for "rolling pennies," but they don't do it. Tailsteak mentions rolling pennies, but he fails to compute its cost.

In general, large organizations are a fertile source of assessments of practices. They'll think of costs that I won't, though they may not care about costs I do. For example, office buildings use fluorescent lighting and cities LED traffic signals not to save electricity, but to save the labor of replacement. Therefore, I try to think about maintenance labor and ignore the cost of electricity and the bulb. Thus, fluorescent bulbs are better for overhead lights than for desk lamps.

Comment author: wedrifid 13 December 2009 11:57:58PM 4 points [-]

A couple of people have mentioned vending machines not taking pennies. We can roughly conclude from this that the owners of vending machines do not think pennies worth their while. They have much greater economies of scale than individuals for "rolling pennies," but they don't do it. Tailsteak mentions rolling pennies, but he fails to compute its cost.

I had assumed the cost would have been related to the volume of the coin storage in the machine relative to the associated stock.

Comment author: Unknowns 14 December 2009 02:29:44AM 0 points [-]

Many banks will count them for you with a machine; you just hand them everything in a sack, so it doesn't have any significant cost.

Comment author: Bo102010 14 December 2009 03:06:23AM 2 points [-]

Going to the bank is not costless, especially since they keep hours that are not at all useful for wide swaths of the normal working population.

Comment author: Douglas_Knight 14 December 2009 02:18:21AM 0 points [-]

I had assumed the cost would have been related to the volume of the coin storage in the machine relative to the associated stock.

I probably should have said "hypothesize" rather than "conclude." My memory from when I operated an (antique) vending machine was that it had plenty of wasted space. I certainly wouldn't want to introduce a machine accepting pennies into the existing world in which they are otherwise useless. But if storage is an issue for the machine, it's also an issue for people. I don't normally carry any change.

Another source of information is automated coin counters. I had one bank that offered the service for free to customers and another that charged a percentage. I've seen a free-standing one (a vending machine that takes pennies!) that charges 15%. So maybe Tailsteak should discount the number by 15%, but no more.

Comment author: Cyan 14 December 2009 03:32:22PM 4 points [-]

This comment thread is a penny I will not pick up.

Comment author: wedrifid 14 December 2009 03:39:23PM 2 points [-]

Your m.... nevermind.

Comment author: Cyan 14 December 2009 08:46:17PM 1 point [-]

Were you about to make a "your mom" joke?

Comment author: CronoDAS 13 December 2009 10:20:27PM 9 points [-]

We don't think of bending over to pick up a penny as being a risky endeavour, but it's a penny. How much risk does it take to outweigh a penny? Surely the risk of "something unforeseen" easily does the job. Are you 99.999999% sure that picking up that penny won't kill you? You need a reason for every 9 (if you're ambivalent between using seven 9s and using nine 9s, you should use seven; the number of 9s is never arbitrary), and by the time you come up with eight reasons to pick up the penny, you'll have wasted several cents' worth of time. If you can reduce the probability of harm that far, I applaud you.

This is bullshit. It doesn't matter what the absolute risk of picking up the penny is; what matters is whether not picking up the penny is less risky than picking up the penny. And, in general, there is no particular reason to believe that there is any difference in risk between picking it up and not picking it up.

Comment author: Daniel_Burfoot 14 December 2009 06:46:30AM -1 points [-]

This is bullshit. It doesn't matter what the absolute risk of picking up the penny is; what matters is whether not picking up the penny is less risky than picking up the penny. And, in general, there is no particular reason to believe that there is any difference in risk between picking it up and not picking it up.

This is a deep and subtle fallacy. A course of action (or plan) that involves picking up a penny is more complicated than one that does not. Complex plans must be penalized in the same way that complex theories must be (a plan is really just a theory that a certain course of action will lead to a good outcome).

One of my strong personal beliefs is that people drastically underestimate how much complexity hurts.

Comment author: [deleted] 15 December 2009 03:31:25AM 2 points [-]

Complex plans must be penalized in the same way that complex theories must be (a plan is really just a theory that a certain course of action will lead to a good outcome).

