Final Program - Society for Risk Analysis

and 95th percentiles). Increasing the pasteurization temperature of milk may modestlyincrease the incidence of listeriosis caused by fluid milk consumption.P.89 Steinhardt JS, Scherer CW, Buckingham JL, Kermis AD, Klopp AL,Kubli KA, Ross E; jss399@cornell.eduCornell UniversityIN GOOGLE WE TRUST: PRESENTATION AND INFORMATIONSEEKING OF UNCERTAIN INFORMATION ABOUT THE 2011 JAPANNUCLEAR CRISISUsing the 2011 Japanese earthquake-tsunami as a focal point, this two part exploratorystudy examines 1) how individuals seek risk information and assess credibilityin sources online, and 2) how uncertain risk information is presented in newsstories and blogs on the internet. Through observation followed by qualitative interviewswith students at a large university the research explores the process of seekinginformation about the Fukushima 1 nuclear accidents and their impact on localfood safety as well as about the risks of building new domestic nuclear power plants.Participants were asked to evaluate these risks using any online sources available. Weconclude that students place a significant amount of trust in search engines as gatekeepersand believe that if a source comes up early in search results it is credible.Students believe that large corporations such as The New York Times and CNN havemore at stake if they report inaccurate information and place trust in their stories.Websites that students have not previously encountered and ones that they believeare poorly designed are also viewed as less credible. To better understand how uncertainrisk information is presented, and what sources information seekers could beaccessing, a sample of news stories from CNN, NPR, New York Times, and selectedblogs were analyzed. Stories were selected which discussed how nuclear contaminationin Japan was impacting food safety there and the United States. In general, weconclude that there is uncertainty in almost all of the content; however, many of thearticles make their claims with certainty. Very few articles actually contain scientificsources, however, almost all of the articles make scientific claims. Mainly these arethrough political sources. Other times, articles just make use of the words “officials,experts, and authorities.” Most articles represent two viewpoints (often: safe vs. unsafe),but stress one side or the other.W4-C.3 Steinzor R, Shudtz M; rsteinzor @ law.umaryland.eduUniversity of Maryland School of Law and the Center for Progressive ReformCORRECTIVE LENSES FOR IRISOver the last six years, the Center for Progressive Reform (CPR) has publisheda series of white papers about EPA’s Integrated Risk Information System. While supportiveof the program’s high quality of work, CPR’s papers are critical of the speedwith which new IRIS profiles are completed and old profiles are updated, the gapsin the database from the perspective of the public health advocacy community, andthe review processes employed by the agency. We have proposed several reforms tothe IRIS program that could eliminate data gaps and speed the assessment process.They include aligning the IRIS agenda with regulatory agendas in EPA’s air toxics anddrinking water programs, developing environmental-justice-based criteria for selectingchemicals to review, and streamlining all outside review of draft IRIS profilesinto a single stage. This presentation will cover CPR’s proposed reforms, as well asnew research about differences in the degree of participation in the IRIS processby potentially regulated parties versus the potential beneficiaries of health-protectiveregulation. CPR’s research generally, and our work on IRIS in particular, present across-disciplinary perspective on risk-based regulation.T4-I.3 Stiefel D, Tonn B; btonn@utk.eduUniversity of Tennessee, KnoxvilleASSESSMENT OF METHODS FOR ESTIMATING EXISTENTIALRISKS: PART IIThis presentation focuses on four ‘model’-based methods that one could use toestimate existential risks. The term ‘model’ is being used emphasize that the approachcontains a method for structuring how multiple factors interact with each other in acausal fashion that ultimately could lead to human extinction. The most establishedmethod to be discussed is known as Bayesian networks. Three other innovative methodsare also considered: influence modeling based on environmental scans; simpleelicitation using human extinction scenarios as anchors; and computationally intensivepossible worlds modeling. The four methods are also assessed about how well theapproach describes causal relationships between events that could lead to human extinction;level of elicitation efforts required of experts; ease of approach implementation;transparency of inputs into risk estimates; and acceptability of the approach.P.17 Streetman SS; steven.streetman@dataarchitecturesolution.comData Architecture Solutions, Inc., DHSENSURING CONSISTENCY IN RISK ANALYSIS EVENT TREES ANDCONSEQUENCESRisk is often evaluated by constructing event trees and estimating consequencesfor the scenarios built by the trees. This process is intended to construct a spanningset of scenarios that captures the risk for the scope of the assessment. In practice, it iseasy to overlook important sub-events that significantly impact the relative likelihoodand/or the relative risk of the scenarios. It is also common to estimate consequencesfor different types of scenarios using disparate models that may not be equivalentlyconservative and, thus, may skew the risk results, sometimes by multiple orders ofmagnitude - especially for rare and highly consequential events like terrorist attacks.The impact of inconsistency in event trees and consequence assessments tends togrow in severity and importance as the scope of the risk assessment broadens. In thistalk we will present notional examples of terrorism risk assessments where relative177