Dan M. KahanYale University
& many others
Research Supported by: National Science Foundation, SES-0922714, SES-06021840 & SES 02-42106 Skoll GlobalThreats
www.culturalcognition.net
Thinking Scientifically About Climate Science Communication
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
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low high
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low high-1.00
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low high-1.00
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point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, 2, 732-35 (2012).
Greater
Lesser
perc
eive
d ris
k (z
-sco
re)
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.
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low high
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low high-1.00
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low high
Greater
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d ris
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PIT prediction: Science Illiteracy & Bounded Rationality
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point 1 point 2
low vs. high sci
High Sci. litearcy/System 2 (“slow”)
Low Sci. litearcy/System 1 (“fast”)
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, 2, 732-35 (2012).
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.
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point 1 point 2
low vs. high sci
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point 1 point 2
low vs. high sci
Lesser Risk
Greater Risk
Science literacy Numeracylow high
perc
eive
d ris
k (z
-sco
re)
low high
PIT prediction PIT prediction
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30b 30t 30b 30t
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30b 30t 30b 30t
actual varianceactual variance
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
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point 1 point 2
low vs. high sci
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point 1 point 2
low vs. high sci
source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, 2, 732-35 (2012).
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
Hierarchy
Egalitarianism
Cultural Cognition Worldviews
Individualism Communitarianism
hierarchical individualists hierarchical communitarians
egalitarian communitariansegalitarian individualists
Risk Perception KeyLow RiskHigh Risk
Hierarchy
Egalitarianism
Abortion procedure
Abortion procedure
Individualism Communitarianism
Environment: climate, nuclear
Guns/Gun Control
Guns/Gun Control
HPV Vaccination
HPV Vaccination
Gays military/gay parenting
Gays military/gay parenting
Environment: climate, nuclear
hierarchical communitarians
egalitarian individualists
Cultural Cognition Worldviews
egalitarian communitarians
Risk Perception KeyLow RiskHigh Risk
cats/annoying varmints
cats/annoying varmints
Source: Kahan, D.M., Jenkins-Smith, H. & Braman, D. Cultural Cognition of Scientific Consensus. J. Risk Res. 14, 147-74 (2011).
Hierarchy
Egalitarianism
Cultural Cognition Worldviews
Risk Perception KeyLow RiskHigh Risk
Individualism Communitarianism
Climate change
Climate change
Nuclear waste disposal
Nuclear waste disposal
Concealed carry bans
Concealed carry bans
Source: Kahan, D.M., Jenkins-Smith, H. & Braman, D. Cultural Cognition of Scientific Consensus. J. Risk Res. 14, 147-74 (2011).
randomly assign 1 “It is now beyond reasonable scientific dispute that human activity is causing ‘global warming’ and other dangerous forms of climate change. Over the past century, atmospheric concentration of carbon dioxide (CO2)—called a “greenhouse gas” because of its contribution to trapping heat—has increased to historically unprecedented levels. Scientific authorities at all major universities agree that the source of this increase is human industrial activity. They agree too that higher C02 levels are responsible for steady rises in air and ocean temperatures over that period, particularly in the last decade. This change is resulting in a host of negative consequences: the melting of polar ice caps and resulting increases in sea levels and risks of catastrophic flooding; intense and long-term droughts in many parts of the world; and a rising incidence of destructive cyclones and hurricanes in others.”
Robert Linden
Position: Professor of Meteorology, Massachusetts Institute of Technology
Education: Ph.D., Harvard University
Memberships:
American Meteorological Society
National Academy of Sciences
“Judged by conventional scientific standards, it is premature to conclude that human C02 emissions—so-called ‘greenhouse gasses’—cause global warming. For example, global temperatures have not risen since 1998, despite significant increases in C02 during that period. In addition, rather than shrinking everywhere, glaciers are actually growing in some parts of the world, and the amount of ice surrounding Antarctica is at the highest level since measurements began 30 years ago. . . . Scientists who predict global warming despite these facts are relying entirely on computer models. Those models extrapolate from observed atmospheric conditions existing in the past. The idea that those same models will accurately predict temperature in a world with a very different conditions—including one with substantially increased CO2 in the atmosphere—is based on unproven assumptions, not scientific evidence. . . .”