Mm, no. Theories are mutually exclusive. The thing that makes a complex theory unlikely is the fact that it has 10^N, for large N, other theories to compete with. By your definition of a plan, plans are not mutually exclusive, so this analogy vanishes. Of course, you could define a plan as the theory that a certain course of action will lead to the best outcome out of all possible plans, in which case your statement would be true, but wouldn't apply: the agent that finds the best possible plan before acting starves to death, decays, and is forgotten long before ever eating the food in front of it.

Comment author: Daniel_Burfoot 15 December 2009 02:02:39PM 0 points [-]

I find this comment confusing. Represent a plan as a list of discrete actions. Then "X,Y" is different from "X,Y,Z" where X/Y/Z are actions. Picking "X,Y,Z" means you did not pick "X,Y". The number of plans is also exponential in the number of actions, so a more complex (longer) plan has an exponentially greater number of competitors.

Comment author: [deleted] 16 December 2009 05:58:08PM 0 points [-]

You defined a plan as a theory that a certain course of action will lead to a good outcome. Picking "X,Y,Z" does not mean you don't think "X,Y" will also lead to a good outcome. Therefore, they aren't really competitors.

Comment author: wedrifid 14 December 2009 07:36:51AM *  1 point [-]

This is a deep and subtle fallacy.

That isn't a fallacy. You just claim (right or wrong) to have more evidence about the risks in question.

A course of action (or plan) that involves picking up a penny is more complicated than one that does not.

Perhaps. But what if the two plans in question are as follows?

  1. Keep on walking without picking up the penny.

That's right. 2 isn't a plan. You go about walking down the street. Hundreds of muscles move with the calibration necessary to maintain both balance and forward momentum under the influence of gravity. You respond to stimulus from the inner ear to correct imbalance. You instinctively compensate for unexpected instabilities in your footing. If you see a cricket ball (base ball if any Americans are confused) flying out at you from a nearby backyard you duck or catch it. You pick up money.

Now, I'm not saying the above is how I react. I see 5c and 10c coins and have a mild aversive reaction that balances the money grab impulse. But I am not comfortable in asserting that my reactions are particularly safer because they use less actual action. The components of plans that hurt me are the initiative and executive requirements. "Just take the money" may be the better option in such a situation and my inhibition just a premature optimisation.

Comment author: Daniel_Burfoot 14 December 2009 01:47:04PM 0 points [-]

I'm not really sure what you mean. Of course it is hard to assign complexities to things like plans. Even more difficult is the problem of weighing increased complexity against increased performance. But it's strange to object to the statement that of the two plans {X, X+pick up penny}, the latter is more complicated.

Comment author: wedrifid 14 December 2009 03:02:59PM *  1 point [-]

But it's strange to object to the statement that of the two plans {X, X+pick up penny}, the latter is more complicated.

I suggest that for people with a habit of picking up currency that they come across the plans, as implemented by their brains would be better described as {Y, Y + suppress pick-up-valued-item impulse in the case of pennies}. This sort of change is (a trivial instance of) the complexity that most matters to humans. Until the habit is entrenched the stimulus of a penny will have a transient but measurable deleterious effect on concentration. The risk of, for example, stumbling is also increased, with a well practised visual stimulus to motor action coupling interrupted by executive override.

I argue that the optimisation of literal penny grabbing protocols is an instance of metaphorical penny grabbing that does, in fact, waste more than it saves, as measured by complexity

Comment author: Daniel_Burfoot 15 December 2009 02:17:00PM 0 points [-]

I suggest that for people with a habit of picking up currency that they come across the plans, as implemented by their brains would be better described as {Y, Y + suppress pick-up-valued-item impulse in the case of pennies}.

I buy this point, but it seems like we're talking about different issues.

Penny grabbing is probably not a good example of the problem I am really concerned with. This is the situation where there is some action X that we have to decide whether or not to do, and we have relatively little information to bring to bear. A good example came up in the financial crisis: "should we bail out the banks?" Well, some people think we should, others disagree. There are all these hard-to-evaluate pros and cons in the outcome-prediction process, but at the end of the day the pros seem to add up to a bit more than the cons.

The problem is that some people see the question as symmetric: either we bail out the banks or we don't. No reason to prefer a priori one course of action over the other. But my whole point is that we should prefer the simpler action a priori, and require much more concrete evidence in favor of the complex plan before we choose it.

