JOINT TRANSPORT RESEARCH CENTRE
Round Table, 11-12 December 2008, Paris

Discussion Paper No. 2009-6
March 2009

Security,
Risk Perception andCost-Benefit Analysis
SUMMARY AND CONCLUSIONS

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Security, Risk Perception and Cost-Benefit Analysis

TABLE OF CONTENTSFOREWORD .................................................................................................................. 4
1.

INTRODUCTION .................................................................................................. 5

2.

THE NATURE OF TERRORIST THREATS ......................................................... 6

3.

DETERMINING BEST-INFORMATION SUBJECTIVE PROBABILITIES ............. 7

4.

ECONOMIC ANALYSIS TO SUPPORT SECURITY POLICY DESIGN? ............. 95.

BROAD TYPES OF RESPONSES TO TERRORIST THREATS: SENSITIVITY,TARGET HARDENING, ADAPTATION .............................................................. 10

6.

RISK-BASED SECURITY MEASURES IN AVIATION? ..................................... 127.

SECURITY-MANAGEMENT IN MARITIME TRANSPORT ................................ 13

8.

CONCLUSION .................................................................................................... 14

REFERENCES ............................................................................................................. 16

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FOREWORD

This document summarizes discussions at the Round Table on Security, Risk Perception
and Cost-Benefit Analysis, held in Paris on 11-12 December 2008. The objective of theRound Table was to take stock of expertise on the assessment of risk and insecurity intransport and to consider how this expertise can be used to support project and policy
appraisal. The discussions were chaired by Andrew Evans (Imperial College London, UK)and based on four introductory reports, also available as JTRC Discussion Papers, which
can be downloaded from the links below:
Rapporteurs:
Dr. Khalid BICHOU (Imperial College London)
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200820.pdf
Prof. Peter GORDON/James. E. MOORE/Harry W. RICHARDSON ( University of Southern
California, USA)
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200822.pdf
Prof. André de PALMA (École Nationale Supérieure, Cachan, France)
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200821.pdf
Dr. Robert POOLE (Reason Foundation, USA)
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200823.pdf

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1. INTRODUCTION

Security concerns are high on the political agenda in many countries because of thewidespread perception that security is increasingly threatened by intentional malicious acts
including terrorist attacks. While terrorism has a long history and measures to maintain andimprove security are in place, major events – including but not limited to the 9/11 attacks –have triggered stronger action to improve security. In this context, much attention goes tomaintaining secure transport for two reasons. First, many transport facilities and vehicles areappealing targets for terrorist attacks because of the concentration of potential victims.
Second, transport can act as a conveyor for terrorist attacks, e.g. by moving weapons into
ports or by turning airplanes into weapons. In both cases, the difficulties in protecting themany potential targets while maintaining smooth transport operations strengthens the appealof transport targets.
The costs of potential damage from terrorism are substantial but so are the costs ofimproved security. Careful policy appraisal can help make good use of scarce resources.
This paper, which is drawn from debates during the round table on “Security, risk perception
and cost-benefit analysis”, held in Paris in December 2008, investigates how economic
analysis can contribute to the design of policies to maintain or enhance security in transport.
A standard economic approach to policy design is to evaluate the costs and benefits ofvarious policy options (“projects”). In order to make sense, a project’s benefits should exceed
its costs, and when choosing between alternative approaches, ranking alternatives according
to their net benefits helps inform policy decisions. However, cost-benefit analysis has
difficulty dealing with security issues, mainly because the benefits are uncertain or at leastextremely hard to quantify. As is discussed in Section 2, the basic problem is that it is hard todetermine the probability of terrorist attacks in an objective manner. Subjective probabilities
are available, but here the question is how they can be best determined. Section 3 provides
an overview of some methods to establish reasonable probability assessments for use inpolicy appraisal. Obviously, the design and implementation of security policies moves
forward whether a full-fledged cost-benefit analysis is available or not. Can economic
analysis be of use? Section 4 addresses this question. At least two types of useful input canbe thought of. First, economic analysis can help establish whether policies attain theirobjective at least possible cost. Second, careful economic modeling can chart the direct andindirect impacts of attack scenarios, and this information is of obvious relevance to thedefinition of policy priorities. Gordon et al. (2008) emphasize that, if the goal is to rank targets
in terms of impacts, there is a need for analyzing specific scenarios rather than defining
generic targets.
On the basis of the discussion of how economic analysis can help design responses,
Section 5 examines what broad response strategies are available, and how useful they areor could be. Sections 6 and 7 deal with aviation security and maritime security, mostly from acost-effectiveness point of view. This approach assesses if policies are well-designed in thesense of reaching their stated goal, however defined, at the lowest possible cost to society.
While judging the effectiveness of a policy is very difficult if it is unclear how it would affectthe probability of an attack, it is sometimes possible to judge if the mechanisms employed toSummary & Conclusions – Discussion Paper 2009-6 - © OECD/ITF, 20095

