I'm not sure I buy that this is completely about scope insensitivity rather than marginal utility and people thinking in terms of their fair share of a kantian solution. Or put differently, I think the scope insensitivity is partly inherent in the question, rather than a bias of the people answering.

Let's say I'd be willing to spend $100 to save 10 swans from gruesome deaths. How much should I, personally, be willing to spend to save 100 swans from the same fate? $1000? $10,000 for 1,000 swans? What about 100,000 swans -- $1,000,000?

But I don't have $1,000,000, so I can't agree to spend that much, even if I believe that it is somehow intrinsically worth that much. When I'm looking at what I personally spend, I'm comparing my ideas about the value of saving swans to the personal utility I give up by spending that money. $100 is a night out. $1000 is a piece of furniture or a small vacation. $10,000 is a car or a year's rent. $100,000 is a big chunk of my net worth and a sizable percentage of what I consider FU money. As I go up the scale my pain increases non-linearly, and my personal pain is what I'm measuring here.

So considering a massive problem like saving 2 million swans, I might take the Kantian approach. If say, 10% of people were willing to put $50 toward it, that seems like it would be enough money, so I'll put $50 toward it figuring that I'd rather live in a world where people are willing to do that than not.

Like many interpretations of studies like this, I think you're pulling to trigger on an irrationality explanation too fast. I believe that what people are thinking here is much more complicated than you're giving them credit for and with an appropriate model their responses might not appear to be innumerate.

It's a hard question to ask in a way that scales appropriately, because money only has value based on scarcity, so you can't say "If you are emperor of a region with unlimited money to spend, what it is worth to save N swans?" because the answer is just "as much as it takes". Money only has value if it is scarce, and what you're really interested in is "Using 2007 US dollars as units: How much other consumption should be foregone to save N swans?". But people can only judge that accurately from their own limited perspective where they have only so much consumption capacity to go around.

The same idea goes for insisting that the charity you donate to is actually good at its mission. If you get your warm glow from the image of yourself as a good person, and if your dollars follow your glow, then competition among charitable organizations will take the form of trying to get good at triggering that self-image. If you get your glow from results, and if your dollars follow that, then charities will have much better incentives.

Once upon a time, three groups of subjects were asked how much they would pay to save 2000 / 20000 / 200000 migrating birds from drowning in uncovered oil ponds. The groups respectively answered $80, $78, and $88 [1]. This is scope insensitivity or scope neglect: the number of birds saved - the scope of the altruistic action - had little effect on willingness to pay.

An alternate interpretation is that people conceptualize the problem not in terms of absolute number of birds saved, but in terms of the fraction of birds saved. And they have no idea how many migrating birds there are. Presenting the number 2000, or 200,000, probably suggests to them that that's on the order of how many migrating birds there are.

A proposed health program to save the lives of Rwandan refugees garnered far higher support when it promised to save 4,500 lives in a camp of 11,000 refugees, rather than 4,500 in a camp of 250,000. A potential disease cure had to promise to save far more lives in order to be judged worthy of funding, if the disease was originally stated to have killed 290,000 rather than 160,000 or 15,000 people per year.

Hmm... pinging my head for a plausible reason for why I would rate one health program higher or lower this math popped out: Program A promised to save 4,500 / 11,000 refugees; Program B promised to save 4,500 / 250,000 refugees. Program A has a significantly higher "success rate." Since I know nothing about how health programs work the potentially naive request that Program A is chosen and sent to work at Site B. Why wouldn't its success rate work with larger numbers? I assume that reality has a few gotchas but I can see the mental reasoning there.

Likewise, for the disease cures, it would make more sense to work on a cure that had a much higher success rate. A cure that works 90% is "better" than a cure that works 10% of the time. The math in terms of lives saved will frustrate the dying and those who care about them but the value placed on the cure may not be counting lives saved. In these examples, the scope problem may be pointing toward the researchers and the participants valuing different things instead of the participants values breaking down around large numbers.

I am interested in comparing Program A (4,500 / 11,000 refugees saved) to a Program C (100,000 / 250,000). The ratios are much closer (41% saved and 40%, respectively). Also, merely asking the question, "Which cure is more valuable?" and listing the cures with different stats. Would this be enough to learn of any correlations between the amount of support and the perceived value/success of the options?

