Cost-benefit analysis can increase trust in decision makers

Jonathan Baron1
University of Pennsylvania, Andrea D. Gurmankin
Rutgers University


Four experiments on the World Wide Web asked whether people trust an agent (a company or government agency) more when the agent uses cost-benefit analysis (CBA) or, more generally, bases decisions on their consequences. Experiment 1 used a scenario concerning the installation of a safety device in a car. The decision was made either by a company or a government regulatory agency. Trust in the agent increased when the decision made was consistent with the results of CBA. Part of the CBA involved comparison with other safety devices that were either installed or not. Such comparison increased trust even when the subject disagreed with the agent's decision. Experiment 2 replicated Experiment 1 with a health-care scenario involving decisions by insurance companies about whether to cover a treatment. Experiment 3 showed that trust could be increased by CBA even in highly charged moral contexts. Experiment 4 found that people are willing to take cost into account more for social decisions than for individual ones. The results together suggest that people might be responsive to clear justifications of policies that emphasize costs, benefits, and alternatives, even if these policies violate their intuitions.


Government regulatory agencies, courts, health insurers, and other institutions sometimes try to adopt policies that bring about the best overall outcomes, all things considered. In trying to do this, they often use cost-benefit analysis (CBA) or some other form of formal analysis based on the costs and benefits of expected consequences. They may measure the consequences in terms of money, life years, or utility. When agencies (in this general sense) attempt to use CBA (likewise in a general sense, including other forms of decision analysis), they often face opposition, because people's intuitions are often inconsistent with the results of CBA. If agencies are to succeed in their efforts to improve outcomes, then people must trust the agencies even when their policies are counter-intuitive. Can people come to trust agencies that make decisions consistent with CBA, despite the conflict with their intuition?
Breyer (1993) argues that regulation of risk is hampered by a cycle in which the public reacts to some incident, such as Love Canal (Kuran & Sunstein, 1999), the government passes some poorly crafted legislation in response to public reaction, such as the Superfund laws, and the legislation itself provokes a counter-reaction, and the cycle continues. If the agencies were trusted more, Breyer argues, the legislature would give them broader scope, and they could regulate in the public interest. In order to be trusted more, they must earn that trust: "Trust in institutions arises not simply as a result of openness in government, responses to local interest groups, or priorities emphasized in the press - though these attitudes and actions play an important role - but also from those institutions' doing a difficult job well" (p. 81).
Breyer's solution is to develop, over time, a branch of the bureaucracy that is in fact competent and expert in making decisions according to their consequences and is also perceived as being competent and expert. Bureaucrats in such a branch must be competitively selected, well trained, and insulated from outside pressure. Although Breyer does not mention it, the current U.S. Federal Reserve may be a case in point (at least until the next economic disaster). The control of interest rates in the U.S. used to be heavily politicized, but now most citizens (and legislators) seem to trust the Federal Reserve to try to control interest rates in the public interest.
However, good decisions, that is, those that are in the public interest, may not always be perceived as good decisions. Public perceptions of risk seem to be influenced by intuitive judgments that disagree with those that experts might make according to CBA. Such intuitive judgments are often based on principles other than those designed to bring about the best consequences. Risk experts, of the sort that might serve in a Breyer-type regulatory branch, are likely to be trained in welfare economics, decision theory, and cost-effectiveness analysis. These disciplines are based on theories about how to achieve the best consequences (or why the best consequences are not achieved). In the case of risk regulation, the best consequences amount to minimizing harm for a fixed cost, or minimizing cost for a given level of harm, or minimizing some weighted sum of cost and harm. "Harm" may amount to something as simple as lost years of life (or lost quality-adjusted years).
Currently, regulatory agencies, courts, and health-care providers rarely rely on CBA. Thus, from the perspective of CBA, we could do more good with less money than we are now doing. (See, for example: Slovic, 1998; Tengs et al., 1995.) Psychological research suggests that inefficient decisions of these agencies are based to some extent on the nature of human judgments. On a number of issues, people's intuitive judgments are biased systematically away from the recommendations of CBA (Baron, 1998, 2000), such as the preference for harms of omission over harms of commission. When acted on, such biases (away from maximization of consequences) can cause worse outcomes. If we are concerned with improving outcomes, then we might want to examine the role of these effects in decision making.
As a result of such judgments, agencies are often put in a conflict between the intuitions of their clients and the advice of technical experts, who usually base their recommendations on an analysis of consequences. This applies to such agencies as the U.S. Food and Drug Administration (FDA) and the Environmental Protection Administration (EPA). For example, EPA has recently been taking into account the distribution of risk as well as its total amount, thus siding with popular intuition. FDA may have done the same in its recent decision to withdraw the rotavirus vaccine. At an individual level, doctors who recommend DPT vaccine are often caught in the same bind.
One way an agency might deal with such intuitions or biases is to attempt to explain its actions, especially when they are consistent with CBA but inconsistent with public opinion. Can this help? The experiments reported here attempt to simulate the effects of various types of CBA on trust.