produce a given “security product” are the best available ones. Where such analysis has
been carried out, the results tend to be critical of current practice. Poole (2008), for example,
argues that aviation security as currently produced in the US, could be provided at lower costor – alternatively – better procedures could be provided with the same budget. For maritime
transport, there is considerable consensus that current initiatives are at best weakly effective.
In both sectors, policies appear to be inspired more by the need to show initiative thananything else. Section 8 concludes.

2. THE NATURE OF TERRORIST THREATS

The practice and analysis of security problems in transport is often inspired by work ontransport safety. However, safety and security are fundamentally different issues, because
safety is associated with risk while security is associated with uncertainty. In the case of risk,e.g. accident risk, the events are unintentional and their likelihood can be reasonably
estimated from empirical observations. But the probability with which intentional events thatcause security concerns will occur is much harder to quantify, for two reasons. First, terrorist
attacks are relatively infrequent. This is especially true of attacks that belong to the class of
extreme events, with low probabilities, major consequences, and possibly spillovers into
connected systems1. For such infrequent events, past events carry little information on futureprobabilities.
Second, attaching probabilities to intentional acts is particularly problematic because of
the possibility of strategic behavior: terrorists adapt their strategy to changes in the security
environment in which they operate. Since little is known about how they will respond(because the set of available strategies is very large), it is not clear how security policies orother relevant changes affect attack probabilities. In sum, terrorist attacks are notcharacterised by risk but by uncertainty, meaning that no credible objective probability can be
assigned to their occurrence.
Given this difficulty, the question is how reasonable probability assessments to support
security management can be obtained. Attempts to establish subjective probabilities use avariety of methods, including reliance on intelligence and expert opinion (see Section 3). The
challenge is to arrive at the best possible subjective probabilities, i.e. those that make thebest use of available information (“best-information subjective probabilities”; BSP). The BSP
are not common knowledge, because of the usual costs of disseminating information, butalso because best use of intelligence may require secrecy. For this reason, the BSP may
well differ from citizens’ subjective probabilities (CSP). There is evidence that, in general,
individuals’ perception of risk is characterized by risk aversion, misperception of probabilities,
and loss aversion. When objective probabilities are unknown, it is unclear whether citizens
tend to over- or underestimate the probability of a terrorist attack. However, if the commonly
observed characteristics of risk perception apply to the case of security, it is plausible that1

The average scale of terrorist attacks is small, but fundamentalist terrorism seeks mass casualties(Sandler and Enders, 2005), a phenomenon that arguably increases transport facilities’ appeal asa target.

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the probability of infrequent large scale attacks is overestimated compared to the BSP. One
question, to which we return below, is should policy be based on CSP or BSP.

