Science (1975)

Humans!

• Cognitively Funky

• Culturally Bizaare

Lichtenstein et al. (1982)

No wonder

scientific

uncertainty is so

strange to people

We VASTLY

underestimate our

own uncertainty of

even simple

judgements

Rabinovich and Morton (2012)

Our response to uncertainty, like

everything, is contextually and culturally

mediated

“Which of the following numbers represents the biggest risk of getting a disease? 1 in 100, 1 in 1000, or 1 in 10?” was answered incorrectly by 25% of U.S. participants and 28% of German participants. (G. Gigerenzer et al. 2007)

H. Sapiens exhibits highly

variable numeracy and

scientific literacy*

*Some people are dumb as bricks

Scientist’s view

of uncertainty is

out of whack

with how

everyone else

thinks

(US Climate Assessment Program 2009)

Know thy audience

“One of the clearest findings in the empirical literature on risk communication is that no one can design effective risk communication messages without some empirical evaluation and refinement of those messages with members of the target audience” (US Climate Assessment Program 2009)

See this:

Numbers – not so simple

Denominator bias/neglect

Be consistent in your presentation of odds or

probabilities.

But present important single values in

multiple ways.

Words: ambiguous but unavoidable

“Graphical features that improve accuracy of quantitative reasoning appear to be different from features that induce behavior change, and features that viewers like may not support either of the two goals” (Ancker et. al. 2006)

Graphics: Not a pancea to actual

communication skills

Uncertainty beyond numbers

“For some problems there comes a time when uncertainty is so high that conventional modes of probabilistic analysis no longer make sense…a much simpler approach, such as a bounding or order- of-

magnitude analysis, might be superior”

“Analysis that yields predictions is very helpful when our knowledge is sufficient to make meaningful predictions. However, the past history of success in such efforts suggests great caution…When meaningful prediction is not possible, alternative strategies, such as searching for responses or policies that will be robust across a wide range of possible

futures, deserve careful consideration.”

“When second-order uncertainty is being considered, one should be very careful to determine that the added level of such complication will aid in, and will not unnecessarily complicate, subsequent use of the

results.”

US Climate Assessment Program (2009)

IPCC 2010