Updated 1/1/13

Analogies are a mainstay of human communication and reasoning. In science, Niels Bohr used an analogy with the solar system to explain the structure of atoms. In everyday language, analogies help us make a point effortlessly: It is obvious what it means to say that “Bing Cosby has a velvet voice” or that someone is “as annoying as fingernails on a blackboard”, even though voices aren’t made of fabric and people’s personalities don’t consist of fingernails.

However, there is a flipside to the ease with which people process analogies: Because they are so important to our reasoning and communication, we can sometimes be fooled into perceiving an analogy when there is none—simply because two terms presented in close proximity are similar to each other or are emotionally laden. According to many cognitive theorists those two aspects of the processing of analogies arise because we have two systems of reasoning: One very rapid system that relies on relatively shallow analysis of stimuli, which allows us to respond in situations in which time is at a premium, and another one that requires slow deliberation but is guided by more complex rules. Arguably, the former may be triggered by emotive stimuli, because emotion may serve as a “stopping rule” for reasoning—in a nutshell, the more emotion, the less deliberation.

This distinction between two different modes of reasoning is not just dry laboratory science but can also be observed in the public arena. This can be illustrated with recent public controversy involving some of the most toxic and emotive issues of our times that involved Australia’s only national newspaper (The Australian), the national broadcaster (the ABC), and at least indirectly also me.

In May 2012, The Australian ran an opinion piece by Mr James Delingpole in which he riled against wind energy under the title “wind farm scam a huge cover-up.” Wind turbines actually constitute an increasingly important tool in our arsenal of alternative energy to wean the planet off fossil fuels; however, Mr. Dellingpole begs to differ. Among other arguments, Mr. Delingpole cited an unnamed Australian sheep farmer’s opinion that “The wind-farm business is bloody well near a pedophile ring. They’re f . . king our families and knowingly doing so.”

Yes, that did appear exactly as quoted in The Australian.

The use of “is” to connect one concept (“wind-farm business”) to another (“pedophile ring”) leaves little doubt that this statement was intended as an analogy. Any remaining doubt evaporates with the graphic description of what is being done to families by pedophiles and wind energy alike. By engaging our deliberative system of reasoning, we can identify this analogy quite clearly.

Let’s turn to another apparent analogy that was splattered across The Australian’s front page a few days ago under the headline ”It’s OK to link climate denial to pedophilia, ABC tells ex-chairman”: Did the ABC really draw an analogy between climate denial and pedophilia?

Clearly, some journalists and the ABC’s former chairman thought so. But did this opinion reflect deliberation or might it have been their rapid system misfiring because the emotiveness of the issue got the better of them?

Let’s find out. The ABC’s Science Show on 24 November opened with the words “What if I told you that pedophilia is good for children, or that asbestos is an excellent inhalant for those with asthma? Or that smoking crack is a normal part and a healthy one of teenage life, to be encouraged? You’d rightly find it outrageous. But there have been similar statements coming out of inexpert mouths again and again in recent times, distorting the science.”

The presenter, Robyn Williams, then proceeded to cite an Economist article about American politicians, among them one staunch foe of abortion who believes that the “bodies of women subjected to rape can shut down a pregnancy.”

Only later in the show did Mr. Williams turn to climate change, by interviewing me about my research which seeks to explain why people deny the overwhelming evidence about the fact that the climate is changing and that humans are causing it. (Full disclosure: the interview was pre-recorded and I had no advance knowledge of or input to anything preceding it on air.)

So did the Science Show link pedophilia to climate denial by way of an analogy? Did Mr. Williams suggest that climate denial is akin to pedophilia, the way that wind energy was linked to a pedophile ring in the pages of The Australian?

No.

To see why not, let’s engage our deliberate reasoning system and amend the opening of the Science Show by replacing the emotive trigger words thus: “What if I told you that lamp posts are made of chocolate, or that armchairs are an excellent tranquilizer? Or that tractors make great pets?”

Would this link climate denial to lampposts, armchairs, and tractors?

No. Instead, it links climate denial to statements that most people would recognize as being false or outrageous. Drawing that analogy is appropriate because much of climate denial is recognized as false or outrageous by people who are familiar with the scientific process or the peer-reviewed literature.

This actual analogy was lost on some listeners of the Science Show and the headline writers of The Australian because the emotive keywords of the opening statements overpowered analysis of what was actually said. Instead, the emotive content of the key words triggered the rapid reasoning system and tricked it into perceiving an analogy where there was none.