3. DETERMINING BEST-INFORMATION SUBJECTIVE PROBABILITIESThere exist various sources of information on probabilities of terrorist attacks, including
intelligence services, insurance markets, expert opinion, and public opinion. The issue is how
to make best use of these sources for the design of security policy.
Intelligence services gather and interpret information on terrorist activity, so areparticularly well placed to form opinions on the likelihood and nature of future attacks. It is,however, less obvious that this information can be used in overall policy design, because of
secrecy restrictions, and because the information may be too short-term and microscopic tosupport strategic policy design. Secrecy requirements pose a principal-agent problem: theprincipal wants security, and needs to monitor agents’ operations to attain that objective, butmonitoring is difficult under the secrecy requirement. More broadly, strict secrecy policies
create a problem of accountability and potentially of legitimacy. Authorities could argue thatpolicies are justified by the information available to them but which cannot be made public. It
is therefore important to limit secrecy requirements to the absolute minimum and to establish
alternative sources of information, allowing democratic checks on whether policy choices
seem justified on the basis of a reasonable public assessment of security risks.
The insurance industry potentially is one alternative source of information. Private
underwriters have been attaching probabilities to a wide range of attack scenarios since the1970s, for the purpose of issuing terrorism risk coverage. The underwriters combine
historical records with intelligence and industry experience to assign probabilities. The
number of underwriters is small (though reportedly growing), and information on theirassessments of probabilities is commercially sensitive and not in the public domain.
Furthermore, evidence presented at the round table showed limited correlation between two
underwriters’ assessments of probabilities. Interpreting the probabilities is difficult without
information on the premiums charged. It appears that the market for this kind of risk is thin.
Information on ex post checks of the stated probabilities is not available either. These
shortcomings limit the extent to which this market is a source for determining BSP, a
shortcoming exacerbated by the potential problem that, because of a lack of transparency
and of competition, prices reflect willingness-to-pay, and not just expected costs. Increasedtransparency and a broader market are required before the industry’s probability
assessments can be turned into useful public knowledge.
Insurance companies also rely on catastrophe modelling. The approach here is to gather
and review intelligence, and to model it systematically, amongst other ways by eliciting
judgments on relative risks from experts. Subjective and objective information is combined
and made explicit in the form of a sequence of conditional probabilities. There are three large
companies that provide this kind of modelling. Insurance companies tend to use all threesources to decide on premiums. Public bodies, such as the Department of Homeland
Security, do not rely on these services for decision making, although the information is
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accessible to them in principle. One potential explanation is that public bodies have accessto information they think to be better. Another possibility is that assessments provided byprivate insurers usually are industry or transport mode-specific, so do not provide ideal
guidance for deciding on the general (public) provision of security.
In general, public and private provision of security and security insurance arecomplementary. Some security risks are too large or too strongly correlated to be covered by
the private sector (as diversification is difficult), so justifying public intervention, and some are
hard to monetize,. Public provision of security may induce positive spillovers by reducing theamount of coverage that needs to be provided privately. Oversimplifying somewhat, one
might argue that public policy should focus on improving overall security, while private
initiatives are better suited to managing risk at the level of specific targets. However, targetspecific risk management is fraught with problems. First, there is the possibility that better
management at one target just shifts risk to other targets, with little or no improvement ofoverall societal security (see Section 5). Second, individual operators’ measures to improvesecurity do not necessarily lead to lower insurance premiums, because insurers fear
“contamination” of more secure companies by less secure companies. The World Customs
Organisation Authorised Economic Operators program and the US C-TPAT program inmaritime transport can be mentioned as examples: operators in compliance with therequirements of these programs are not offered cheaper insurance. These problems again
highlight the need for coordinated public involvement in terrorism insurance.
Lastly, prediction markets could conceivably generate good information on subjective
probabilities. Prediction markets involve participants betting on outcomes. This offers theadvantage of including a real financial incentive. Such markets can reveal “the wisdom of thecrowds” (Surowiecki, 2004), and under certain conditions the aggregation of assessments
made by independently deciding individuals outperforms the assessments of the separate
individuals and possibly of individual experts. The main conditions are that there is diversityof opinion in the crowd (generated by different availability of information or different
interpretation of the same information) and that individuals independently make up theirmind. Experts may miss relevant issues that affect probability under scrutiny, especiallywhen working in strongly centralized environments.
Whether to base economic analysis of security-management (in as far as such analysis
is feasible, see Section 4.) on CSP or on BSP is a matter of judgment. One view, in line withwelfare economics, is that consumers’ evaluation of policy effects, based on CSP, is whatmatters. The other view is that in these matters government knows best (in technical terms,
security is a merit good), so that BSP is relevant. A practical approach is to evaluate
measures for both types of probability assessment, and present results for both cases topolicy-makers.
Summarizing, while there are several valuable sources of information for establishingsubjective probabilities, all have their shortcomings, and systematic approaches toaggregating and disseminating information are lacking. This compromises the generalpublic’s capacity to assess security threats and the responses to them. If as may well be thecase, threats are overestimated, this may imply acceptance of rather costly policies, even if
they are not very effective.

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4. ECONOMIC ANALYSIS TO SUPPORT SECURITY POLICY DESIGN?