Another experiment could explicitly instruct people to assign money to Programs A, B, and C with the goal of saving the most people. Presumably this will help the participants switch whatever values they have with the values of saving lives. Would the results be different? Why or why not?

This certainly does not apply to the oiled birds or protecting wilderness. Also of note, I did not read any of the linked articles. Perhaps my questions are answered there?

I perceive that I've neglected to convey the existence of a gigantic body of supporting evidence.

Michael Sullivan, see e.g. http://www.sas.upenn.edu/~baron/cv1.htm:

Embedding. Kahneman and Knetsch (1992) asked some subjects their WTP for improved disaster preparedness and other subjects their WTP for improved rescue equipment and personnel. The improved equipment and personnel were thus embedded in'' the improved disaster preparedness, so the preparedness included the equipment and personnel, and other things too. WTP was, however, about the same for the larger good and for the smaller good included in it. Kahneman and Knetsch called this theperfect embedding effect,'' presumably because a demonstration of it requires perfect equality of WTP of the two goods. When subjects were asked their WTP for the smaller good after they had just been asked about the larger one, they gave much smaller values for the smaller good than for the larger one, and much smaller values than those given by subjects who were asked just about the smaller good. This order effect is called the regular embedding effect.'' It demonstrates that a good seen as embedded in a larger good has reduced value. Kemp & Maxwell (1993) replicated this regular embedding effect, starting with a broad spectrum of public goods, and narrowing the good down in several steps, obtaining WTPs for an embedded good that were 1/300 of WTP for the same good in isolation. Adding up. In a related demonstration, Diamond et al. (1993), asked subjects their WTP values for preventing timber harvesting in federally protected wilderness areas. WTP for the prohibition in three areas was not much (if any) higher than WTP for prohibition in one of the areas alone. This result cannot be explained by assuming that subjects thought that protection of one area was sufficient: when they were asked their WTP to protect one area assuming that another was already protected, or a third area assuming that two were protected, their WTP values were just as high as those for protecting the first area. More generally, in this kind ofadding-up effect,'' respondents are asked their WTP for good A (e.g., a single wilderness area), for good B assuming that good A has been provided already, and for goods A and B together. WTP for A and B together is much lower than the sum of the WTP for A and for B (with A provided). Schulze, McClelland, & Lazo (1994) found similar results in a within-subject design: each subject rated A, B, and A and B together.

Those yellow LiveStrong bracelets are a great example. They're about $1 or so, and purchasers wear them around all day advertising that they care about cancer. How many of those people would have donated an equivalent amount (just a buck) without the badge of caring they get to wear around?

Actually, in my experience it's the other way round - people feel they're doing their bit just by wearing the bracelets, so they'll pay less for a bracelet than they'd donate anonymously.

But like most anecdotes, that one story doesn't tell you anything - we need statistics if we want to truly know how people behave.

I strongly favor the "warm glow" explanation, but I'd take it a step further.

For most people, the warm glow is only worth it if they get social credit.

Those yellow LiveStrong bracelets are a great example. They're about $1 or so, and purchasers wear them around all day advertising that they care about cancer. How many of those people would have donated an equivalent amount (just a buck) without the badge of caring they get to wear around?

How do people react if told "Here is a fixed amount of cash, that must go to charity. How do you wish it to be spent?"

Might that not distinguish "purchase of moral satisfaction" from "scope neglect"?

Your conclusion matches your data, but the data is suspiciously focused on charity. Is scope neglect easier to elicit in such contexts? Other explanations include it being hard to make large numbers relevant, and lack of imagination by researchers.

Do we value saving lives independently of the good feelings we get from it?

Sure: there's the issues of rewards, reputation and status to consider. The effect of saving lives on the former may scale somewhat linearly - but the effect on the others certainly does not.

From Abhijit V. Benerjee and Esther Duflo's Poor Economics,

Researchers gave students $5 to fill out a short survey. They then showed them a flyer and asked them to make a donation to Save the Children, one of the world’s leading charities. There were two different flyers. Some (randomly selected) students were shown this:Food shortages in Malawi are affecting more than 3 million children; In Zambia, severe rainfall deficits have resulted in a 42% drop in maize production from 2000. As a result, an estimated 3 million Zambians face hunger; Four million Angolans—one third of the population—have been forced to flee their homes; More than 11 million people in Ethiopia need immediate food assistance.