Robert Linden
Position: Professor of Meteorology, Massachusetts Institute of Technology
Education: Ph.D., Harvard University
Memberships:
American Meteorological Society
National Academy of Sciences
High Risk(science conclusive)
Low Risk(science inconclusive)
Climate Change
randomly assign 1 “Radioactive wastes from nuclear power plants can be disposed of without danger to the public or the environment through deep geologic isolation. In this method, radioactive wastes are stored deep underground in bedrock, and isolated from the biosphere for many thousands of years. Natural bedrock isolation has safely contained the radioactive products generated by spontaneous nuclear fission reactions in Oklo, Africa, for some 2 billion years. Man-made geologic isolation facilities reinforce this level of protection through the use of sealed containers made of materials known to resist corrosion and decay. This design philosophy, known as ‘defense in depth,’ makes long-term disposal safe, effective, and economically feasible.”
Oliver Roberts
Position: Professor of Nuclear Engineering, University of California, Berkeley
Education: Ph.D., Princeton University
Memberships:
American Association of Physics
National Academy of Sciences
“Using deep geologic isolation to dispose of radioactive wastes from nuclear power plants would put human health and the environment at risk. The concept seems simple: contain the wastes in underground bedrock isolated from humans and the biosphere. The problem in practice is that there is no way to assure that the geologic conditions relied upon to contain the wastes won’t change over time. Nor is there any way to assure the human materials used to transport wastes to the site, or to contain them inside of the isolation facilities, won’t break down, releasing radioactivity into the environment. . . . These are the sorts of lessons one learns from the complex problems that have plagued safety engineering for the space shuttle, but here the costs of failure are simply too high.
Oliver Roberts
Position: Professor of Nuclear Engineering, University of California, Berkeley
Education: Ph.D., Princeton University
Memberships:
American Association of Physics
National Academy of Sciences
Low Risk(safe)
High Risk(not safe)
Geologic Isolation of Nuclear Wastesrandomly assign 1 “Radioactive wastes from nuclear power plants can be disposed of without danger to the public or the environment through deep geologic isolation. In this method, radioactive wastes are stored deep underground in bedrock, and isolated from the biosphere for many thousands of years. Natural bedrock isolation has safely contained the radioactive products generated by spontaneous nuclear fission reactions in Oklo, Africa, for some 2 billion years. Man-made geologic isolation facilities reinforce this level of protection through the use of sealed containers made of materials known to resist corrosion and decay. This design philosophy, known as ‘defense in depth,’ makes long-term disposal safe, effective, and economically feasible.”
Oliver Roberts
Position: Professor of Nuclear Engineering, University of California, Berkeley
Education: Ph.D., Princeton University
Memberships:
American Association of Physics
National Academy of Sciences
“Using deep geologic isolation to dispose of radioactive wastes from nuclear power plants would put human health and the environment at risk. The concept seems simple: contain the wastes in underground bedrock isolated from humans and the biosphere. The problem in practice is that there is no way to assure that the geologic conditions relied upon to contain the wastes won’t change over time. Nor is there any way to assure the human materials used to transport wastes to the site, or to contain them inside of the isolation facilities, won’t break down, releasing radioactivity into the environment. . . . These are the sorts of lessons one learns from the complex problems that have plagued safety engineering for the space shuttle, but here the costs of failure are simply too high.
Oliver Roberts
Position: Professor of Nuclear Engineering, University of California, Berkeley
Education: Ph.D., Princeton University
Memberships:
American Association of Physics
National Academy of Sciences
“So-called ‘concealed carry’ laws increase violent crime. The claim that allowing people to carry concealed handguns reduces crime is not only contrary to common-sense, but also unsupported by the evidence. . . . Looking at data from 1977 to 2005, the 22 states that prohibited carrying handguns in public went from having the highest rates of rape and property offenses to having the lowest rates of those crimes. . . .To put an economic price tag on the issue, I estimate that the cost of “concealed carry laws” is around $500 million a year in the U.S.”