Economic analysis aims to contribute to good policy-making through systematic
analysis of the costs and the effects of various policy approaches. Ideally, effects aremeasured in terms of benefits, so that costs and benefits can be compared and net benefits
calculated. Clearly, the presence of uncertainty poses difficulties for quantifying the benefitsof deterrence strategies, as it makes the impact of deterrence on probabilities extremely hardto determine2. Not only does uncertainty pose problems for determining the benefits of aprogram, it also compromises the capacity of analysis to determine how effective a programis in attaining its stated goals. That is, judging the effectiveness of security policy is hardwhen the counterfactual (i.e. what would happen in absence of the policy) cannot be
determined.
Against this background, an extreme view is that the risk management paradigm andeconomic analysis in general are not suitable for the support of security policy, as it is not
feasible to determine reasonable attack probabilities, the modelling of impacts is too sketchy
to be useful, and it is not possible to say how effective measures are in reducing threats.
Under these conditions, pursuing a quantitative assessment may lead to the adoption of
measures that infringe on civil liberties or are otherwise poorly legitimated, while theirbenefits are questionable3.
While the concern underlying this extreme view is widespread, few subscribe to the viewthat quantitative analysis is useless. If ways can be found to communicate the uncertainties
underlying quantitative assessments, then such analysis can help policy-makers decide on
their course of action. The tools used also provide a framework for thinking about the issues,i.e. the process is of value, not just the output, amongst other reasons because the tools are
consistent. Ultimately, of course, no analysis as such commits anyone to a particular way
forward.
Uncertainty imposes modesty on how much guidance economic analysis can provide,
but useful contributions are possible if the presence of uncertainty is explicitly accounted for.
Given the lack of precise information on probabilities, decision-making analysis ought to workwith ranges of probabilities under which some or other course of action is chosen. The
robustness of programs, i.e. their effectiveness under different assumptions on future events,
is also a useful indicator of their performance. Alternatively, if there is no information onprobabilities, one can determine what change in probabilities would be required to justify thecosts associated with some program. This at least forces decision-makers to be explicit on
why the program is expected to produce projected changes in threat levels.
2

Given the imperfect assessment tools, one might also say that the impact of security
measures on trade and other components of welfare is uncertain, so that deciding on
security policies involves trading off different uncertainties.

3

Note that it was argued in Section 3 that similar problems may arise in the absence ofeconomic analysis.

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A somewhat less ambitious approach is to carry out economic impact analysis, that is
attempt to trace the economic effects of a given attack scenario, where the scenario and theprobability with which it occurs are exogenous. Gordon et al. (2008) discuss the principles
underlying the modeling of the economic impacts of attack scenarios, and provide someexamples. They emphasize that, if the goal is to rank targets in terms of impacts, there is aneed for analyzing specific scenarios rather than defining generic targets: analysis needs tofocus on a specific port, airport, or other potential target, not on an abstract target.
Furthermore, the assessment needs to be spatially disaggregated, looking at businessinterruption effects at sub-national and sub-metropolitan levels, as the main policy interest is
at those levels. The tools discussed in Gordon et al. (2008) focus on short run impacts anddo not allow for price adjustments. Economic impact analysis is not cost-benefit analysis: ithelps in determining priority rankings for target hardening (an important component of current
security policies, see next section), but does not offer a framework for comparing costs andbenefits.
While most experts subscribe to the view that models are useful in supporting policy,
some warn against the use of overly complex and data-rich tools. Given the uncertainties
associated with security, simple models are likely to be more structurally stable than complex
tools, implying that they are better suited for a forward-looking analysis. The lack of precise
answers coming from such simple but stable models reflects the uncertainties underlying theanalysis. Any precise statement on what to do, whatever its source, is suspect given the
structural uncertainty that characterizes security problems. Given the nature of terrorist
threats, there is no way to define how to respond optimally under all circumstances.
Responses will need to adapt on a continuing basis. Presumably, then, the role of economic
analysis is to make current security policy less bad, and to avoid the biggest mistakes. From
this point of view, the next sections discuss broad policy responses as well as aviation andmaritime security measures.