The ABC, by contrast, engaged its deliberative reasoning system and came to much the same conclusion as the preceding analysis, noting that there is no equivalence between the piece in The Australian and the ABC’s science show.

The saga does not end there.

A few days ago, The Australian received an adjudication by the Australian Press Council against them for likening wind energy to pedophilia in the piece mentioned above. This slap on the wrist was promptly followed by another piece in The Australian by the same author who unrepentantly declared “I stand by every word of the piece – especially the bit about paedophiles. I would concede that the analogy may be somewhat offensive to the paedophile community.”

No ambiguity there, this is the deliberative reasoning system wantingly, and wantonly, drawing an analogy between wind energy and pedophilia.  There really are people like that out there, and they are given an opportunity to publish in Australia’s national newspaper.

But that doesn’t mean The Australian will publish just about anything, however bizarre or pornographic it may be. Far from it, The Australian is quite capable of editorial restraint. For example, they elected not to run the statement from the ABC that very calmly explained the difference between an analogy and emotive short-circuitry.

Update 1/1/13: On the day this post went up, The Australian did publish the letter from the ABC, 3 days after the ABC posted that the letter had been declined. The premise underlying the last paragraph of this post is therefore now outdated and hence no longer valid.

In a previous post, I noted that doubt about the efficacy of government intervention to address HICC may become as much a barrier to action as the denialist strategy of manufacturing doubt about the scientific basis of Human Induced Climate Change (HICC).

In this post I expand on that possibility by describing a few more features of the policy response spectrum.

Let’s consider some of the issues that will occur as realities force the need for a co-ordinated policy response to HICC. As we move along the policy response spectrum from inaction to action, we reach a number of interesting thresholds where shifts in policy positions emerge.  Referring to Figure 2 below, these thresholds points include:

A: This is the extreme denialist position which is typically anti-government, anti-regulation and ideologically opposed to government interventions of most kinds.  The influence of advocates of this  position has been discussed previously by Naomi Oreskes (Oreskes & Conway 2010) and others.

B: Moving further we come to the point where global warming is acknowledged but its anthropogenic cause is denied.  This end of the policy response spectrum maintains that warming is part of the natural cycle of global environmental change and that the recent increase in surface temperatures is not caused by human activity.  Attributing climate change to natural causes means that no policy response is required or even desirable because it will have no effect and consequently be a waste of resources that could be better channelled towards adapting to the impact of unavoidable climate change.

C: The next major threshold is where the scientific evidence for HICC is recognised but the policy response is driven by a market-oriented worldview.  At C a person completely accepts the science behind HICC but rejects government intervention in favour of allowing market forces to drive what changes need to occur. The market here is king and government intervention is seen as inefficient and ineffective because it results in unwarranted costs and unintended consequences that damage business, shrink profits and reduce a society’s economic capacity to do the things it needs to do. Government is seen as the problem not part of the solution.

D: Recognising the need for both government and markets to actively take steps to address HICC is the next key threshold along the policy response spectrum.  At D a person sees government intervention, business regulation and legislated policy as essential elements for guiding markets in the right direction.  Moreover, at D, markets and businesses are also regarded as important players in their own right and that markets can take leadership roles, create technological innovations and produce momentum for change that governments cannot emulate or control.  D is the threshold point where a balanced mix of climate change policy responses, both interventionist and market-based, is acknowledged. 

E: Next comes the position where government is seen as the arbiter of policy settings and that, while consultation with business and community is required, it is the role of government to set the legislative agenda for change.  E is the point at which a person says the implications of HICC are so significant that governments must not just send markets signals through taxation and carbon market mechanisms but must legislate for whole-of-system changes that force business and economic systems towards carbon neutrality.   

F: Moving still further along the spectrum we come to the point where markets are seen as the problem and not part of the solution.  Market forces are seen as completely inadequate for driving the shift towards carbon-neutral economies and that governments must unilaterally require systemic change.  Here the urgency of the climate change issue demands direct and even authoritarian government intervention to shift economies from fossil fuel energy sources to alternative energy systems.         

The ideological and worldview divide between interventionist and free market positions will shift across these different thresholds as the urgency and scale of adequate policy responses grows.  A few points can be made about the current situation in Australia and other countries using this spectrum.

