Lost in translation? Interpretations of the probability phrases used by the Intergovernmental Panel on Climate Change in China and the UK

Tackling climate change is a global challenge and the Intergovernmental Panel on Climate Change (IPCC) is the organisation charged with communicating the risks, dangers and mechanisms underlying climate change to both policy makers and the general public. The IPCC has traditionally used words (e.g., ‘likely’) in place of numbers (‘70 % chance’) to communicate risk and uncertainty information. The IPCC assessment reports have been published in six languages, but the consistency of the interpretation of these words cross-culturally has yet to be investigated. In two studies, we find considerable variation in the interpretation of the IPCC’s probability expressions between the Chinese and British public. Whilst British interpretations differ somewhat from the IPCC’s prescriptions, Chinese interpretations differ to a much greater degree and show more variation. These results add weight to continuing calls for the IPCC to make greater use of numbers in its forecasts.

[1]  Silja Renooij,et al.  Evaluation of a verbal-numerical probability scale , 2003, Int. J. Approx. Reason..

[2]  Elke U. Weber,et al.  Contextual Effects in the Interpretations of Probability Words: Perceived Base Rate and Severity of Events , 1990 .

[3]  T. Doupnik,et al.  The Impact of Culture on the Interpretation of “In Context” Verbal Probability Expressions , 2004 .

[4]  G. Box.  Some Theorems on Quadratic Forms Applied in the Study of Analysis of Variance Problems, II. Effects of Inequality of Variance and of Correlation Between Errors in the Two-Way Classification , 1954 .

[5]  Adam J. L. Harris,et al.  Communicating environmental risks: Clarifying the severity effect in interpretations of verbal probability expressions. , 2011, Journal of experimental psychology. Learning, memory, and cognition.

[6]  David V. Budescu,et al.  Improving Communication of Uncertainty in the Reports of the Intergovernmental Panel on Climate Change , 2009, Psychological science.

[7]  D. Budescu,et al.  Consistency in interpretation of probabilistic phrases , 1985 .

[8]  S. Broomell,et al.  Effective communication of uncertainty in the IPCC reports , 2012, Climatic Change.

[9]  Ulrike Hahn,et al.  Estimating the probability of negative events , 2009, Cognition.

[10]  Wibecke Brun,et al.  Verbal probabilities: Ambiguous, context-dependent, or both? , 1988 .

[11]  Marie Juanchich,et al.  Risk communication on shaky ground. , 2012, Science.

[12]  Marie Juanchich,et al.  Improbable outcomes: Infrequent or extraordinary? , 2013, Cognition.

[13]  Timothy S. Doupnik,et al.  Interpretation of uncertainty expressions: a cross-national study , 2003 .

[14]  R. Ranyard,et al.  Chinese and English Speakers’ Linguistic Expression of Probability and Probabilistic Thinking , 1999 .

[15]  A. Patt,et al.  Communicating uncertainty: lessons learned and suggestions for climate change assessment , 2005 .

[16]  Helmut Jungermann,et al.  Rarely occurring headaches and rarely occurring blindness: Is rarely=rarely? The meaning of verbal frequentistic labels in specific medical contexts. , 1996 .

[17]  Ruth Beyth-Marom,et al.  How probable is probable? A numerical translation of verbal probability expressions , 1982 .

[18]  Francis W. Zwiers,et al.  Guidance Note for Lead Authors of the IPCC Fifth Assessment Report on Consistent Treatment of Uncertainties , 2010 .

[19]  Rami Zwick,et al.  Comparing the calibration and coherence of numerical and verbal probability judgments , 1993 .

[20]  Anthony Patt,et al.  Using Specific Language to Describe Risk and Probability , 2003 .

[21]  M. Hulme.  Why we disagree about climate change : understanding controversy, inaction and opportunity , 2009 .

[22]  Michael Smithson,et al.  Never say "not": Impact of negative wording in probability phrases on imprecise probability judgments , 2012, Int. J. Approx. Reason..

[23]  G. Box.  Some Theorems on Quadratic Forms Applied in the Study of Analysis of Variance Problems, I. Effect of Inequality of Variance in the One-Way Classification , 1954 .

[24]  D. C. Howell.  Statistical Methods for Psychology , 1987 .

[25]  E. Weber.  From Subjective Probabilities to Decision Weights: The Effect of Asymmetric Loss Functions on the Evaluation of Uncertain Outcomes and Events , 1994 .