Other students were shown a flyer featuring a picture of a young girl and these words:Rokia, a 7-year-old girl from Mali, Africa, is desperately poor and faces a threat of severe hunger or even starvation. Her life will be changed for the better as a result of your financial gift. With your support, and the support of other caring sponsors, Save the Children will work with Rokia’s family and other members of the community to help feed her, provide her with education, as well as basic medical care and hygiene education. The first flyer raised an average of $1.16 from each student. The second flyer, in which the plight of millions became the plight of one, raised $2.83. The students, it seems, were willing to take some responsibility for helping Rokia, but when faced with the scale of the global problem, they felt discouraged.

Some other students, also chosen at random, were shown the same two flyers after being told that people are more likely to donate money to an identifiable victim than when presented with general information. Those shown the first flyer, for Zambia, Angola, and Mali, gave more or less what that flyer had raised without the warning—$1.26. Those shown the second flyer, for Rokia, after this warning gave only $1.36, less than half of what their colleagues had committed without it. Encouraging students to think again prompted them to be less generous to Rokia, but not more generous to everyone else in Mali.

This may be nitpicky but I found an errata in the references. [3] I believe should be 1993 instead of 1995.

That said, there are 3 broken links for me - [4], [6] and [7] - and the non-broken links don't seem to currently be providing full text access. So, here's an updated references table, with links to full text access in each except for the book in [3] which has an amazon link instead:

[1] Desvousges, W. Johnson, R. Dunford, R. Boyle, K. J. Hudson, S. and Wilson K. N. (1992). Measuring non-use damages using contingent valuation: experimental evaluation accuracy. Research Triangle Institute Monograph 92-1.

[2] Kahneman, D. 1986. Comments on the contingent valuation method. Pp. 185-194 in Valuing environmental goods: a state of the arts assessment of the contingent valuation method, eds. R. G. Cummings, D. S. Brookshire and W. D. Schulze. Totowa, NJ: Roweman and Allanheld.

[3] McFadden, D. and Leonard, G. 1993. Issues in the contingent valuation of environmental goods: methodologies for data collection and analysis. In Contingent valuation: a critical assessment, ed. J. A. Hausman. Amsterdam: North Holland.

[4] Kahneman, D., Ritov, I. and Schkade, D. A. 1999. Economic Preferences or Attitude Expressions?: An Analysis of Dollar Responses to Public Issues, Journal of Risk and Uncertainty, 19: 203-235.

[5] Carson, R. T. and Mitchell, R. C. 1995. Sequencing and Nesting in Contingent Valuation Surveys. Journal of Environmental Economics and Management, 28(2): 155-73.

[6] Baron, J. and Greene, J. 1996. Determinants of insensitivity to quantity in valuation of public goods: contribution, warm glow, budget constraints, availability, and prominence. Journal of Experimental Psychology: Applied, 2: 107-125.

[7] Fetherstonhaugh, D., Slovic, P., Johnson, S. and Friedrich, J. 1997. Insensitivity to the value of human life: A study of psychophysical numbing. Journal of Risk and Uncertainty, 14: 238-300.

I came across an interesting book that includes the topic of scope insensitivity: "Determining the value of non-marketed goods: economics, psychological, and policy relevant aspects of contingent valuation methods" by Raymond J. Kopp, Werner W. Pommerehne, Norbert Schwarz. They suggest that while scope insensitivity on surveys is possible, it is not inevitable.

After providing an impressive list of studies rejecting the insensitivity hypothesis, they highlight two in particular: "First, the scope insensitivity hypothesis is strongly rejected (p<.001) by two large recent in-person contingent valuation studies, Carson, Wilks and Imber (1994) and Carson et al. (1994), which used extensive visual aids and very clean experimental designs to value goods thought to have substantial passive use considerations."

In order to prevent scope insensitivity, they suggest that the "respondent must (i) clearly understand the characteristics of the good they are asked to value, (ii) find the CV scenario elements related to the good's provision plausible, and (iii) answer the CV questions in a deliberate and meaningful manner."

Douglas, I understand that scope insensitivity decreases substantially, but does not go away entirely, when personal profits are at stake.