5. BROAD TYPES OF RESPONSES TO TERRORIST THREATS:SENSITIVITY, TARGET HARDENING, ADAPTATION

Terrorism can be seen as a violent response to prevailing patterns of economic,
social and cultural interactions (institutions), by groups that see themselves – for good or forbad reasons – as disadvantaged by those patterns. While one dislikes the type of response,
it is worth asking what can be done to change the perception of disenfranchisement.
De Palma (2008) calls for such “sensitivity” in our attempts to manage the future, andsuggests that institutional change is a key component of a credible strategy for managing
terrorist threats in the long run. In a similar vein, Sandler et al. (2008) argue that improved
international cooperation and reorientation of international policy-making produces net
benefits4. Clearly, standard economic tools, such as cost-benefit analysis, are of very limited
4

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ASPI, 2008, criticizes Sandler et al. (2008) for considering too limited a set of policy options,
ignoring psychological costs of terrorism and potential co-benefits of counter-terrorism spending,and notes there is little explicit evidence for the connection between US foreign policy andtransnational terrorism.
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use when thinking about institutional change. They are too imprecise to put reasonable
numbers on the costs and benefits of such broad strategies, and are indeed not designed forthe purpose. Democratic societies use different mechanisms to arrive at decisions on suchbroad policy directions.
Independent of the extent to which institutional change is pursued, societies will respondto prevailing security threats in some way or other. Target-hardening is a response that aims
to make it harder for terrorists to strike against selected targets. A fundamental problem withthis strategy concerns the selection or prioritization of targets, given the multitude of potential
targets and terrorists’ flexibility in responding to any set of measures. Target-hardening
ideally should be flexible and dynamic rather than attempt to build walls around selected
targets, but current practice deviates strongly from this ideal.
Even under ideal conditions, many think that target-hardening is fundamentally not very
effective and therefore a losing strategy, except possibly in terms of political windowdressing. Sandler et al. (2008) find the net benefits of most target-hardening measures to be
negative, with costs exceeding benefits by a factor of 10 or so. The main reason for thislimited effectiveness is that terrorists can easily adapt to policies given the multitude ofpotential targets. The extreme position is that target-hardening shifts probabilities amongtargets but does not reduce the aggregate probability of an attack at all. Not all experts
subscribe to this view, however, on the argument that terrorist organizations do perform arisk-management calculus, so can be influenced by deterrence strategies. Intriligator (2008)
supports the conclusion that target hardening has not produced net benefits in as far as it
pertains to the security risks posed by past attacks but goes on to argue that the possibility ofan attack involving weapons of mass destruction, e.g. nuclear weapons, should not beignored. Given the potentially very high costs of such an attack, improved security and target
hardening may be worthwhile, even if analysis of past events shows that economic impacts
were limited and target-hardening not very effective.
To the extent target-hardening is adopted as a strategy, care should be taken to make ita flexible strategy. One way to increase flexibility in security policy is for regulation to focus
on outcomes, not on the process. This contrasts with much regulatory practice, which tends
to be strongly or entirely prescriptive. For example, in aviation security, Transport Canada
decides on the measures to be taken and the implementing agency CATSA, which has the
security-expertise, has no flexibility to modify or augment the measures it employs. This
separation of responsibilities is important for the governance of security policy but could
perhaps be made more flexible by a shift to outcome oriented monitoring of performance.
The difficulty with outcome-oriented regulation, however, is that the ultimate product(security) is elusive, so that intermediate goals need to be determined (e.g. percentage ofpassengers screened) which again risks introducing rigidities in operating practice. The useof “red teams” (personnel that simulate terrorist behaviour to test the workings of defence
mechanisms) can be used to measure effectiveness and could perhaps be relied on as themain outcome-oriented control.
Given that reducing incentives to stage terrorist attacks takes a long time and is not
likely to be entirely successful, and given that target hardening is far from perfect even in its
optimal form, it follows that terrorist threats and the occurrence of terrorist attacks areinevitably associated with current institutions. More prosaically, terrorism is a cost of doing
business. A useful third component of a comprehensive response strategy then is to findways to reduce the impacts of terrorist attacks through adaptation (impact reduction, disasterrecovery, responses to emergencies, etc.). This component was not discussed extensively at
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the round table, but it is obviously important, and useful insights on system resilience areavailable from literature on natural disasters (see Rose, 2007, for a conceptual discussion).
In short, responses to terrorist threats involve three types of measure: reduce the
incentives to pursue terrorist strategies, protect targets and reduce the impacts in caseattacks take place. The following two sections discuss aspects of target-hardening in thecontext of aviation and maritime transport.