Experiment 1

Viscusi (2000) asked juror-eligible citizens in the U.S. whether they would assess punitive damages against a car company that decided not to make safety improvements in a car's electrical system, leading to deaths from burns, and, if they would assess punitive damages, how much. When the company had carried out a CBA to make the decision about making the safety improvements, the proportion of subjects who assessed punitive damages was no lower than when the company did not carry out the CBA (even slightly higher). The analysis assigned a value to human life, and raising this value up to $4,000,000 per life had no effect. In fact, subjects assessed higher punitive damage awards when the value of life was higher, apparently because they anchored on the number given.
Viscusi's result is discouraging for the proponents of the use of CBA by corporations and government. It suggests that when a company uses such an analysis is used to justify inaction in a case like this, it will make people no more forgiving of the company.
Viscusi gave the scenarios with and without analysis to different subjects. Such a between-subject design lacks statistical power, and it may have missed detecting an effect even with several hundred subjects. Of course, it did detect the anchoring effect with the value of life, but that effect involved a numerical response, and the main analysis was simply whether or not punitive damages were assessed. The experiment may have been insensitive because the probability of awarding some damages was on the order or 90% overall, leaving little room for effects of experimental manipulations.
Experiment 1 used a more sensitive design to assess responses to CBA in the same context. It manipulated several variables concerning the type of analysis done, and whether the final decision is consistent with the analysis. It asked about trust in the agency or company that did (or did not do) the CBA, and about fines in case of injury. The fines serve as a second, more concrete, measure of the extent to which the agency is at fault. The general result is that, when the decision is consistent with the analysis, CBA increases trust and reduces fines assigned for mishaps, regardless of whether the decision suggested by CBA is consistent with the subject's judgment.


Ninety-five subjects completed a questionnaire on the World Wide Web. Their ages ranged from 18 to 74 (median 34); 26% were male; 9% were students. The questionnaire began:
Safety features
This questionnaire concerns the trade-off between money and safety. Governments and corporations are faced with choices, in which they can spend more money and reduce risk.
The safety issues concern prevention of injuries and death. We shall give the number of "serious injuries" in each case. All serious injuries require hospitalization. Half of these injuries result in some permanent disability, and 10% result in death.
The cost of prevention is paid by consumers. For example, if a safety device is put in a car, the price of the car increases by the cost of the device.
The questions ask what you would do in such cases, and also how much you would trust government agencies or corporations that made various choices.
Some items ask you to compare two government agencies, concerned with safety regulation. Imagine that either of these agencies could make a regulation about the device in question. Also, imagine that these agencies could be sued in court, just as corporations can be sued.
We are interested in what reasons you think are relevant to these decisions, so please pay attention to the different reasons.
Each screen involved a comparison of two agents (corporations or agencies). The first agent always based the decision on cost alone. The second agent based the decision on benefit as well as cost (although the decision was the same). On half of the cases, the second agent also compared the device in question to other devices. The wording read, with alternatives and noted in brackets:
Consider a safety device for cars. Its cost is $50 per car, and it would increase the car's price by $50. Its benefit is that it would prevent 50 [5] serious injuries, for 200,000 drivers. It would reduce each driver's chance of injury by .025 [.0025] % over the lifetime of the car.
Other safety features not [now] installed in cars could prevent injuries at a lower [higher] cost per injury prevented.
Should the government require [Should a company install] the device?
Probably not
Definitely not
Agency [or Company, throughout] A decided [not] to require that the device be installed [install the device]. Agency A knew the cost of the device, but it did not try to discover the benefit of the device (the number of serious injuries prevented, which you were told above). Agency A based its decision on cost alone.
Agency B also decided [not] to require that the device be installed [install the device]. Agency B did discover the benefit (the number of serious injuries prevented) as well as the cost. Agency B based its decision on the average cost of preventing each serious injury.
Agency B did not attempt to compare the costs and benefits of this device to other safety features already installed in cars that prevent injuries at a higher or lower cost per injury prevented.
[For half of the cases, the last two sentences were:] Agency B also determined that other safety features [not] installed in cars can prevent injuries at a higher [lower] cost per injury prevented.
Which agency would you trust more to make decisions like this in the future?

A much more
A a little more
B a little more
B much more
[If the device was not installed, the following was asked:] Suppose both agencies were sued in court because they did not require that the device be installed. Injuries occurred that the device would have prevented. The law says that the maximum payment to victims is $1,000,000 per injury. How much should each Agency pay each victim (in thousands of dollars, digits only)?
Agency A $        Agency B $
The 32 screens were presented in a different random order for each subject. Each screen described two agents (decision makers). The 32 screens represented all possible combinations of two levels of each of five variables:
  1. Government agency vs. private company as the agent (manipulated mainly to increase the number of cases per subject);

  2. Benefit of the safety device (5 vs. 50 serious injuries);

  3. Whether the device was to be installed or not (the same for both agencies);

  4. Whether the device had a higher cost-effectiveness than other devices now installed vs. a lower cost-effectiveness than other devices not installed (betterness);

  5. Whether the second agent had determined #4 or not (knowledge).

Note that #4 implied either that the device was probably worth installing, since it was more cost-effective than other devices installed, or that it was not worth installing, because it would be more cost-effective to install some other device. Thus, this manipulation put the decision in a larger context, as a more thorough CBA would do.


Because the design was within-subject, all analyses are based on t tests of contrasts or interactions (differences of differences).