James Williams
Position: Professor of Criminology, Stanford University
Education: Ph.D., Yale University
Memberships:
American Society of Criminologists
National Academy of Sciences
“Overall, ‘concealed carry’ laws decrease violent crime. The reason is simple: potential criminals are less likely to engage in violent assaults or robberies if they think their victims, or others in a position to give aid to those persons, might be carrying weapons. . . . Based on data from 1977 to 2005, I estimate that states without such laws, as a group, would have avoided 1,570 murders; 4,177 rapes; and 60,000 aggravated assaults per year if they had they made it legal for law-abiding citizens to carry concealed handguns. Economically speaking, the annual gain to the U.S. from allowing concealed handguns is at least $6.214 billion.”
James Williams
Position: Professor of Criminology, Stanford University
Education: Ph.D., Yale University
Memberships:
American Society of Criminologists
National Academy of Sciences
High Risk(Increase crime)
Low Risk(Decrease Crime)
Concealed Carry Laws
-80% -60% -40% -20% 0% 20% 40% 60% 80%
Climate Change
Nuclear Waste
Gun Control
Low R
iskH
igh Risk
N = 1,500. Derived from ordered-logit regression analysis, controlling for demographic and political affiliation/ideology variables. Culture variables set 1 SD from mean on culture scales. CIs reflect 0.95 level of confidence
ConcealedCarry
ClimateChange
NuclearPower 31%
54%
22%
58%
61%
72%
Pct. Point Difference in Likelihood of Selecting Response
60% 40% 20% 0 20% 40% 60%
-80%
-60%
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-20%
0%20
%40
%60
%80
%
Clim
ate
Cha
nge
Nuc
lear
Was
te
Gun
Con
trol
Low Risk
High Risk
Egalitarian CommunitarianMore Likely to Agree
Hierarchical IndividualistMore Likely to Agree
Featured scientist is a knowledgeable and credible expert on ...
Hierarchy
Egalitarianism
Cultural Cognition Worldviews
Risk Perception KeyLow RiskHigh Risk
Individualism Communitarianism
Climate change
Climate change
Nuclear waste disposal
Nuclear waste disposal
Concealed carry bans
Concealed carry bans
Hierarchy
Egalitarianism
Cultural Cognition Worldviews
Individualism Communitarianism
Climate change
Climate change
Nuclear waste disposal
Nuclear waste disposal
Perceived Scientific Consensus:Low RiskHigh Risk
Concealed carry bans
Concealed carry bans
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d ris
k (z
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point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
Low Sci lit/numeracy
High Sci lit/numeracy
Cultural Variance
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low high
Hierarchical Individualist
Egalitarian Communitarian
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
Cultural variance conditional on sci. literacy/numeracy?
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low high
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low high
Greater
Lesser
perc
eive
d ris
k (z
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re)
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
Low Sci lit/numeracy
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1.00
low high
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low high
High Sci lit/numeracy
Egalitarian Communitarian
PIT prediction: Culture as heuristic substitute
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1.00
low highHierarchical Individualist
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
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low high
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low high-1.00
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low high
Greater
Lesser
perc
eive
d ris
k (z
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re)
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point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
High Sci lit/numeracy
Actual interaction of culture & sci-lit/num...
Low Sci lit/numeracy
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low high
sci_num
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low high
sci_num
High Sci lit/numeracyEgal Comm
Low Sci/lit numeracyEgal Comm
Low Sci lit/num.Hierarc Individ
High Sci lit/numeracyHierarch Individ
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low high
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
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low high
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low high-1.00
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low high
Greater
Lesser
perc
eive
d ris
k (z
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re)
-1.00
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point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
High Sci lit/numeracy
Low Sci lit/numeracy
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1.00
low high
sci_num
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0.00
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1.00
low high
sci_num
Low Sci lit/num.Hierarc Individ
High Sci lit/numeracyEgal Comm
High Sci lit/numeracyHierarch Individ
-1.00
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0.00
0.25
0.50
0.75
1.00
low high
Low Sci/lit numeracyEgal Comm
Actual interaction of culture & sci-lit/num...