6. RISK-BASED SECURITY MEASURES IN AVIATION?

Poole (2008) argues that a cost-effective air passenger screening policy must be riskbased, and that current policy is only risk-based in name. He proposes a three-tiered systemthat focuses on detecting dangerous passengers rather than dangerous objects, as iscurrently done. Up to 50% of travellers would be able to volunteer for registered traveller
programs that would involve voluntarily submitting to security profiling. Many frequent
travellers would sign up to such systems in order to reduce queuing time at airports.
Screening for low-risk passengers would be limited, although random checks would be
retained to avoid easy gaming of the system. With this approach, more resources become
available for dealing with higher risk categories of passengers, and especially the 1% or lesscategorised as high-risk travellers. This would permit attaining the same level of security atlower cost, or better security without increasing expenditure.
Distinguishing passengers on the basis of the risk they pose involves profiling. The
profiling is intelligence based, so is less prone to perceptions of discrimination than statisticalprofiling. Good profiling obviously requires good intelligence (how to decide which travellers
do not pose a terrorist risk?), and agencies that make efficient use of the available
information (whereas the US Transport Security Agency currently does not use available FBI
materials to perform criminal background checks).
While few experts deny the economic sense of the proposal, some difficulties remain.
First, political acceptance of the system may be low, for example because of equity
concerns. Second, switching to a risk-based screening system requires changing
regulations, a lengthy process that could take up to 10 years according to some.
Furthermore, it is not clear that a passenger-oriented approach instead of an object-oriented
approach is sufficiently legitimate to be implemented, even if it is more efficient than an
object-based approach.
Current aviation security procedures mostly focus on reducing the risk of terrorists
boarding planes. It is conceivable that placing separate security checks nearer gates, insteadof using a single point of control for all passengers, serves this goal better. However, such asystem would reduce security within the airport, which itself may be a target for a terrorist
attack.
It was noted that aviation security policies mainly seem to respond to a need “to dosomething”. Some recent changes in security measures have been labelled “security
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theatre”, because the measures are quite visible but their effectiveness is questionable. Suchan approach seems more in line with policy-making on the basis of CSP, in the sense of
attempting to reduce public concerns about security, rather than effectively reducing theprobability of attacks. To the extent that reduced concerns improve welfare, such policies
entail benefits, but the desirability of such a policy approach can be questioned (seeSection 3).

7. SECURITY-MANAGEMENT IN MARITIME TRANSPORT

The maritime transport sector is complex, not very transparent, and by its naturestrongly international. For these reasons it is difficult to arrive at a systematic andcoordinated approach to the regulation of security (as well as of other issues). An effective
framework for security management should be multi-layered, as it needs to address the
security of cargo traffic, of vehicles and facilities, and of supply chains. Such a framework
does not exist, however: the term “supply chain spaghetti” is sometimes used to refer to themultitude of regulatory initiatives that overlap and possibly contradict each other.
US initiatives on maritime security drive much of the debate on the costs and benefits ofmaritime security policy. The Secure Freight Initiative receives most attention, with its goal of
100% scanning of US-borne containers by 2012. It is sometimes argued that many emerging
security initiatives at ports outside the USA are driven by the fear that doing nothing will
make it hard or impossible to export to the USA, not by security concerns as such. This
incentive may compromise the effectiveness of the measures that are taken.
At present, 0.1 to 1% of all containers imported into Europe are inspected. For
containers exported to the US, the inspection rate is about 2%. 100% inspection is not thebest target for a cost-effective security policy. It is not optimal5 and is probably not feasible.
Current inspection rates suggest that supply chain security is more a topic of debate than anobservable practice. The approach of scanning containers in itself is subject to criticism,
because detection rates are low. Furthermore, bulk and tramp transport is not controlled,
while it arguably is as susceptible to carrying bombs and other hazardous material as
container traffic.
Bichou (2008) argues that the maritime transport industry as a whole might benefit from
improved security management through improvements in operating efficiency triggered by it(implying that some actors in the industry currently are not minimizing costs). Such benefits
may emerge, but they are not proven. The hypothesis that regulatory compliance canincrease productivity lacks empirical support in most cases where it has been studied. In
addition, it is clear that not all parties will gain. Smaller ports and operators in particular are
likely to suffer from stricter security requirements, given that regulatory compliance involves
substantial fixed costs. This raises concerns regarding the impact of security measures oncompetition.
5

It is not clear what level of screening would be best to equilibrate benefits from deterrence andsecurity costs.