Whether the device should be installed

Consider first the question about whether the device should be installed (Should-install). On the average, subjects favored the installation of the device, with a mean score of 0.31 (which differs from 0; t94=5.11, p=.0000) on a scale where 0 is neutrality and each step on the answer scale is 1 unit (so that "probably" is .50, and "certainly not" is -1.5).
Should-install was sensitive to the benefit (.45 with 50 injuries, .17 with 5; t=6.55, p=.0000), although 47% of the subjects showed either no effect or a (small) reversed effect. (Some of this 47% favored the device very strongly regardless of the benefits.)
Should-install was also sensitive to the implications of comparisons to devices installed or not installed (.58 when less cost-effective devices installed, .05 when more cost-effective devices not installed; t=6.92, p=.0000; 31% showing no effect or a small reversal). Call this the effect of "betterness."2


We ask two questions about trust. First, do people trust the agent that considers both benefit and cost (B) more than the agent that considers only cost (A)? This is the simplest question about whether CBA increases trust. Second, is trust affected by whether B act's consistently with the results of the analysis?
On the first question, Table shows the means for trust in the agent that did the more thorough analysis (B). Agent B examined both benefits and cost while agent (A) examined only cost. The two agents on each screen always made the same decision. The fact that these numbers are positive indicates that subjects were more inclined to trust the more thorough agent (B); the mean rating was .68 on a scale where each step is 1 unit and 0 is neutrality (t=13.03, p=.0000).3
Table 1: Trust in B, the more thorough agent (0 is neutrality).

Not installed Installed
No knowledge Knowledge No knowledge Knowledge
5 lives, worse 0.43 0.85 0.62 0.77
50 lives, worse 0.43 0.82 0.73 0.79
5 lives, better 0.46 0.53 0.62 1.03
50 lives, better 0.39 0.48 0.75 1.13
Turning to the second question, about consistent action, the size of the benefit (number of lives saved) should affect the desirability of installing the device and should thus interact with whether the device is installed. B should be more trusted when B is responsive to benefit. Although size of the benefit did not have a significant main effect, higher benefit leads to more trust when the device is installed than when it is not installed (t=2.71, p=.0079).
Betterness - whether the device was better (in cost-effectiveness) than installed devices vs. worse than uninstalled ones - also had no main effect. Betterness should increase trust when B knows about it and acts on it. Thus, it should interact with knowledge and installation.
Knowledge - whether the agency knew about betterness - increased trust (t=7.09, p=.0000). Knowledge did not interact with installation, betterness, or benefit. However the expected triple interaction between knowledge, betterness, and installation was significant (t=5.66, p=.0000). Knowledge led to the highest trust when the device was better than other devices and when it was installed (lower right of Table 1). When the device was better and not installed, knowledge did not affect trust significantly either way. Importantly, though, knowledge led to increased trust when the device was worse and was not installed (the upper left of the table; t=7.62, p=.0000). In sum, the agency earned more trust when they attended to comparative information and followed its implications.
In sum, knowledge about betterness increase trust in decisions that are consistent with that knowledge. Does this effect happen even when the subject disagrees with the agency's decision? To test this, we examined pairs of cases (screens) that differed only in knowledge. We selected those pairs in which the subject disagreed with the agency's decisions in both cases. (25 subjects had no such pairs.) Knowledge led to greater trust even within these pairs (mean effect of 0.34, t69=5.04, p=0.0000).


In cases where the agency or company described did not install the device, we asked about fines (with a maximum of $1,000,000 per injury). The mean fine for agent A (no analysis of benefit) was $504,000, and the mean for B was $440,000. The range of fines was high, however. To get a better measure of the relative fines for A and B, we computed the ratio 2A/(A+B)-1, which would be 1 if the subject fined agent A and did not fine B, -1 if the subject fined B but not A, and 0 if the fines were equal. (Fines of 0 for both were treated as missing data.) The mean of this measure, 0.098, was positive (t93=5.00, p=.0000), indicating that more analysis led to lower fines.4
Table shows how this measure depended on knowledge, benefit, and betterness. Recall that the measure is higher when agent B, the one who does more analysis, is fined less for not installing the device. It is thus parallel to the measure of trust in B, when B does not install the device.
Table 2: Relative fine for A (no analysis) vs. B (1 if all for A, -1 if all B).

No knowledge Knowledge
5 lives, worse 0.101 0.162
50 lives, worse 0.066 0.173
5 lives, better 0.071 0.069
50 lives, better 0.099 0.048
The measure was higher (B fined less) when the uninstalled device was worse compared to the alternatives (t = 3.71, p = 0.0004), when it had less benefit (t = 1.85, p = 0.0677), and when B had knowledge of this (right column vs. left, t = 4.12, p = .0001).
Of greater interest is the interaction between knowledge and betterness (t93=3.17, p=0.0021). The effect of betterness (top two rows vs. bottom two rows in Table 2) was greatest when B was informed about it.5 In sum, appropriate use of CBA reduces fines. The results parallel those for the trust measure.

Does the effect work with all subjects?