• The major battle over climate is/will not between those who deny and those who accept climate change but between those who want targeted and deliberate action and those who want to leave it to the market. 
• At this point in Australia and in several other countries the battles lines in terms of the public debate still lie somewhere between thresholds B and C. 
• The policy battle, however, is between points C and D – between those who want a mix of government, community and market lead action and those who want to leave it all up to market forces. 
• Policies reliant on market forces are in contention with a more mixed policy response where the government role is formally acknowledged.  This being so, the greatest obstruction to proactive policy development and implementation will not come, and perhaps already does not come, from the denialist position on the spectrum (points A and B) but from those who acknowledge HICC while also advocating for free market solutions. 

I believe that it is from this quarter, from those who agree with HICC and, at the same time, deny the interventionist role of government, who present the biggest obstacle to taking the level of action required to seriously address the climate crisis.   

In the next post, I will explain the reasons underlying this hypothesis by considering the role of worldviews and ideologies.

Reference

 Oreskes, N & Conway, EM 2010, Merchants of Doubt: How a Handfull of Scientists Obscured the Truth on Issues from Tobacco Smoke to Global Warming, Bloomsbury Press, New York.

The Debunking Handbook has now been translated into the following languages:

Dutch		French		German
Italian		Spanish		Swedish

This post relates to a poster at the American Geophysical Union Meeting in San Francisco in December 2012 that summarizes our work on uncertainty in climate science. (Thursday, 6 December, 1:40 PM – 6:00 PM, Poster Hall, Moscone South).

There is also an oral session on Uncertainty organized by the same team: Wednesday, 5 December, 2:30-3:30, 3003 (Moscone West).

The abstract of the poster is shown below, and it is followed by links to earlier posts on Shapingtomorrowsworld that present the arguments in greater detail:

TITLE: Uncertainty as Knowledge: Constraints on Policy Choices Provided by Analysis of Uncertainty

AUTHORS: Stephan Lewandowsky¹, James Risbey², Michael Smithson³, Ben R Newell⁴

INSTITUTIONS:

1. University Western Australia, Crawley, WA, Australia.
2. CSIRO Marine and Atmospheric Research, Hobart, TAS, Australia.
3. Australian National University, Canberra, ACT, Australia.
4. University of New South Wales, Sydney, NSW, Australia.

ABSTRACT:

Uncertainty forms an integral part of climate science, and it is often cited in connection with arguments against mitigative action. We argue that an analysis of uncertainty must consider existing knowledge as well as uncertainty, and the two must be evaluated with respect to the outcomes and risks associated with possible policy options. Although risk judgments are inherently subjective, an analysis of the role of uncertainty within the climate system yields two constraints that are robust to a broad range of assumptions. Those constraints are that (a) greater uncertainty about the climate system is necessarily associated with greater expected damages from warming, and (b) greater uncertainty translates into a greater risk of the failure of mitigation efforts. These ordinal constraints are unaffected by subjective or cultural risk-perception factors, they are independent of the discount rate, and they are independent of the magnitude of the estimate for climate sensitivity. The constraints mean that any appeal to uncertainty must imply a stronger, rather than weaker, need to cut greenhouse gas emissions than in the absence of uncertainty.

LINKS AND BACKGROUND INFORMATION:

The poster summarizes the points made on this blog over the last 6 months or so. There are several arguments that are worth drawing attention to:

Uncertainty is not your friend. Uncertainty about the evolution of the climate system (operationalized as the variance of the sensitivity distribution) means that things could be worse than anticipated, rather than better. And in the case of the climate system, there is an inherent asymmetry such that uncertainty is more likely to cause nasty surprises than positive outcomes.

There is another aspect of uncertainty that is not altogether comforting: greater uncertainty inescapably means that the damages from unabated climate change are likely to increase. That is, all other variables being equal, greater uncertainty translates into greater expected risk. This fact rests on a single assumption, namely that the function relating global warming to damages is convex (i.e., accelerating), and all extant economic models agree on that point.

We can even relax the convexity assumption when we consider sea level rise. It turns out that for some fairly straightforward and inescapable mathematicaly reasons, the risk of inundation increases with the uncertainty of future sea level rises. Once again, all other things being equal, greater uncertainty implies greater risk.

Finally, uncertainty is also not a friend when it comes to mitigation. All other things being equal, greater uncertainty means a greater risk that mitigation might fail. A mitigation failure is said to occur when the carbon budget that would limit temperature increases to any agreed maximum is already exhausted by the time mitigation commences. This represents a failure because emissions cannot cease over night—by definition, therefore, mitigation will fail because we will necessarily exceed our budget. It is the probability of such failure that increases with greater uncertainty.