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
-1.00
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low high
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low high-1.00
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low high
Greater
Lesser
perc
eive
d ris
k (z
-sco
re)
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
High Sci lit/numeracy
Low Sci lit/numeracy
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
sci_num
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0.50
0.75
1.00
low high
sci_num
Low Sci lit/num.Hierarc Individ
POLARIZATION INCREASES as scil-lit/numeracy increases
High Sci lit/numeracyEgal Comm
High Sci lit/numeracyHierarch Individ
-1.00
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-0.25
0.00
0.25
0.50
0.75
1.00
low high
Low Sci/lit numeracyEgal Comm
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
Motivated Numeracy
Kahan, D.M. Ideology, Motivated Reasoning, and Cognitive Reflection. Judgment and Decision Making 8, 407-424 (2013)
“Skin cream experiment”
“Skin cream experiment”
“Gun ban experiment”
Four conditions
Numeracy
Conserv_Repub is standardized sum of standardized responses to 5-point liberal-conservative ideology and 7-point party-self-identification measures.
0 1 2 3 4 5 6 7 8 90 1 2 3 4 5 6 7 8 9numeracy
Numeracy scoreEntire Sample
Numeracy scorePolitical outlook subsamples
Conserv_Repub > 0Conserv_Repub < 0
01
corr
ect i
nter
pre
tatio
n of
dat
a (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
Correct interpretation of data
rash decreases
rash increases
Numeracy score
01
corr
ect i
nter
pre
tatio
n of
dat
a (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
Lowess smoother superimposed on raw data.
numeracy score at & above which subjects can be expected to correctly interpret data.
0 1 2 3 4 5 6 7 8 90 1 2 3 4 5 6 7 8 9numeracy
Numeracy scoreEntire Sample
Numeracy scorePolitical outlook subsamples
Conserv_Repub > 0Conserv_Repub < 0
Numeracy
01
corr
ect
inte
rpre
tatio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
rash decreasesrash increases
Numeracy score
01
correct interpretation of data (
=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
Correct interpretation of data
skin treatment
Gun ban
01
corr
ect
inte
rpre
tatio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
rash decreasesrash increases
Numeracy score
01
correct interpretation of data (
=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
01
corr
ect i
nter
pre
tatio
n of
dat
a (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: gun ban
Numeracy score
01
correct interpretation of data (
=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreasescrime increases
Correct interpretation of data
skin treatment
Gun ban
01
n_co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
skin cream
01
correct interpretation of da
ta (=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
rash decreases
rash increasesrash decreases
rash increases
Numeracy score01
n_co
rrect interp
retatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
corre
ct int
erpr
etatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
01
n_correct interpretation of data (=1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
01
n_co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
correct interpretation of data (
=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
Correct interpretation of data
Liberal Democrats (< 0 on Conservrepub) Conserv Republicans (> 0 on Conservrepub)
skin treatment
Gun ban
N = 1111. Outcome variable is “Correct” (0 = incorrect interpretation of data, 1 = correct interpretation). Predictor estimates are logit coefficients with z-test statistic indicated parenthetically. Experimental assignment predictors—rash_decrease, rash_increase, and crime_increase—are dummy variables (0 = unassigned, 1 = assigned—with assignment to “crime decreases” as the comparison condition. Z_numeracy and Conserv_Repub are centered at 0 for ease of interpretation. Bolded typeface indicates predictor coefficient is significant at p < 0.05.