It is possible that - despite the main effect of increased trust in those who use CBA - some subjects distrust CBA so much that it reduces their trust. Clearly this did not happen with most of our subjects, as the overall effect was to increase trust. To examine individual differences, we carried out a one-tailed t test for each subject in "trust in agent B." The test was one tailed because we were looking only for subjects who trusted B less than A. But, of course, with enough subjects, some of these tests would be significant by chance alone. Thus, we examined adjusted p-levels for multiple tests. We used the step-down resampling procedure of Westfall and Young (1993) as implemented by Dudoit and Ge (2003). By this test, 2 subjects showed significantly greater trust in agent A at p < .05 (one tailed - p=.0223 for both). Thus, CBA reduces trust for some people, but not for very many in our population.

Experiment 2: Health insurance

Experiment 2 replicated Experiment 1 in the context of health insurance.


One hundred and two subjects completed a questionnaire on the World Wide Web. Their ages ranged from 18 to 74 (median 35); 28% were male; 15% were students. The questionnaire began:
Health insurance
This questionnaire concerns the trade-off between money and health. Health insurance companies must decide which treatments to cover (pay for).
On each screen, you will see some information about a cure for a serious disease. Suppose that all diseases are quite serious and chronic, making for a low quality of life and usually a shorter life too. Examples are diseases like severe arthritis, senility, emphysema, and heart disease.
The treatments work with one type of each disease, so they are given only to people with that type. Once the patient is diagnosed as having that type of disease, the treatment is given all in one dose of a drug. The drugs are expensive because of the methods needed to produce them.
You will see:
You will also see information about two different insurance companies and how they decided whether or not to cover the treatment. We are interested in what reasons you think are relevant to these decisions, so please pay attention to the different reasons.
You will be asked
The wording of the items read [with alternatives in brackets]:
Should insurance companies cover the treatment?
Probably not
Certainly not
Company A decided [not] to cover the treatment. Company A knew the cost of the treatment for each policy, but it did not try to discover the benefit of the treatment (the percent of cures, which you were told above). Company A based its decision on cost alone.
Company B also decided [not] to cover the treatment. Company B did discover the benefit (the percent of cures) as well as the cost.
Company B based its decision on the cost per cure. Company B did not attempt to compare the costs and benefits of this treatment to other treatments that it currently covered or did not cover.
[Company B also determined that other treatments that it did NOT cover currently [currently covered] could cure more [less] serious diseases at a LOWER [HIGHER] cost per cure.]
On the basis of this information alone, how would you feel about having insurance from Company A

Very pleased
Very displeased
On the basis of this information alone, how would you feel about having insurance from Company B

Very pleased
Very displeased
Which company would you trust more to make decisions like this in the future?
A much more
A a little more
B a little more
B much more
Each subject saw all combinations of the five variables in a different random order. The variables were: Cost, Cure rate, Coverage (whether A and B covered the treatment or not), Better (whether the treatment was better than alternatives in terms of cost and effectiveness, or worse in terms of both), Compare (whether the company compared the option to alternatives). The premium increase was derived from Cost and Cure rate.


In general, subjects favor decisions that are consistent with a CBA. The measure Should-cover, the subject's opinion about whether coverage should be offered, was defined so that 0 was neutrality and each step on the scale was one unit. The means of Should-cover depended on Cure (.65 for 100%, .11 for 50%), Cost (.02 for high cost, .65 for low), and Better (.52 for Better, .16 for Worse). All differences were highly significant (p=.0000), and no interaction was significant.
Table shows the means for Feelsum, the sum of the two measures of how the subject felt about the two companies. Both made the same decision, so this serves as an overall measure of confidence in that decision. All of the first-order interactions shown were highly significant (p=.0000): subjects favored coverage more (larger difference between Not cover and Cover) when the treatment was lower cost, when it cured 100%, and when it was the Better option. No higher-order interaction was significant.
Table 3: Means for Feelsum, the sum of how subjects felt about the decision, as a function of cost, coverage, benefit and betterness.

Not cover Cover
High cost -0.45 -0.24
Low cost -1.13 0.59
50% cure -0.61 -0.04
100% cure -0.98 0.39
Worse -0.51 -0.15
Better -1.07 0.50
Table shows the results for the questions about how the subjects would feel about getting insurance from the two companies, coded so that positive numbers represent better feelings about B (the more thorough company). Here we could also assess the interaction of Cost, Cure and Betterness with Coverage. The interaction between Cost and Cover was significant (t101=2.55, p=0.0122), as was that between Better and Cover (t101=4.87, p=0.0000), but the interaction between Cure and Cover was not significant. In general, though, people feel better about B, the more thorough company, when it is responsive to Cost and Betterness.
There was also a triple interaction between Betterness, Comparing, and Coverage (t101=5.89, p=0.0000). This is what we would expect if the increased trust resulting from responsiveness to Betterness were found mainly when Company B made the comparison so that it knew about Betterness. In other words, Betterness affects trust only when Company B took the trouble to find out about betterness.
Table 4: Differences in feeling about Company A and B, with positive numbers indicating better feeling about B (the more thorough company).

Not compare Compare
Not cover Cover Not cover Cover
High cost 0.17 0.27 0.45 0.53
Low cost 0.17 0.30 0.38 0.65
50% cure 0.16 0.29 0.45 0.55
100% cure 0.19 0.28 0.38 0.63
Worse 0.17 0.30 0.69 0.45
Better 0.18 0.27 0.14 0.73
Table shows a parallel analysis for Trust, the question about whether the subject would trust B more than A. In this case, the interactions with Coverage were all significant: Cost (t101=3.61, p=0.0005); Cure (t101=2.13, p=0.0353); and Better (t101=4.87, p=0.0000). Again, the triple interaction between Betterness, Comparison, and Coverage was significant (t101=6.53, p=0.0000).
Table 5: Differences in trust in Company A and B, with positive numbers indicating more trust for B (the more thorough company).

