Uncertainty and decision making: Volcanic crisis scenarios

Abstract

a b s t r a c tThe impact of uncertainty on Disaster Risk Reduction decision-making has become a pressing issue for debate over recent years. How do key officials interpret and accommodate uncertainty in science advice, forecasts and warnings into their decision making? Volcanic eruptions present a particularly uncertain hazard environment, and to accommodate this scientists utilize probabilistic techniques to inform decision-making. However, the interpretation of probabilities is influenced by their framing. We investigate how verbal or numerical probabilities affect decisions to evacuate a hypothetical town, and reasons given for that decision, based upon a volcanic eruption forecast. We find fewer evacuations for verbal terms than for equivalent numerical terms, and that the former is viewed as more ambiguous. This difference is greater for scientists, which we suggest is due to their greater familiarity with numerical probabilities and a belief that they are more certain. We also find that many participants have a poor understanding of the relationship between probability and time window stated, resulting in an incorrect assessment of overall likelihood and more evacuations for the lower likelihood version of two scenarios. Further, we find that career sector (scientist or non-scientist) influences evacuation decisions, with scientists tending to reduce the uncertainty by focusing on the quality and volume of information provided, while non-scientists tended to either acknowledge or suppress the uncertainty, focusing on actions to take. These findings demonstrate the importance of identifying communication strategies that mitigate different perceptions of forecasts, to both enhance end-user decision making and to prevent premature, delayed, or unnecessary actions.

Enhancing scientific response in a crisis: evidence-based approaches from emergency management in New Zealand

“…These exercises not only provide opportunities to practice communications and plans and enhance these team mental models, but also for scientific agencies to rehearse strategies to convey uncertainty and how it could be included Doyle et al 2014a& Doyle et al 2014b, and for other agencies to be able to develop associated contingent planning. In addition, exercise and scenario planning can also help to answer if we are doing the right science for the response as well as for the advancement of science.…”

Decision-Making: Preventing Miscommunication and Creating Shared Meaning Between Stakeholders

“…The first, known as either Type 1 or the affective processing system, involves rapid, unconscious, action-oriented processing, and results in people interpreting risk as an emotional state or feeling (e.g., fear, dread, anxiety; Epstein 1994; Loewenstein et al 2001;Slovic et al 2004;Doyle et al 2014b), and can thus reduce or increase risk perceptions. These are assumed to be the default response "unless intervened by distinctive higher order" Type 2 processes (Evans and Stanovich 2013a), or analytical processing systems (Epstein 1994), which heavily load working memory, and utilise hypothetical thinking, more deliberate computational cognitive processes (and thus longer decision times).…”

“…On the one hand, the communication of uncertainty has been suggested to enhance credibility and trustworthiness. On the other, however, studies have suggested that it can decrease people's trust and the credibility of the provider, as it can allow people to justify inaction or their own agenda, or to perceive the risk as being higher or lower than it is depending on their personal attitudes (Johnson andSlovic 1995, 1998;Smithson 1999;Miles and Frewer 2003;Johnson 2003;Wiedemann et al 2008;Doyle et al 2014b). The role of ethics in whether or not to communicate uncertainty has also become a focus of recent discussion across disciplines, including whether communicating this uncertainty actually enhances or diminishes the autonomy of the receiver of the message, and whether it produces an overall benefit or can actually cause harm (Han 2013;Austin et al 2015;Grasso and Markowitz 2015).…”

“…Trust influences organizational intention to collaborate and share information between stakeholders (Mohr and Spekman 1994;Kapucu 2006 Fig. 3 The factors that affect the interpretation of forecasts, and the influences on resultant decision making (Doyle et al 2014b, after the graphical abstract of Doyle et al 2014a) Decision-Making: Preventing Miscommunication …the eruptions of Soufriere Hills Volcano, Montserrat, WI, where Haynes et al (2007) identified that this trust was influenced by a number of factors including: competence; integrity; value similarity; openness; and conflicting messages of safety and danger. Trust in the scientists was based upon high perceived reliability, competence, openness and integrity; while trust in government authorities was based upon high perceived levels of competence, reliability, and fairness.…”

Legal framework and scientific responsibilities during volcanic crises: the case of the El Hierro eruption (2011–2014)

“…The non-deterministic behavior of the observed phenomena, as in the case of weather or volcanic eruptions (Altamura et al 2011;Doyle et al 2014b), limits our capacity for forecasting them, even in the short-term, thus making the management of such natural hazards more difficult. Therefore, when the hazard they face is threatening a highly-populated area, scientists, Civil Defense personnel and politicians must make decisions, in real time and under uncertainty, in a context of great pressure (Marzocchi et al 2012).…”