The bottomline of all those strands of argument is that greater uncertainty means greater risk. Greater risk of damages and greater risk of mitigation failure. Any appeal to uncertainty therefore implies a greater need to cut emissions than if uncertainty were smaller.

What does “frankenstorm” Sandy have to do with smoking? Well, quite a bit actually, in an indirect way. I talk about the underlying cognition of tobacco and climate change here, for the Australian Broadcasting Corporation.

The embargo on my latest paper on the cognition of climate change, published in Nature Climate Change, has now been lifted. The paper and abstract are available using the doi: 10.1038/10.1038/NCLIMATE1720.

The paper is entitled “The pivotal role of perceived scientific consensus in acceptance of science”, and its abstract reads as follows:

Although most experts agree that CO2 emissions are causing anthropogenic global warming (AGW), public concern has been declining. One reason for this decline is the ‘manufacture of doubt’ by political and vested interests, which often challenge the existence of the scientific consensus. The role of perceived consensus in shaping public opinion is therefore of considerable interest: in particular, it is unknown whether consensus determines people’s beliefs causally. It is also unclear whether perception of consensus can override people’s ‘worldviews’, which are known to foster rejection of AGW. Study 1 shows that acceptance of several scientific propositions—from HIV/AIDS to AGW—is captured by a common factor that is correlated with another factor that captures perceived scientific consensus. Study 2 reveals a causal role of perceived consensus by showing that acceptance of AGW increases when consensus is highlighted. Consensus information also neutralizes the effect of worldview.

There are a number of interesting aspects to the results, and I am highlighting three that I find particularly noteworthy or intriguing.

The first one is the finding that people’s attitudes towards science are a mixture of specific opinions (i.e., how much people endorse climate science or the link between tobacco and lung cancer) as well as a general factor (i.e., how much people endorse scientific propositions in general). This is quite interesting because it means that there is something about science in general that (partially) determines people’s acceptance of scientific propositions about issues as diverse as tobacco, HIV, and climate.

We furthermore showed that this general factor capturing acceptance of science was correlated with another general factor that represented perceived consensus among scientists. That is, the public’s views on science are at least partially driven by the extent to which people perceive agreement among scientists.

This correlation is neither surprising nor entirely new, as other researchers have reported similar results for climate science (although no one has previously reported the involvement of a general factor). It also explains why climate deniers expend considerable effort to negate the existence of that consensus, using the usual array of deceptive techniques such as pseudo-experts, or pointing to unreviewed blog-posts as “evidence” for their contrarian positions.

The second intriguing finding is that when people were explicitly informed about the scientific consensus on climate change, they became significantly more likely to endorse the basic premise of global warming, and they attributed a larger share of the observed warming trend to human CO2 emissions, than people in a control condition who received no such information. This result suggests that consensus information causally contributes to people’s acceptance of scientific propositions.

The final intriguing finding was that the effect of the consensus information was particularly effective for people whose “free-market” worldview predisposed them to reject climate science. It has long been known that personal ideology or “worldview” is a major driver of people’s attitudes towards climate change: the more strongly people endorse a “fundamentalist” view of the free market, the more likely they are to reject climate science. The role of worldview presents a formidable challenge to science communicators because ideology may override any factual information. Worse yet, the provision of factual information may lead to “backfire” effects that reduce—rather than enhance—acceptance of science among people with extreme worldviews.

The fact that in our study, the provision of consensus information attenuated the role of worldview and increased acceptance particularly among people who maximally endorsed the free market may therefore present an avenue to overcome the communication challenge faced by climate scientists.

The Australian Communications and Media Authority (ACMA) is best known for its reliance on feather dusters to “achieve active self-regulation” by the radio industry. In a notable development today, ACMA traded in the feather duster for some chalk and a blackboard when announcing that one of the nation’s most notorious Shock Jocks, a certain Alan Jones of station 2GB in Sydney, will be given basic training in journalism. This training will presumably introduce Mr.Jones to subtle distinctions such as the difference between a fact and a falsehood.