Not compare Compare
Not cover Cover Not cover Cover
High cost 0.22 0.26 0.42 0.49
Low cost 0.18 0.34 0.38 0.65
50% cure 0.18 0.28 0.43 0.50
100% cure 0.22 0.31 0.38 0.64
Worse 0.19 0.29 0.66 0.42
Better 0.21 0.31 0.14 0.72
Again, the main results so far are consistent with the general conclusion that trust increases when the decision maker adopts a strategy of doing thorough analysis and following its conclusions. Again, we asked whether such a strategy is effective even when the subject disagrees with the decision to which it leads, which was the same for both companies in each case. Knowledge increased trust in Company B (the more thorough company) when the decision was consistent with betterness (better and covered, worse and not covered) even on just those pairs of cases in which the subject disagreed with the agent's decision in both cases in the pair (mean effect of 0.27, t84=3.66, p=0.0004).
In this study, 6 subjects (6%) were significantly more trusting of the company that did less analysis (A), after correcting for multiple tests as in Experiment 1. As in Experiment 1, the attempt to use the results of CBA in the context of health coverage can actually reduce trust for some people. The number is small enough, however, so that it seems unlikely to become a majority even with a different method of sampling.6

Experiment 3

The present experiment examines the effect of CBA on trust in a more morally charged context. Subjects were presented with items found in other studies to be morally objectionable even though they might conceivably lead to good outcomes, such as cloning. Many people think that cloning (for example) should be completely prohibited. We asked whether they could trust a government agency that would not prohibit it, if a CBA indicated that cloning was useful in some cases. Of course, a demonstration that a procedure is sometimes useful does not necessarily imply that an agency could craft a rule that would permit it when it was useful and prohibit it otherwise, but such a demonstration would provide some justification for not banning the procedure totally. Are people responsive to such a justification?


One hundred and five subjects completed a questionnaire on the World Wide Web. Their ages ranged from 20 to 74 (median 38); 27% were male; 13% were students. The questionnaire began:
Medical procedures
This questionnaire concerns some medical procedures that have been much in the news recently, such as cloning. One issue is whether qualified doctors should be allowed to do them if patients want them.
Please assume that all of these procedures have been perfected so that they are completely safe and have their intended effect.
[There were then some brief definitions of terms used in the cases: artificial insemination, cloning, in-vitro fertilization, embryonic stem cells, Alzheimer's disease, prenatal genetic testing, spina bifida.]
Many people object to procedures like cloning or abortion on moral grounds. Note that you can object to a procedure on moral grounds and still think that someone might benefit from it. Some questions may require you to imagine this kind of conflict situation.
Each item began with one of the following 16 procedures (the numbers in brackets are mean responses to ALLOW, TRUST, and CBA questions, respectively, as explained later).
The items were presented in a random order chosen separately for each subject, twice (in the same order for each subject - so that some questions were maximally far apart). The subject answered 4 questions in the first pass and five in the second pass. Here I present only the questions relevant to this article (ALLOW in the first pass, the others in the second):
ALLOW. Should the government allow this procedure? [Response options: This should be allowed, so long as other laws are followed. This should sometimes be allowed, with safeguards against abuse. This should never be allowed, no matter how great the need.]
TRUST. Suppose two government agencies could have the power to decide which medical procedures are prohibited. The two agencies are similar, but agency P would prohibit this procedure completely and agency N would not. Which agency would you trust more to have the power to decide? [P; N]
CBA. Suppose that a team of economists and other researchers did an analysis of the effect of allowing this procedure under certain circumstances. The team reported that the procedure could do some good in these circumstances, and nobody would be harmed. In this case, which agency would you then think should have the power to decide about prohibition? Remember, agency P would prohibit this procedure and agency N would not. [P; N]


The mean answers to the ALLOW, TRUST, and CBA questions for each item are shown above in brackets, respectively. ALLOW was scored so that 1 favored allowing and -1 favored prohibition (with 0 representing "sometimes"). TRUST and CBA were scored so that 1 represented N (not prohibit) and -1 represented P (prohibit). The main result was that CBA responses (empowerment after the CBA showed benefit) were higher than TRUST responses (before the CBA; t104=4.17, p=0.0001; the result was also in the same direction for all but one of the items). In sum, subjects were more willing to trust - i.e., give power to - an agency that would allow the procedure when they were told that the a CBA had shown that the procedure could be beneficial on the whole.
Again, we asked whether any subjects showed significantly less trust with CBA than without it, the opposite result from that just reported. In this case, no subject showed a significant reversal.