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With respect to maritime transport, there is a widespread sentiment that the security
measures that are implemented or are being debated achieve very little or nothing, except
possibly that they raise awareness of security concerns among seafarers. There is also little
confidence that measures are progressively being improved (“closing more doors”). There isa tendency for security measures to be driven by access to funding or by the need tomaintain access to some markets, rather than by a real desire to improve security in an
effective manner.

8. CONCLUSION

The objective of the round table was to take stock of the expertise on the assessmentof risk and insecurity in transport, to discuss how the expertise can support project and policy
appraisal, and which gaps in knowledge remain. First, it is important to note that terrorist
threat issues are fundamentally different from safety issues. Security is characterized byuncertainty, meaning that no objective probabilities can be determined for the occurrence of
attacks. Uncertainty makes economic analysis difficult. The tools developed for costing risks,e.g. on the basis of historical accident records, cannot be applied to events that are
uncertain. Moreover terrorists adjust their strategies according to the security measurestaken, something that does not happen in relation to accidents. This limits the extent to which
experience with safety policies can help make better security policy.
Subjective probabilities on terrorist attacks can be gleaned from intelligence, theinsurance industry, and prediction markets. None of these sources is without shortcomings,
but all are useful and can contribute to a systematic and transparent approach to establishing
the probabilities underlying security policy design. Such an approach is currently lacking in
national security policy development, and given a likely tendency for individuals tooverestimate terrorism risk, this situation is conducive to high and poorly targeted spending
on security. Many security measures in aviation and in maritime transport are broadly
assessed not to be effective, so they do not provide value for money.
Economic analysis could help improve the effectiveness of security policies. For
example, economic impact analysis is useful for determining the likely economic costs fromvarious attack scenarios. More broadly, systematic economic analysis provides insight in
how deterrence strategies hold up under alternative assumptions on how likely attacks are tooccur. Economics also clarifies how stated security goals can be attained at the lowest
possible cost. For example, switching from process-oriented to output-oriented regulation
likely improves the effectiveness of passenger screening in aviation. Risk-profiling in aviation
screening, in order to concentrate resources where they are most needed whilst maintaining
random checks on pre-screened passengers, is probably the key measure for achieving
better levels of security from the resources spent. The use of profiling has been handicappedby concerns that it can be used to discriminate between citizens on inappropriate grounds
and could raise privacy issues. However, an opt-in approach can be used where passengers
wishing to benefit from faster passage chose voluntary profiling.

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Summary & Conclusions – Discussion Paper 2009-6 -© OECD/ITF, 2009

In sum, the economic analysis reviewed at the round table is critical of current security
policies, which are seen to be largely ineffective in improving security, and too expensive interms of attaining intermediate goals (such as screening rates) that are easy to measure but
give little indication of the true degree to which security is improved. Security policies are, on
the whole, wasteful. For this criticism to be taken seriously, clear alternatives need to be put
forward. The alternatives put forward, such as profiling, sometimes lack political support.
Rather than abandoning such improvements it would seem appropriate to devote greater
efforts towards developing safeguards against misuse and informing politicians and the
public on the safeguards and the merits of the improved measures available. Otherwise
policy will continue to be wasteful, a price that many policy-makers appear willing to impose
on society in return for creating the perception that “something is being done”. , Greatertransparency on the expected costs of terrorist threats might also help reduce waste bymoderating the demand for action. Most importantly better levels of security could beachieved with the resources currently devoted to it.