It's not easy to devise experiments that distinguish unambiguously between the explanations that center around prototype-dominated affect, versus the warm glow of moral satisfaction. It seems pretty likely that both effects are at work.

Who are you to say for Z person that the value of saving X number of Y valuable commodity is linear?

This may be nitpicky but I found an errata in the references. [3] I believe should be 1993 instead of 1995.

That said, there are 3 broken links for me - [4], [6] and [7] - and the non-broken links don't seem to currently be providing full text access. So, here's an updated references table, with links to full text access in each except for the book in [3] which has an amazon link instead:

[1] Desvousges, W. Johnson, R. Dunford, R. Boyle, K. J. Hudson, S. and Wilson K. N. (1992). Measuring non-use damages using contingent valuation: experimental evaluation accuracy. Research Triangle Institute Monograph 92-1.

[2] Kahneman, D. 1986. Comments on the contingent valuation method. Pp. 185-194 in Valuing environmental goods: a state of the arts assessment of the contingent valuation method, eds. R. G. Cummings, D. S. Brookshire and W. D. Schulze. Totowa, NJ: Roweman and Allanheld.

[3] McFadden, D. and Leonard, G. 1993. Issues in the contingent valuation of environmental goods: methodologies for data collection and analysis. In Contingent valuation: a critical assessment, ed. J. A. Hausman. Amsterdam: North Holland.

[4] Kahneman, D., Ritov, I. and Schkade, D. A. 1999. Economic Preferences or Attitude Expressions?: An Analysis of Dollar Responses to Public Issues, Journal of Risk and Uncertainty, 19: 203-235.

[5] Carson, R. T. and Mitchell, R. C. 1995. Sequencing and Nesting in Contingent Valuation Surveys. Journal of Environmental Economics and Management, 28(2): 155-73.

[6] Baron, J. and Greene, J. 1996. Determinants of insensitivity to quantity in valuation of public goods: contribution, warm glow, budget constraints, availability, and prominence. Journal of Experimental Psychology: Applied, 2: 107-125.

[7] Fetherstonhaugh, D., Slovic, P., Johnson, S. and Friedrich, J. 1997. Insensitivity to the value of human life: A study of psychophysical numbing. Journal of Risk and Uncertainty, 14: 238-300.

If three groups of subjects were asked how much they would pay to save 2000/20000/200000 birds... Was one group asked how much they would pay to save 2000 birds, another group asked how much they would pay to save 20000 birds, and the final group asked how much they would pay to save 200000 birds? Or was one group asked how much they would pay to save 2000, then 20000, then 200000 birds, and the experiment repeated on the other two groups? I didn't quite understand... I think I was reading too hard into the subtext. But I'm leaning towards the first one, can anyone elaborate?

Keyword connection for literature searches: Loss Aversion

Jonah Lehrer has blogged recently about what he described as loss aversion -- doctors will take more risks if the same problem is framed as reducing loss of life rather than saving lives.

He summarizes some of the same papers mentioned in the post and also a new Feb 2010 PNAS paper, "Amygdala damage eliminates monetary loss aversion".

The ideas overlap with those in Circular Altruism, I'm not sure which post I originally meant to make this comment under.

The world of business tends to emphasize pattern over particular. But intellectual aspects of pattern prevents people from caring.

So the marketer would win by using the sad and more concrete image of the oily bird, persuading more people by means of the Ludic fallacy.

how many lives an action saves is less important than the emotional connotations of the act which takes the lives. take micronutrient dispersal programs vs terrorism. malnutrition kills orders of magnitude more people and yet far more money is spent on terrorist prevention (well, mostly terrorist prevention signaling, but that's another topic). This is because fighting terrorism is more exciting than fighting scurvy. The order of magnitude difference in impact is ignored when evaluating which thing to spend money on. This makes choosing terrorism easier as saving 100 people from terrorism is much better for public relations than saving 100 random kids with goiters.

A proposed health program to save the lives of Rwandan refugees garnered far higher support when it promised to save 4,500 lives in a camp of 11,000 refugees, rather than 4,500 in a camp of 250,000.

The 4,500 out of 11,000 ratio might cause the people to examine the claims of the charity that "intends to save" the 4,500 less closely than they would examine any claim at effecting a small minority ratio in a larger group, for several possibly valid reasons. When managing large numbers of people is involved in the task, "saving" the 4,500 might not seem as manageable. This might partially come down to a question of skepticism against the claims of the charity.