Experiment 4: efficiency for social vs. individual decisions

CBA is often criticized for being concerned with efficiency at the expense of individual welfare. In the trade-off between cost and benefit of medical treatments, for example, people may think that they should get an effective treatment even if it is extremely expensive. Yet many agencies want to impose some sort of rationing based on CBA, and such rationing has been found to strike many as unfair or immoral (Ubel, 2000). If people want agencies to follow their individual preferences, they will oppose any effort to ration expensive treatment. If, on the other hand, people accept the need for rationing at a societal level, they may tolerate it as a matter of policy, even if they would not want it for themselves.
The last experiment compared decisions about the self to two types of policy decisions: decisions about voting, and decisions about which agency to trust. We hypothesized that self decisions would favor greater benefit at the expense of greater cost, compared to the two societal level decisions.
Note that this is not necessarily a matter of selfishness, although it may appear that way to the subjects. When treatments are provided by government or by insurers, someone must pay for them, and the payers are ultimately the same people as those who might need the treatment (at least over a range of treatments - e.g., women do not get testicular cancer, but they do get breast cancer more than men do). The situations described were sufficiently general so that subjects had no good reason to think that they would benefit more than would others, or pay less than others, from a decision to provide an expensive treatment.
Likewise, acceptance of rationing would not make people less altruistic, in a formal sense. Instead, true altruism would consider both the health benefits and costs for others. If people thought that others were like themselves, perfect altruism would lead to the same preferences for self and others. Subjects in this experiment are asked to assume that they are typical.7 If subjects are more inclined to choose cost-effectiveness in policy than for themselves, we can think of this (formally described) as a kind of differential altruism, in which they express more concern for others' finances than for others' health, relative to what they want for themselves.
We hypothesize, however, that people will think differently about the individual case because of the "identifiable victim effect" (Jenni & Loewenstein, 1997; see also Baron, 1997, for a related result). They tend to think of the benefit to individuals, themselves, as solving a single problem, that of the individual, with the cost spread over millions of people, each of whom does not notice the difference.
Alternatively, the same result could arise from a kind of misguided selfishness, in which people mistakenly think about the benefit and not the cost when thinking about themselves, even though the social decision involves the identical trade-off, on the average, for everyone. Our experiment does not distinguish these explanations, but it does show that people may accept rationing by CBA at a policy level even when they oppose its implications for themselves.


One hundred and seventy-eight subjects completed the questionnaire (ages 18-67, median 38); 30% were male; and 12% were students.
This questionnaire concerns decisions about medical treatments for one-time epidemics of new infectious diseases. The question is what to do if the epidemic hits.
The diseases in question all have fatality rates of 10%. Each disease will affect 1% of the population, without regard to age, sex, race, or health status.
Nothing can be done to prevent infection. Everyone is equally at risk. Thus, each person has a 1/1000 chance of death, unless treatment is available.
There are 32 screens, each with 4 questions. Some screens may look the same as others. They are not. The numbers are different. Please pay attention to the numbers.
Some questions concern your own choices for yourself, and others concern your nation. Imagine that you are typical of your nation in terms of your ability to pay.
One question concerns the relative strengths of two arguments. I am interested in cases where the relevance of an argument depends on the kind of decision you are making. For example, some arguments may be more relevant to decisions about yourself, or other arguments may be more relevant to decisions about your nation. Please read these carefully.
Suppose that your nation has both private health insurance and government coverage for at least some treatments. Some questions concern private insurance, and others concern government payment.
[Here is an example of an item:]
The government will pay for the treatment for all who get the disease.
Treatment X cures 100% at a cost of $50,000 per case treated - $5,000,000 per life saved. The source of the money will be determined later.
Treatment Y cures 50% at a cost of $8,000 per case treated - $1,600,000 per life saved. The source of the money will be determined later.
[Subjects did not see the names of the questions]
1. [Vote] Suppose the national government had to decide on X or Y, and it has a vote (as part of another election). Which would you vote for? ('Equal' means that you would abstain on this question.) [X Y Equal]
2. [Trust] Suppose that two candidates in this national election argue for different treatments.
Candidate X argues for X because it cures the most people.
Y argues for Y because it is the most cost effective.
Based on this information alone, which candidate would you trust the most to make decisions like this in the future (on his/her own)?
3. [Self] How would you choose between X and Y for yourself? (Suppose you are typical of those affected in questions 1 and 2, in your ability to pay.)
[The treatments were repeated as a reminder.]
4. Note that treatment X cures the most people, and treatment Y is the most cost effective. Consider the relative strength of these arguments.
Which argument is more relevant to each type of decision?
The 32 items varied in whether the method of payment was determined later (as in the example) or paid by those affected, in which case the item read, "Your taxes [insurance premium] will increase by [the cost per case treated divided by 100] for one year." The purpose of this variation was to test the hypothesis that people would be more willing to pay for something when the source of the payment was unspecified. Otherwise, we wanted to make clear that those who might need the treatment would collectively pay for it, one way or another.
The items also varied in whether the treatment was provided by government or insurance, and, orthogonally, in the cost of Treatment X, the high-cost condition, which was either $50,000 (as in the example above) or $100,000 per treatment. (The low-cost condition cost was always $8,000.)
Finally, there were four different price conditions, included largely to create variation so that we could collect more data from each subject:
  1. The high-cost treatment was 100% successful and the low-cost treatment was 50% successful.

  2. 50% and 25% success, respectively, with the cost of each treatment divided by two so that the cost per life saved was the same as in condition 1.