Best fitting regression model for experiment results
rash_decrease 0.40 (1.57)rash increase 0.06 (0.22)crime increase 1.07 (4.02)z_numeracy -0.01 (-0.05)z_numeracy_x_rash_decrease 0.55 (2.29)z_numeracy_x_rash_increase 0.23 (1.05)z_numeracy_x_crime_increase 0.46 (2.01)z_numeracy2 0.31 (2.46)z_numeracy2_x_rash_decrease 0.02 (0.14)z_numeracy2_x_rash_increase -0.07 (-0.39)z_numeracy2_x_crime_increase -0.31 (-1.75)Conserv_Repub -0.64 (-3.95)Conserv_Repub_x_rash_decrease 0.56 (2.64)Conserv_Repub_x_rash_increase 1.28 (6.02)Conserv_Repub_x_crime_increase 0.63 (2.82)z_numeracy_x_Conserv_repub -0.33 (-1.89)z_nuneracy_x_Conserv_Repub_x_rash_decrease 0.33 (1.40)z_nuneracy_x__x_rash_increase 0.54 (2.17)z_nuneracy_x__x_crime_increase 0.26 (1.08)_constant -0.96 (-4.70)
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0142
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0092
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0139
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0081
High numeracyLow numeracy
high numeracy = 8 correctlow numeracy = 3 correct
Regression model predicted probabilities
skin treatment
Gun ban
probabilility of correct interpretation of data probabilility of correct interpretation of data
rash decreases
rash increases
rash decreases
rash increasesrash decreases
rash increases
rash decreases
rash increases
crime increases
crime decreases
crime increases
crime decreases
crime increases
crime decreases
crime increases
Liberal Democrat (-1 SD on Conservrepub)Conserv Republican (+1 SD on Conservrepub)
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
crime decreases
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0142
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0092
Gun ban
probabilility of correct interpretation of data probabilility of correct interpretation of data
crime increases
crime decreases
crime increases
crime decreases
crime increases
crime decreases
crime increases
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
crime decreases
Numeracy magnification of motivated reasoning
Avg. “polarization”on crime data
for high numeracypartisans
46% (± 17%)
Avg. “polarization”on crime data
for low numeracypartisans
25% (± 9%)
High numeracyLow numeracy
High numeracyLow numeracy
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0166
probability of correct interpretation of data
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0223
probability of correct interpretation of data0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0374
probability of correct interpretation of data
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0149
probability of correct interpretation of dataEC rash increases
HI crime decrease
HI crime increase
EC crime decrease
EC crime increase
HI crime decrease
HI crime increase
EC crime decrease
EC crime increase
HI rash increases
HI rash decreases
probabilility of correct interpretation of data probabilility of correct interpretation of data
EC rash decreasesEC rash decreases
EC rash increases
HI rash increases
HI rash decreases
skin treatment
Gun ban
high numeracy = 8 correctlow numeracy = 3 correct
Egalitarian communitarian (-1 SD on Hfac & Ifac)Hierarch individid (+1 SD on Hfac & Ifac)
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
Greater
Lesser
perc
eive
d ris
k (z
-sco
re)
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
High Sci lit/numeracy
Low Sci lit/numeracy
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
sci_num
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
sci_num
Low Sci lit/num.Hierarc Individ
POLARIZATION INCREASES as scil-lit/numeracy increases
High Sci lit/numeracyEgal Comm
High Sci lit/numeracyHierarch Individ
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
Low Sci/lit numeracyEgal Comm
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0071
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0111
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0081
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0121
High numeracyLow numeracy
Skin treatment
Gun ban
probability of correct interpretation of data probability of correct interpretation of data
rash decreasesrash increases
rash decreases
rash increases rash decreases
rash increases
rash decreases
rash increases
crime increasescrime decreases
crime increases
crime decreasescrime decreases
crime increases
Liberal Democrat (-1 SD on Conservrepub) Conservative Republican (+1 SD on Conservrepub)low numeracy = 3 correct/ high numeracy = 7 correct
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
crime decreases
crime increases