Maybe when the 4,500/11,000 lives are "being saved" the people imagine the aid will actually get to them, or will get to the group as a whole. Whereas, when the 4,500/250,000 number is used, the people imagine that the sociopaths of the 250,000 group will find a way to intercept the aid, the amount won't be enough, etc.

In the prior cases, it isn't that the people empathize with the sufferers less, it's that differences in scope start to force them to imagine what might go wrong with the best intentions of the charity, and consequently, bring to light the marginal utility question others have raised. (Such as "I could spend this money on a charity I previously have a commitment to, and a relationship with, rather than throw it at a distant African problem that may or may not be able to optimally use my gift." ...If I'm going to spend it on a charity at all.)

Moreover, it would be interesting to see if their experiments were designed in a rational manner that excluded most of Hansen's list of cognitive biases. Ie: the human version of Feynman's rat-in-a-maze experimental design problem in mind: "with the maze the rat must walk through being buried in sand, so it can't hear the echoes of its footfalls," etc.

It would also be interesting to know where the experiments were conducted. In liberal areas of the country where people believe politicians' promises? In conservative areas of the country, where people believe a different set of politicians' promises? Or in areas where the government has clearly betrayed the trust of the people, and people believe a smaller-than-normal subset of the politicians' impossible promises? Just because a charity (or a politician) promises to do X doesn't mean that X will get done.

Perhaps simply by asking two questions about two different groups of numbers, which form two different ratios, the people become more concerned with what the numbers might mean. This is rational concern with "details of a problem" and it is also rationally "less concern with details than with other more pressing problems." Moreover, thinking is difficult for most people. To deal with (devote optimal brain space to) ANY problem other than the "most important" problems (optimal diet, optimal governance, optimal clothing, furtherance of rationally-chosen top-importance plan, etc.) is irrational.

For this reason, I wonder if the researchers asked the people if they had their undivided attention, and down-ranked those who admitted they were not able to pay full attention. Moreover, could those who paid full attention have "less on their plate," and (therefore) be less rational overall? (The guy who lounges around a University library has less on his plate than the professor hurrying to give a lecture. Did these studies take place on university campuses? Did they take place in the city? In the country? All of the prior? How were they controlled?)

Most people lack anything resembling a consistent philosophy. Some have more rational biases and heuristics than others. The use of heuristics isn't entirely irrational, given how "unwittingly destructive" most people are, by default.

I don't necessarily doubt that some people feel better about "solving a larger part of a whole problem" without a rational choice of scope or scale. Still others might react the opposite way, based on marketing. It's been my experience that most people are generally incapable of evaluating high-hierarchical-level philosophical ideas on their own merits. They tend to judge "numbers of points in favor" vs. "number of arguments against" without properly assessing each argument for its relative weight.

Additionally, the larger number (250,000) might then force the person into thinking about large numbers of people for whom a contribution could help, forcing them to think about ...the country they live in. The 4,500/11,000 sounds like an anomaly, the 4,500/250,000 sounds like a small minority out of a large majority. Most social training trains people to be rather insensitive to minorities, and to accept that they "cannot save everyone." So, the person who is focused on 250,000 might as well focus on the minorities they could help in their own town, city, or state of 250,000. ...But that's not part of the study. (Or is it addressed by the study? I admit I didn't read up on the study.)

Still, very interesting. I'll have to look at it more to see if I believe it's applying scope restrictions to problems that don't merit them.

Vegetarianism is similar. I know many vegetarians who only think about the poor cow who now is served as dinner instead of the thousands of animals who are killed by pesticides, fertilizers, and mechanized farming equipment needed to grow a bowl of soy beans.

We should not make decisions based on emotional reactions. They do not scale.

I haven't read the studies. I'd like your opinion on the following idea. Could it be that the way to ask the question relates to the type of curve you get? Could you lead someone to come up with a linear ramp-up of money?

Also: how does the amount the subjects stated compare to the actual cost? If I have to save one bird, it might cost me a few hundred dollars in travel expenses, etc. But saving two birds is only slightly more.

Actually scope insensitivity might be a species-wide positive adaptation. It is more economical to rescue 200,000 birds for $88 and this could reflect a reasonable expectation of economies of scale.