  3. 100% and 25%, respectively, with the cost of the low-cost treatment divided by two, again holding constant the cost per life saved.

  4. The same as condition 1, but with all costs divided by 10 (so that even the high-cost treatment was within the usual accepted range).


Figure shows the proportion of responses of each type - favoring the expensive treatment (X), favoring the efficient treatment (Y), equal - as a function of the question. The main result is that, as hypothesized, the Trust question (Which candidate would you trust?) and the Vote question (Which treatment would you vote for?) each yielded more support for efficiency than did the Self question (Which treatment would you choose for yourself?). When responses were coded as 1 for expensive and -1 for efficient, and the mean for each subject was computed for the 32 questions, Self was higher than Vote (t177=5.02, p=0.0000), and Self was higher than Trust (t177=3.00, p=0.0031). (The Vote-Trust difference was also significant, but we had no hypothesis about it.) In sum, people were more accepting of efficiency considerations for policy than for themselves.
Figure 1: Proportion of responses of each type as a function of the question.

These results were equally strong (and both significant) when the case involved payment as when the source of funding was unspecified. (The interactions with pay were approximately zero.) In the pay condition, the cost to the taxpayer or policy holder was the same, and specified, for all questions. We do not take this lack of effect as a definitive refutation of the hypothesis that people are more willing to demand costly policies when the source of payment is unspecified. Rather, the within-subject design may have led subjects to realize that, indeed, someone has to pay.
Some subjects showed the reverse effects. The self-trust difference was significantly negative (less expensive favored more in the question about self than trust in an agency) for 7% of the subjects. The same percentage showed a reversed effect for the self-vote difference. Possibly these subjects did not want to withhold an expensive treatment from others out of stinginess about paying for it, even though they would be unwilling to pay for it (through insurance) for themselves.
Question 4 concerned the relative strength of arguments about cure rates and cost-effectiveness. On the average, more responses indicated that the cure-rate argument was more relevant to the self and the cost-effectiveness argument was more relevant to the government than the reverse (t177=5.45, p=0.0000, across subjects). (Three subjects, in comments, said they had trouble understanding this question.) 55% of the subjects showed a significant positive effect (cure-rate more relevant to self) and 21% showed a significant reverse effect. The mean response to Question 4 correlated .34 (p=.0000) with the self-vote difference.
The different attitude toward the self was reflected in several comments. Here are two of the longer ones: "Most all of my answers were the same here. The reason for this was because when deciding for myself, I will always choose the moral decision of deciding to save the most lives. When it comes to putting some one in charge of making the decisions for me, I feel that the person making the cost effective choice is the best for the economy. Although saving lives seems to be the most ethical, if we have medical expenses rise that much, our budget will all be out of whack." "I think anytime we can cure more people it should be done unless determined too expensive is my view for nation. As for myself I will always want the one that cures the most, it may be bad to look at it that way but I suppose it's like running a business with the nation and with myself there is no room for debate. I want the one that cures the most regardless."
Twenty percent of the subjects consistently chose the more expensive treatment in all conditions. Typical of their comments was, "I would not consider cost effectiveness when trying to save lives." No subject consistently chose the more cost-effective treatment.
The different cure-rate/price conditions were included mainly to get more data and to create conditions that might lead to within-subject variability. However, one result of interest was that the expensive treatment was chosen more often in the third conditions, with cure rates of 100% for the expensive treatment vs. 25% for the efficient one, than in either of the first two conditions (100% vs. 50%, 50% vs. 25%). Averaging across all three measures (Vote, Self, Trust), the mean responses (with 1 favoring the expensive treatment) were .33, .32, .54, and .75, for the four cure-rate/price conditions, respectively. The third was significantly greater than either of the first two at p=.0000 by t test for every comparison. Subjects seem to be influenced by the large difference in cure rate, even though it is balanced by a large difference in cost. The fourth condition represented a lower cost for all treatments, and the responses were higher than those of all other conditions, as they should be by any account.


The results of Experiments 1 and 2 support the view that CBA, when it involves comparison to alternatives and when its results are acted upon, can increase trust in decisions. Although Viscusi (2000) suggested the opposite, his results were weak statistically, and many of them were limited to the very few subjects who were least inclined to award punitive damages, as almost all of his subjects did award such damages in all conditions, leaving little room for any effects. In addition, as Viscusi points out, the sizes of damage awards in his study may have been larger with a larger value of life because subjects anchored on the value when determining their award. The present within-subject design apparently reduced such an anchoring effect, so that the benefits of CBA could be seen.
Of interest in these experiments is that CBA increased trust even when the subject disagreed with its conclusion. Thus, CBA can apparently help win trust even among those who disagree with the policy that is adopted, provided that people are adequately informed about the basic reasoning behind the CBA.
Experiment 3 showed that trust could be increased by CBA, even in highly charged moral contexts.
Experiment 4 found that people accept rationing on the basis of cost more for social decisions than for individual ones. It is not clear here which option is the true optimum in terms of utility. (Health and life may be worth more than people are willing to pay for them at a societal level.) People may feel that their own life is worth more than the lives of others, but the insurance context of the experiment implies that they would be paying for others anyway. If they truly understand that insurance implies that everyone pays and everyone (potentially) benefits, then we could take their Self judgments as being "real." People may not fully understand, however. When they answer about themselves, they may focus on the idea that one person is benefiting while everyone is paying. And they may think, "For myself, cost is no object," without realizing that their endorsement of this view implies the same for everyone.
It is also not clear whether CBA in general, properly done, favors more spending or less on health care than is now spent, but at some point CBA will limit spending. The experiment indicates that people are willing to take cost into account, as well as benefits, when evaluating a policy that affects many people.
The use of a within-subject design had the main purpose of increasing the statistical power of these studies, but it may also have been unrealistic. Arguably, some decisions are made without any comparison, such as the assignment of punitive damages in legal cases. On the other hand, other real cases may be modeled better by a within-subject design, such as a change in policy. When an agency or company announces that it is going to start doing CBA, people will naturally evaluate this change by comparing the situation before the change with the situation after it. Our results suggest that people will, in general, perceive the adoption of CBA as a good thing.