The ruling is notable for its succinctness and clarity:

New measures applying to programs hosted by Alan Jones

• Pre-broadcast fact-checking by the program’s executive producer of any material provided by non-media sources or third parties which may require additional confirmation and attribution.
• Creation and retention (for at least six weeks) of records of the verification material sourced by the executive producer for the facts contained in the editorial piece.
• Identification by the executive producer of controversial issues of public importance that are not covered by other 2GB current affairs programs.
• Communication of these exceptions to 2GB’s program director who will then be responsible to ensure that another current affairs program presents an alternative, significant viewpoint to that presented in the program hosted by Alan Jones so that 2GB can discharge its obligations under the Commercial Radio Codes of Practice.
• Creation and retention of records by the program director for the above steps.

New measures applying to all news and current affairs programs

• The program director will conduct random checks of daily broadcasts for each of the programs and will record the details of the controversial issues of public importance canvassed in the program. The program director will also record the reasonable efforts made/opportunities that have been given by the relevant programs to present significant alternative viewpoints.
• Training will be conducted (including with Alan Jones) focussing on the ACMA’s findings concerning factual accuracy and significant viewpoints.
• The training will be completed by the end of November 2012.

Apparently that training will be organized by 2GB but will involve an “external provider.” ACMA has asked for confirmation that the training has taken place but it is unknown whether this confirmation will involve any sort of assessment, such as a spelling contest or gold stars.

To put this into context, it must be noted that Mr. Jones is a “patron” of the Australian Galileo Movement, which heralds him for his “long history of speaking out for the downtrodden and for protecting freedom”, and which believes that “his innate expertise straddles the fields of politics, sport and the media.” (This is not necessarily good news because innate traits, such as the lengths of one’s arms or nose, sometimes resist modification by a few weeks of training. But then again, the notion of “innate expertise” is itself an oxymoron based on what we know about expertise acquisition, so maybe they shouldn’t be too concerned.)

By the way, the Galileo Movement’s self-proclaimed mission includes the “Restoration of Morality & Justice” (in addition to a few other minor projects, such as denying climate science). That Restoration was recently delayed when their other media champion, Mr. Andrew Bolt, discovered that he would have no part of the anti-Semitic conspiracy theories sprouted by the Galileos. Mr. Bolt abandoned the Movement to pursue his own version of morality and justice while blogging for a Murdoch tabloid.

And now it looks like the Galileos lost their last remaining media champions to their greatest enemies, reality and facts.

But not to worry, there is always another theory waiting to be sprouted.

Today’s headline in The Age, one of Australia’s major newspapers, is Power pollution plunges. The article notes that the introduction of a price on carbon (currently $23/tonne) may have contributed to a fairly sharp drop in emissions intensity (i.e., the amount of of CO2 emitted per unit power generated). The article is accompanied by the following graph:

There is some interesting debate in the article concerning the underlying reasons; in addition to the carbon tax, there has also been an overall decline in power consumption, which may have had an indirect effect on emissions intensity by permitting generators to turn off old and particularly polluting plants.

The decline in emissions intensity can only be considered good news. The reality of this decline also provides an interesting counterpoint to the intense and fact-free scare campaign that preceded introduction of the carbon tax. It remains to be seen how public opinion will evolve over this issue, although one of the individuals involved in that earlier relentless campaign is presently in considerable trouble over remarks so tasteless that even his long-time sponsors withheld advertising on his radio show.

However, this welcome decline in emissions intensity should not obscure the fact that Australia’s emissions are still among the highest in the world as I showed earlier. The graph below, reproduced from that earlier post, puts our polluting record into a global context:

We are still not doing much better than India, although we beat Botswana and Cambodia. (Note that the axis in this graph is in g/kWh whereas The Age reports t/MW, and note that this graph is for the country as a whole whereas The Age reports Victoria only. This explains the different units and slight divergence of values. Note also that the values in this graph are slightly older; see original post for details.)

So the sky hasn’t fallen in.

We are cutting emissions intensity without any apparent harm to the economy.

But we have a long way to go to catch up with the other 135 countries that generate power more cleanly than Australia.

When you drop a glass it’ll crash to the floor. Wherever you are on this planet, and whatever glass it is you were disposing of, gravity will ensure its swift demise. The replicability of phenomena is one of the hallmarks of science: once we understand a natural “law” we expect it to yield the same outcome in any situation in which it is applicable. (This outcome may have error bars associated with it but that doesn’t affect our basic conclusion).

Nobel-winning cognitive scientist Dan Kahneman recently voiced his concern about the apparent lack of replicability of some results in an area of social psychology that concerns itself with “social priming”, the modification of people’s behavior without their awareness. For example, it has been reported that people walk out of the lab more slowly after being primed with words that relate to the concept “old age” (Bargh et al., 1996). Alas, notes Kahneman, those effects have at least sometimes failed to be reproduced by other researchers. Kahneman’s concern is therefore understandable.