Comment author: wedrifid 15 December 2009 02:38:50PM 0 points [-]

There are all these hard-to-evaluate pros and cons in the outcome-prediction process, but at the end of the day the pros seem to add up to a bit more than the cons.

An interesting topic and I disagree.

The problem is that some people see the question as symmetric: either we bail out the banks or we don't. No reason to prefer a priori one course of action over the other. But my whole point is that we should prefer the simpler action a priori, and require much more concrete evidence in favor of the complex plan before we choose it.

I read your example and thought {X, X + bail out banks}. But since you are a bailout advocate I suppose you wouldn't have brought up the example if you thought the complexity weighed in against your position. So I infer that you mean {bail out banks, do a more complex thing Y}. For many instances of Y that people are likely to propose I expect I would agree with your judgement, with the complexity being a significant factor.

Comment author: Daniel_Burfoot 15 December 2009 03:53:26PM 0 points [-]

But since you are a bailout advocate I suppose you wouldn't have brought up the example if you thought the complexity weighed in against your position. So I infer that you mean {bail out banks, do a more complex thing Y}.

No, I'm against the bailout! My point is that the bailout is complex, therefore it should be penalized even if it seems to have a good predicted outcome. I see the choice as {X=no intervention, Y=bail out banks}; the former is far simpler, so it should be preferred.

Comment author: wedrifid 15 December 2009 03:57:55PM 0 points [-]

No, I'm against the bailout! My point is that the bailout is complex, therefore it should be penalized even if it seems to have a good predicted outcome. I see the choice as {X=no intervention, Y=bail out banks}; the former is far simpler, so it should be preferred.

Ahh, ok. I read the "the pros seem to add up to a bit more than the cons" part and assumed the reverse.

Comment author: [deleted] 14 December 2009 02:12:11PM 1 point [-]

And, in general, there is no particular reason to believe that there is any difference in >risk between picking it up and not picking it up.

I think there is a small difference. What if the person who dropped the penny had H1N1? If one or multiple people handled the penny recently picking it up might be as risky as shaking their hands. That's certainly not a big risk, but its a non-zero risk that you can avoid by not picking up the penny.

Comment author: Psychohistorian 13 December 2009 08:25:32PM *  2 points [-]

The author apparently derives a kick of arational satisfaction from picking up pennies, perhaps as a means of reinforcing a poorly-reasoned conclusion. If he values finding them for its own sake, and not for the sake of the material goods he can buy, picking them up would make sense. Actively searching them out would be rational. Buying a metal detector and walking around with it could conceivably be rational, if he got a really big kick out of finding them. "It's money!" is not rational if your sole goal is enriching yourself, but if it provides that arational kick, that's a reason to keep your eyes on the ground.

Comment author: [deleted] 15 December 2009 03:32:49AM 0 points [-]

"The author" is a rather ambiguous phrase. Why don't you call him Tailsteak?

Comment author: Psychohistorian 16 December 2009 03:17:50AM 0 points [-]

Practically, because I just didn't notice, and the statement seemed unambiguous. Since it was a highest-level comment and a direct response to the post, "the author" was not a reference to person I was replying to. If I meant to talk about you, I would have just said, "you."

Subconsciously, the fact that I have no idea who he is, don't particularly care for that name, and feel that naming him would give him status that I don't believe he's earned all factored into my decision, though none at any conscious level.

Comment author: timtyler 13 December 2009 01:31:47PM 1 point [-]

Picking up pennies might make sense - if you do not have a well-paid job.

However, the real problem is looking for pennies. That is time-consuming, has poor rewards, and unless you do it, you don't find very many pennies.

Comment author: kpreid 13 December 2009 02:10:09PM 3 points [-]

Is anyone proposing looking for pennies? I thought the question was of picking up pennies which one notices.

Comment author: Douglas_Knight 13 December 2009 04:30:31PM 2 points [-]

Is anyone proposing looking for pennies? I thought the question was of picking up pennies which one notices.

If you pick up the pennies you notice, you will start noticing more. You will commit brain resources to the task of looking. I don't know if this comes at the expense of other uses you could have made.