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
probabilityof correct interpretation of data0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
probability of correct interpretation of data
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
Greater
Lesser
perc
eive
d ris
k (z
-sco
re)
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
High Sci lit/numeracy
Low Sci lit/numeracy
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
sci_num
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
sci_num
Low Sci lit/num.Hierarc Individ
POLARIZATION INCREASES as scil-lit/numeracy increases
High Sci lit/numeracyEgal Comm
High Sci lit/numeracyHierarch Individ
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
Low Sci/lit numeracyEgal Comm
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
-80% -60% -40% -20% 0% 20% 40% 60% 80%
Climate Change
Nuclear Waste
Gun Control
Low R
iskH
igh Risk
N = 1,500. Derived from ordered-logit regression analysis, controlling for demographic and political affiliation/ideology variables. Culture variables set 1 SD from mean on culture scales. CIs reflect 0.95 level of confidence
ConcealedCarry
ClimateChange
NuclearPower 31%
54%
22%
58%
61%
72%
Difference in Likelihood of Agreeing Scientist is “Expert”
60% 40% 20% 0 20% 40% 60%
-80%
-60%
-40%
-20%
0%20
%40
%60
%80
%
Clim
ate
Cha
nge
Nuc
lear
Was
te
Gun
Con
trol
Low Risk
High Risk
Egalitarian CommunitarianMore Likely to Agree
Hierarchical IndividualistMore Likely to Agree
Featured scientist is a knowledgeable and credible expert on ...
Not too little rationality, but too much.
The science communication problem
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen:
* to the ordinary decisionmaker:
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen:
* to the ordinary decisionmaker:
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen:
* to the ordinary decisionmaker: normal climate science
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen:
* to the ordinary decisionmaker: normal climate science
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen: the normality/
* to the ordinary decisionmaker: normal climate science
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen: the normality/banality
* to the ordinary decisionmaker: normal climate science
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen: the normality/banality of climate science
* to the ordinary decisionmaker: normal climate science
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0071
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0111
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0081
0 .1 .2 .3 .4 .5 .6 .7 .8 .9 1kernel = epanechnikov, bandwidth = 0.0121
High numeracyLow numeracy
Skin treatment
Gun ban
probability of correct interpretation of data probability of correct interpretation of data
rash decreasesrash increases
rash decreases
rash increases rash decreases
rash increases
rash decreases
rash increases
crime increasescrime decreases
crime increases
crime decreasescrime decreases
crime increases
Liberal Democrat (-1 SD on Conservrepub) Conservative Republican (+1 SD on Conservrepub)low numeracy = 3 correct/ high numeracy = 7 correct
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
crime decreases
crime increases
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
probabilityof correct interpretation of data0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
probability of correct interpretation of data
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
Greater
Lesser
perc
eive
d ris
k (z
-sco
re)
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
point 1 point 2
low vs. high sci
“How much risk do you believe climate change poses to human health, safety, or prosperity?”
High Sci lit/numeracy
Low Sci lit/numeracy
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
sci_num
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
sci_num
Low Sci lit/num.Hierarc Individ
POLARIZATION INCREASES as scil-lit/numeracy increases
High Sci lit/numeracyEgal Comm
High Sci lit/numeracyHierarch Individ
-1.00
-0.75
-0.50
-0.25
0.00
0.25
0.50
0.75
1.00
low high
Low Sci/lit numeracyEgal Comm
U.S. general population survey, N = 1,500. Scale 0 (“no risk at all”) to 10 (“extreme risk”), M = 5.7, SD = 3.4. CIs reflect 0.95 level of confidence.source: Kahan, D.M., Peters, E., Wittlin, M., Slovic, P., Ouellette, L.L., Braman, D. & Mandel, G. The polarizing impact of science literacy and numeracy on perceived climate change risks. Nature Clim. Change, advance online publication (2012), doi:10.1038/nclimate1547.
