MCLEAN, Va., Jan. 27, 2015 /PRNewswire-USNewswire/ -- The
public is more likely to trust and comply with bad weather
warnings--such as for winter snowstorms and icy roads--if
authorities give their warnings as a probability estimate,
according to risk researchers. The researchers were seeking to
understand why the public is likely to respond to authorities'
guidance amid "false alarms." As severe storm and other disaster
warnings become more frequent under climate change (which
scientists predict will increase the number and severity of
hurricanes, tornadoes and floods), new research in this field could
become critical for reducing weather-related injury and death.
In their new paper, "The Cry Wolf Effect and Weather-Related
Decision Making," Jared LeClerc and
Susan Joslyn of the University of Washington examine the impact of
false alarms on the participants' willingness to take precautions
when authorities issue warnings and urge action. The authors note
that excellent U.S. National Weather Service forecasts with
substantial lead times have not prevented "massive loss of life"
because the public too often has failed to take warnings seriously.
Most researchers now recognize that psychological factors are a big
part of the problem of public noncompliance with warnings. The
LeClerc and Joslyn paper recently appeared in the online version of
Risk Analysis, a publication of the Society for Risk Analysis.
The researchers point out that complicated factors govern
people's reluctance to heed advice. When urged to evacuate their
homes, for example, residents have cited concerns about travel
expenses, dangers on the highway, inconvenience, and property
losses from looting. However, "lack of trust in the warning" also
may limit the public's willingness to comply with orders. Although
the impact of false alarms--or the "cry wolf" effect--has been
widely discussed, evidence remains unclear about how people's
experience of false alarms affects their trust in weather
warnings.
To understand better the psychology of this increasingly
critical topic of the public's trust in and compliance with
warnings, LeClerc and Joslyn designed a controlled laboratory
experiment in which they could "systematically manipulate the rate
and degree of prior exposure to false alarms" to observe the
effects on participants' trust in the warnings and decisions about
taking recommended actions. A key question was whether increasing
the number of false alarms would decrease the willingness of
experiment participants to take precautionary actions.
The experiment involved 354 University of
Washington psychology students who participated for course
credit and an opportunity to earn prize money. Participants played
the role of a road maintenance company under contract to apply salt
brine to roads in a U.S. town to prevent icing. Applying salt brine
cost $1,000 a day, but failure to
salt when freezing temperatures occurred resulted in a $5,000 penalty for the company. The experiment
used historical forecast data from the cities of Spokane and Yakima in Washington
State on the ranges of temperature, probabilities of
freezing and forecast error. Participants were given a virtual
monthly budget of $35,000 and were
instructed to maximize profits by minimizing salting expenses and
avoiding penalties. Salting had to occur before freezing
temperatures were reached. Some participants received the advice of
a decision support aid that recommended for or against salting
based on whether the probability of freezing was above or below a
certain threshold. Participants registered their trust in nighttime
low temperature forecasts on a six-point scale, ranging from "not
at all" to "completely."
The results provided "the first evidence of which we are aware
for a significant cry wolf effect in weather-related decision
making using a controlled experimental approach," even if the
effect size was moderate, the authors conclude. Overall, when nine
more false alarms were issued (38 out of 56 total salting
recommendations, or 68 percent) experiment participants were "less
likely to follow advice." The nine additional false alarms were
compared with normative false alarm levels (29 out of 45 total
salting recommendations, or 64 percent). The participants also
trusted warnings less and "made economically inferior decisions"
that reduced their virtual earnings, according to the
researchers.
"The bottom line here is that false alarms may indeed be a
subtle contributing factor to noncompliance with weather warnings,"
the authors state. Most significantly, according to the authors,
adding a probability of freezing to the forecast "led to greater
compliance with the advice and greater increase in decision quality
than did lowering the false alarm level" and the implications of
that finding are important for warning situations.
Risk Analysis: An International Journal is published by the
nonprofit Society for Risk Analysis (SRA). SRA is a
multidisciplinary, interdisciplinary, scholarly, international
society that provides an open forum for all those who are
interested in risk analysis. Risk analysis is broadly defined to
include risk assessment, risk characterization, risk communication,
risk management, and policy relating to risk, in the context of
risks of concern to individuals, to public and private sector
organizations, and to society at a local, regional, national, or
global level. www.sra.org
Contact: David Clarke,
301-670-4990, davidpaulclarke@gmail.com to arrange an interview
with the author(s). Note to editors: The complete study is
available upon request from David
Clarke or here:
http://onlinelibrary.wiley.com/doi/10.1111/risa.12336/full
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SOURCE Society for Risk Analysis