Babcock, L., Gelfand, M., Small, D., & Stayn, H. (2003). The propensity to initiate negotiations: toward a broader understanding of negotiation behavior. Under review. Baron, J. (1995). Blind justice: Fairness to groups and the do-no-harm principle. Journal of Behavioral Decision Making, 8, 71-83.
Baron, J. (1997). Confusion of relative and absolute risk in valuation. Journal of Risk and Uncertainty, 14, 301-309.
Baron, J. (1998). Judgment misguided: Intuition and error in public decision making. New York: Oxford University Press.
Baron, J. (2000). Thinking and deciding (3rd edition). New York: Cambridge University Press.
Breyer, S. (1993). Breaking the vicious circle: Toward effective risk regulation. Cambridge, MA: Harvard University Press.
Dudoit, S., & Ge, Y. (2003). Bioconductor R packages for multiple hypothesis testing: multtest.
Jenni, K. E., & Loewenstein, G. (1997). Explaining the"identifiable victim effect." Journal of Risk and Uncertainty, 14, 235-257.
Kuran, T., & Sunstein, C. R. (1999). Availability cascades and risk regulation. Stanford Law Review, 51, 683-768.
McDaniels, T. L. (1988). Comparing expressed and revealed preferences for risk reduction: Different hazards and question frames. Risk Analysis, 8, 593-604.
Ritov, I., & Baron, J. (1990). Reluctance to vaccinate: omission bias and ambiguity. Journal of Behavioral Decision Making, 3, 263-277.
Ritov, I., & Baron, J. (1999). Protected values and omission bias. Organizational Behavior and Human Decision Processes, 79, 79-94.
Slovic, P. (1998). Trust, emotion, sex, politics, and science: Surveying the risk-assessment battlefield. In M. H. Bazerman, D. M. Messck, A. E. Tenbrunsel, & K. A. Wade-Benzoni (Eds.) Environment, ethics and behavior: The psychology of environmental valuation and degradation, pp. 277-313. San Francisco: New Lexington Press.
Tengs, T. O., Adams, M. E., Pliskin, J. S., Safran, D. G., Siegel, J. E., Weinstein, M. E., & Graham, J. D. (1995). Five-hundred life-saving interventions and their cost-effectiveness. Risk Analysis, 15, 360-390.
Ubel, P. A. (2000). Pricing Life: Why It's Time for Health Care Rationing. Cambridge, MA: MIT Press.
Ubel, P. A., DeKay, M. L., Baron, J., & Asch, D. A. (1996). Cost effectiveness analysis in a setting of budget constraints: Is it equitable? New England Journal of Medicine, 334, 1174-1177.
Ubel, P. A., Baron, J., & Asch, D. A. (2001). Preference for equity as a framing effect. Medical Decision Making, 21, 180-189.
Viscusi, W. K. (2000). Corporate risk analysis: A reckless act? Stanford Law Review, 52, 547-597.
Westfall, P. H., & Young, S. S. (1993). Resampling-based multiple testing: Examples and methods for p-value adjustment. New York: John Wiley & Sons, 1993.


1This work was supported by a grant from the Russell Sage Foundation. Author's address: Department of Psychology, University of Pennsylvania, 3815 Walnut St., Philadelphia, PA 19104-6196
2Subjects were also more inclined to say that the company should install the device than to say that the agency should require it (.35 vs. .28, (t=2.82, p=.0058). There is no hypothesis about this difference.
3Trust in B was higher when the device is installed (the right two columns of the table averaging .80) than when it is not installed (left two columns .55, t=5.63, p=.0000), as if the thoroughness mattered mainly when the agent did what most subjects thought was the right thing, i.e., installing the device. But trust in B was positive even when the device was not installed (t94=9.94, p=0.0000).
4Company and agency did not differ.
5We also found a triple interaction among knowledge, betterness, and benefit [t=2.28, p = 0.0252]. The interaction between knowledge and betterness was greater when benefit was higher [50 lives]. We find this difficult to interpret.
6Although men showed a smaller positive effect of CBA on trust in Experiment 2 than did women, this result was not found in Experiment 1, and it may thus be a fluke that results from the small number of men in the sample, 29.
7Other data indicate that most subjects are indeed typical for the U.S. population in income and education (Babcock et al., 2003, whether they see themselves that way or not.

File translated from TEX by TTH, version 3.40.
On 23 Nov 2003, 14:44.