Amplification occurs at two stages: in the transfer of information about the risk, and in the response
mechanisms of society. Signals about risk are processed by individual and social amplification
stations, including the scientist who communicates the risk assessment, the news media, cultural
groups, interpersonal networks, and others.
KEY WORDS: Risk; risk perception; social amplification; technological controversies; public
participation.
- The technical concept of risk focuses narrowly on the probability of events and the
magnitude of specific consequences. Risk is usually defined by multiplication of the two
terms, assuming that society should be indifferent toward a low-consequence/high-
probability risk and a high-consequence/lowprobability risk with identical expected values.
Studies of risk perception have revealed clearly, however, that most persons have a much
more comprehensive conception of risk. Clearly, other aspects of the risk such as
voluntariness, personal ability to influence the risk, familiarity with the hazard, and the
catastrophic potential shape public response.(’*2) As a result, whereas the technical
assessment of risk is essential to decisions about competing designs or materials, it often fails
to inform societal choices regarding te~hnology.‘~)
- Cognitive psychologists and decision researchers have investigated the underlying patterns of
individual perception of risk and identified a series of heuristics and biases that govern risk
per~eption.(~*~) Whereas some of these patterns of perception contrast with the results of
formal reasoning, others involve legitimate concern about risk characteristics that are
omitted, neglected, or underestimated by the technical concept of risk. In addition, equity
issues, the circumstances surrounding the process of generating risk, and the timeliness of
management response are considerations, important to people, that are insufficiently
addressed by formal probabilistic risk
- Risk is a bellwether in social decisions about technologies. Since the resolution of social
conflict requires the use of factual evidence for assessing the validity and fairness of rival
claims, the quantity and quality of risk are major points of contention among participating
social groups. As risk analysis incorporates a variety of methods to identify and evaluate risks,
various groups present competing evidence based upon their own perceptions and social
agenda. The scientific aura surrounding risk analysis promotes the allocation of substantial
effort to convincing official decision makers, and the public, that the risk assessment
performed by one group is superior in quality and scientific validity to that of others.
Controversy and debate exacerbate divergences between expert and public assessment and
often erode confidence in the risk decision proces~
In short, the technical concept of risk is too narrow and ambiguous to serve as the crucial yardstick
for policy making.
Public perceptions, however, are the product of intuitive biases and economic interests and reflect
cultural values more generally.
The main thesis of this article is that risk events interact with psychological, social, and cultural
processes in ways that can heighten or attenuate public perceptions of risk and related risk behavior.
Behavioral patterns, in turn, generate secondary social or economic consequences but may act also
to increase or decrease the physical risk itself. Secondary effects trigger demands for additional
institutional responses and protective actions, or, conversely (in the case of risk attenuation), impede
needed protective actions. The social structures and processes of risk experience, the resulting
repercussions on individual and group perceptions, and the effects of these responses on
, community, society, and economy compose a general phenomenon that we term the social
amplification of risk.
Social amplification provides a corrective mechanism by which society acts to bring the technical
assessment of risk more in line with a fuller determination of risk.
At the other end of the spectrum, the relatively low levels of interest by the public in the risks
presented by such well-documented and significant hazards as indoor radon, smoking, driving
without seat belts, or hghly carcinogenic aflatoxins in peanut butter serve as examples of the social
attenuation of risk.
Whereas attenuation of risk is indispensible in that it allows individuals to cope with the multitude of
risks and risk events encountered daily, it also may lead to potentially serious adverse consequences
from underestimation and underresponse. Thus both social amplification and attenuation, through
serious disjunctures between expert and public assessments of risk and varying responses among
different publics, confound conventional risk analysis.
In communications theory, amplification denotes the process of intensifying or attenuating signals
during the transmission of information from an information source, to intermediate transmitters, and
finally to a receiver.
Each message may contain factual, inferential, value-related, and symbolic meanings.‘”)
- The factual information refers to the content of the message (eg, the emission of an air
pollutant is X mg per day) as well as the source of the message (e.g., EPA conducted the
measurement).
- The inferential message refers to the conclusions that can be drawn from the presented
evidence (e.g., the emission poses a serious health threat).
- Then those conclusions may undergo evaluation according to specific criteria (e.g., the
emission exceeds the allowable level). In addition, cultural symbols may be attached that
evoke specific images (e.g., “big business,” “ the military-industrial complex,” “high
technology,” etc.) that carry strong value implications.
Communication studies have demonstrated that the symbols present in messages are key factors in
triggering the attention of potential receivers and in shaping their decoding processes Depending on
the source, the content of the message may well command public attention. Some sources are seen
as credible, others are not.
The interaction between risk events and social processes makes clear that, as used in this framework,
risk has meaning only to the extent that it treats how people think about the world and its
relationships. Thus there is no such thing as “true” (absolute) and “distorted” (socially determined)
risk. Rather the information system and characteristics of public response that compose social
amplification are essential elements in determining the nature and magnitude of risk.
Like a stereo receiver, the information system may amplify risk events in two ways:
- By intensifying or weakening signals that are part of the information that individuals and
social groups receive about the risk;
- By filtering the multitude of signals with respect to the attributes of the risk and their
importance.