Comment author: timtyler 13 December 2009 02:13:24PM 1 point [-]

The article author says he sometimes averages a penny a day. I figure he is probably walking along with his head down a fair bit of the time.

Comment author: wedrifid 13 December 2009 01:44:39PM 0 points [-]

However, the real problem is looking for pennies. That is time-consuming, has poor rewards, and unless you do it, you don't find very many pennies.

Not to mention the expense of the plane ticket!

Comment author: PhilGoetz 16 December 2009 01:39:34AM 1 point [-]

I don't pick up pennies. It's too risky to the lower back.

Comment author: PlaidX 14 December 2009 05:36:18AM 1 point [-]

I don't pick up anything less than a quarter, and in fact if i find dimes or nickels in my pocket i just throw them away... i do all my banking electronically, and the cost of going somewhere that i could exchange small change for usable money, plus the cost of storing and rummaging through the nickels looking for quarters, far outweighs the $2.44 per five years or whatever it is i'd make.

Quarters are valuable because you can use them in machines, and particularly for doing laundry, they're the ONLY thing you can use in machines... there's no change machine here...

Comment author: nerzhin 14 December 2009 08:34:00PM 2 points [-]

It's not clear to me that throwing away change is less of a hassle than throwing it in your coin jar at home. You have to do something with it either way.

Eventually the coin jar gets full enough that it's worth taking to the bank - last time I did this I had about $60 from five years, much more than your $2.44 estimate, though, clearly, still not significant.

Comment author: MrHen 17 December 2009 06:41:10PM 2 points [-]

I do the same thing, but I also buy more stuff with cash. If you do all of your purchasing with a credit card you will have a shockingly low amount of change.

Comment author: PlaidX 20 December 2009 03:30:14AM *  1 point [-]

Yeah, I always use a credit card. The difference between throwing change away and putting it in a jar is that one is a mindless reaction to going through my pockets and somehow coming up with a nickel, and the other is something I would actually have to remember to do once I got home.

Also, when I say I "throw it away", I mean that in most cases, I just literally toss it on the ground. Society doesn't consider it litter, so what the hey...

Comment author: Bo102010 14 December 2009 03:10:13AM 1 point [-]

I used to not pick up pennies, because I hated carrying and storing change (except for quarters, which I needed for laundry)

Now that I live with my fiancee, I always do, though, because she's kept a large piggy bank since childhood, and I get a tiny little kick out of coming home and saying "I brought home a present... for the pig!" or something.

Comment author: Dustin 13 December 2009 10:51:31PM 1 point [-]

Pennies, you see, are easily the subject of scope insensitivity. When we come across a penny, we don't think, "Hey, that's something worth 0.05% of what I wish I had come across. I could buy a 25th of a gumball, a mouthful of an unhealthy carbonated beverage, a couple of seconds of footage on DVD, or enough gasoline to go a tenth of a mile." We think, "Hey, that's money," and we grab it.

Wrong for me. When I see a penny, I think "I can't buy anything without a lot of those" and don't pick it up.

Actually, I don't even do that. I probably did at one point but then built up a heuristic where I don't even think that....I just don't pick up pennies.

Comment author: Unknowns 13 December 2009 08:11:21AM 1 point [-]

Your analysis takes into account secondary effects of Kodos's decisions, and this is why "penny grabbing" would consist of anything less than trading seconds for lives. But penny grabbing also has secondary effects: and why assume these secondary effects will be bad instead of good? The secondary effects might well be good, and if so, they can multiply just like the consequences of his other decisions.

Comment author: Pfft 15 December 2009 12:09:41AM *  0 points [-]

Are you 99.999999% sure that picking up that penny won't kill you?

This argument does not seem to be a valid reply to the post you link to. Picking up pennies does not seem very risky -- in particular it seems no more risky than many other jobs we would be willing to perform for $36/h. This is the beauty of quantifying it in terms of hourly wage -- we won't have to perform insanely complicated calculations about the risk and reward, we can just compare the risk and the reward to other routine things we do for a living.

That said, I'm a bit doubtful about his assertion that picking it up takes less than a second. 5 seconds seems like an equally reasonable estimate to me, and that would put the problem in a quite different light.

And on a personal note I throw a huge pile of pennies in the trash every other year, so having one more carries a negative utility for me. :)