Summary & Conclusions – Discussion Paper 2009-6 - © OECD/ITF, 200915

REFERENCESASPI (Australian Strategic Policy Institute), 2008, Risky Business – Measuring the costs andbenefitsofcounter-terrorism
spending,
SpecialReport,Issue
18.
http://www.aspi.org.au/publications/publication_details.aspx?ContentID=190&pubtype=10
Bichou, Khalid, 2008, Maritime security and risk-based models: review and critical analysis,
JTRC Discussion paper 2008-20.
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200820.pdf
de Palma, André, 2008, Rationalité, aversion au risque et enjeu sociétal majeur, JTRC
Discussion paper 2008-21,
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200821.pdf
Gordon, Peter, James E. Moore II, and Harry Richardson, 2008, Economic impact analysis ofterrorism events: recent methodological advances and findings, JTRC Discussion paper
2008-22,.
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200822.pdf
Intriligator, Michael D., 2008, On “Transnational Terrorism” - Perspective Paper on the Todd
Sandler, Daniel G. Arce, and Walter Enders Paper for the 2008 Copenhagen
Consensus. (http://www.copenhagenconsensus.com/Default.aspx?ID=1152 )Poole, Robert W., 2008, Toward risk-based aviation security, JTRC Discussion Paper 2008-23.
http://www.internationaltransportforum.org/jtrc/DiscussionPapers/DP200823.pdf
Rose, Adam, 2007, Economic resilience to natural and man-made disasters: multidisciplinary
origins and contextual dimensions, Environmental Hazards, 7, 4, 383-398.
Sandler, Todd, Daniel G. Arce and Walter Enders (2008) Terrorism – Copenhagen
Consensus
2008
Challenge
Paper,
Copenhagen
Consensus
Center(http://www.copenhagenconsensus.com/Default.aspx?ID=1152 ).
Surowiecki, James, 2004. The Wisdom of Crowds: Why the Many Are Smarter Than the Few
and How Collective Wisdom Shapes Business, Economies, Societies and Nations,Random House.

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Summary & Conclusions – Discussion Paper 2009-6 -© OECD/ITF, 2009

ROUND TABLE 145: SECURITY, RISK PERCEPTION AND COST-BENEFIT ANALYSIS
Paris, 11-12 December 2008
LIST OF PARTICIPANTS

Chair:

Participants:

Prof. Andrew EVANS
Imperial College, University of London
LONDON
United Kingdom

Dr. Torkel BJORNSKAU
Institute of Transport Economics
OSLO
NorwayRapporteurs:
Dr. Khalid BICHOU
Imperial College, University of London
LONDON
United Kingdom

Prof. Peter GORDON/James E. MOORE II/
Harry RICHARDSON
University of Southern California
LOS ANGELES
USA

Prof. André DE PALMA
Ecole Normale Supérieure de Cachan
CACHANFranceDr. Robert POOLE
Reason Foundation
LOS ANGELES
USA

Mr. Andrew COOK
Department for Transport
LONDON
United Kingdom
Dr. Andrew GRAINGER
Trade Facilitation Consulting Limited
KINGSTON UPON THAMES
United Kingdom
Dr. Juha HINTSA
Cross-Border Research Association
LAUSANNE
Switzerland
Dr. Brian JACKSONRAND Corporation
ARLINGTONUSA
Mr. Carl KOOPMANS
Ministry of Transport, Public Works andWater Management
THE HAGUE
The Netherlands
Prof. Dr.-Ing. Juergen KRIEGER
Federal Highway Research Institute
BERGISCH GLADBACH
Germany
Dr. David LEVINSON
University of Minnesota
MINNEAPOLIS
USA

Summary & Conclusions – Discussion Paper 2009-6 - © OECD/ITF, 200917

Mr. Alex MACFARLANE
Department for Transport
LONDON
United Kingdom

Monsieur Rene VAN BEVER
Service public fédéral Mobilité et Transports
BRUSSELS
Belgium

Dr. Susan MARTONOSIHarvey Mudd College
Claremont, CA
USA

Professor David WIDDOWSON
University of Canberra
CANBERRA
Australia

Prof. Daniel MIRZA
Université François-Rabelais
TOURS
FranceDr. Andrew MORRALRAND Corporation
ARLINGTONUSA
Mr. Serge PAHAUT
Université Libre de Bruxelles
BRUSSELS
Belgium
Prof. Barry E. PRENTICE
University of Manitoba
Winnipeg
CanadaDr. Mark B. SALTER
University of Ottawa
OTTAWA
CanadaDr. Risto TALAS
Cass Business School
GB-LONDON
United Kingdom
Dr. Nicolas TREICH
Toulouse School of Economics (TSE)TOULOUSE
France18

Summary & Conclusions – Discussion Paper 2009-6 -© OECD/ITF, 2009