-80% -60% -40% -20% 0% 20% 40% 60% 80%
Climate Change
Nuclear Waste
Gun Control
Low R
iskH
igh Risk
N = 1,500. Derived from ordered-logit regression analysis, controlling for demographic and political affiliation/ideology variables. Culture variables set 1 SD from mean on culture scales. CIs reflect 0.95 level of confidence
ConcealedCarry
ClimateChange
NuclearPower 31%
54%
22%
58%
61%
72%
Difference in Likelihood of Agreeing Scientist is “Expert”
60% 40% 20% 0 20% 40% 60%
-80%
-60%
-40%
-20%
0%20
%40
%60
%80
%
Clim
ate
Cha
nge
Nuc
lear
Was
te
Gun
Con
trol
Low Risk
High Risk
Egalitarian CommunitarianMore Likely to Agree
Hierarchical IndividualistMore Likely to Agree
Featured scientist is a knowledgeable and credible expert on ...
The science communication problem
Not too little rationality, but too much.
01
n_co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
skin cream
01
correct interpretation of da
ta (=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
rash decreases
rash increasesrash decreases
rash increases
Numeracy score
Liberal Democrats (< 0 on Conservrepub) Conserv Republicans (> 0 on Conservrepub)0
1
n_co
rrect interp
retatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
corr
ect i
nter
pret
atio
n of
dat
a (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
Hierarchy
Egalitarianism
Individualism Communitarianism
hierarchical individualists hierarchical communitarians
egalitarian communitariansegalitarian individualists
Cultural Cognition Worldviews
Cultural Cognition Worldviews
-2.5 -2 -1.5 -1 -.5 0 .5 1 1.5 2 2.5Science comprehension score-2.5 -2 -1.5 -1 -.5 0 .5 1 1.5 2 2.5
Science comprehension score
-2.5 -2 -1.5 -1 -.5 0 .5 1 1.5 2 2.5Science comprehension score-2.5 -2 -1.5 -1 -.5 0 .5 1 1.5 2 2.5
Science comprehension score
Hierarchy
Egalitarianism
CommunitarianismIndividualism
01
n_co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
skin cream
01
correct interpretation of da
ta (=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
rash decreases
rash increasesrash decreases
rash increases
Numeracy score01
n_co
rrect interp
retatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
corre
ct int
erpr
etatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
01
n_correct interpretation of data (=1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
Correct interpretation of dataLiberal Democrats (< 0 on Conservrepub) Conserv Republicans (> 0 on Conservrepub)
01
n_co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
skin cream
01
correct interpretation of da
ta (=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
rash decreases
rash increasesrash decreases
rash increases
Numeracy score01
n_co
rrect interp
retatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
corre
ct int
erpr
etatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
01
n_correct interpretation of data (=1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
01
n_co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
correct interpretation of data (
=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
Correct interpretation of dataLiberal Democrats (< 0 on Conservrepub) Conserv Republicans (> 0 on Conservrepub)
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen: the normality/banality of climate science
* to the ordinary decisionmaker: normal climate science
Communicating Normality
Communicating Normality
01
n_co
rrect in
terp
reta
tio
n o
f d
ata
(=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
skin cream
01
correct interpretation of da
ta (=1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
rash decreases
rash increasesrash decreases
rash increases
Numeracy score
Liberal Democrats (< 0 on Conservrepub) Conserv Republicans (> 0 on Conservrepub)
01
n_co
rrect interp
retatio
n of d
ata (=
1)
0 1 2 3 4 5 6 7 8 9n_numeracy
gun ban
Numeracy score
01
corr
ect i
nter
pret
atio
n of
dat
a (=
1)
0 1 2 3 4 5 6 7 8 9numeracy
scatterplot: skin treatment
crime decreases
crime increases
crime decreases
crime increases
1. A plausible but incorrect explanation: the public irrationality thesis (PIT)
2. Another, better one
3. Communicating what to whom about climate science
The science communication problem
: motivated reasoning
* to the ordinary citizen: the normality/banality of climate science
* to the ordinary decisionmaker: normal climate science
Cultural Cognition Cat Scan Experiment
Go to www.culturalcognition.net!