How can experiments fail to replicate? There are several possible reasons but here we focus on the role of inferential statistics in scientific research generally. It isn’t just social psychology that relies on statistics; many other disciplines do too. In a nutshell, statistics enables us to decide whether or not an observed effect has occurred simply by chance. Researchers routinely test whether an observed effect is “significant”. A “significant” effect is one that is so large that it is unlikely to arise from chance alone. An effect is declared “significant” if the probability to observe an effect this large or larger by chance alone is smaller than a pre-defined “significance level”, usually set to 5% (.05).

So, statistics can help us decide whether people walked down the hallway more slowly by chance or because they were primed by “old” words. However, our conclusion that the effect is “real” and not due to chance is inevitably accompanied by some uncertainty.

Here is the rub: if the significance level is .05 (5%), then there is still a 1 in 20 chance that we erroneously concluded the effect was real even when it was due to chance—or put another way, out of 20 experiments, there may be 1 that reports an effect when in fact that effect does not exist. This possibility can never be ruled out (although the probability can be minimized by various means).

There is one more catch: as an experimenter, when reporting a single experiment, one can never be 100% sure whether one’s effect is real or due to chance. One can be very confident that the effect is real if it is extremely unlikely to observe such an effect by chance alone, but the possibility that one’s experiment will fail to replicate can never be ruled out with absolute certainty.

So does this mean that we can never be sure of the resilience of an effect in psychological research?

No.

Quite on the contrary, we know much about how people function and how they think.

This is readily illustrated with Dan Kahneman’s own work, as he has produced several benchmark results in cognitive science. Consider the following brief passage about a hypothetical person called Linda:

Linda is 31 years old, single, outspoken, and very bright. She majored in philosophy. In university, she was involved in several social issues, including the environment, the peace campaign, and the anti-nuclear campaign.

Do you think Linda is more likely to be a bank teller or a bank teller and an active feminist?

Every time this experiment is done—and we have performed it literally dozens of times in our classes—most people think Linda is more likely to be a feminist bank teller than a mere bank teller. After all, she was engaged in environmental issues, wasn’t she?

However, this conclusion is false, and people’s propensity to endorse it is known as the “conjunction fallacy” (Tversky & Kahneman, 1983). It’s a fallacy because an event defined by multiple conditions can never be more likely than an event requiring only one of the constituent conditions: Because there are bound to be some bank tellers who are not feminists, Linda is necessarily more likely to be a bank teller than a bank teller and an active feminist.

Replicable effects such as the conjunction fallacy are obviously not confined to cognitive science. In climate science, for example, the iconic “hockey stick” which shows that the current increase in global temperatures is unprecedented during the past several centuries if not millennia, has been replicated numerous times since Mann et al. published their seminal paper in 1998. (Briffa et al., 2001; Briffa et al., 2004; Cook et al. 2004; D’Arrigo et al., 2006; Esper et al., 2002; Hegerl et al., 2006; Huang et al., 2000; Juckes et al., 2007; Kaufman et al., 2009 ; Ljungqvist, 2010; Moberg et al., 2005; Oerlemans, 2005 ; Pollack & Smerdon, 2004; Rutherford et al., 2005; Smith et al., 2006).

Crucially, those replications relied on a variety of proxy measures to reconstruct past climates—from tree rings to bore holes to sediments and so on. The fact that all reconstructions arrive at the same conclusion therefore increases our confidence in the robustness of the hockey stick. The sum total of replications has provided future generations with a very strong scientific (and moral) signal by which to evaluate our collective response to climate change at the beginning of the 21st century.

Let us now illustrate the specifics of the process of replication within the context of one of my recent papers, with colleagues Klaus Oberauer and Gilles Gignac, which showed (among other things) that conspiracist ideation predicted rejection of a range of scientific propositions, from the link between smoking and lung cancer to the fact that the globe is warming due to human greenhouse gas emissions. This effect was highly significant but the possibility that it represented a statistical fluke—though seemingly unlikely—cannot be ruled out.

To buttress one’s confidence in the result, a replication of the study would thus be helpful.

But that doesn’t mean it should be the same exact study done over again. On the contrary, this next study should differ slightly, so that the replication of the effect would underscore its breadth and resilience, and would buttress its theoretical impact.

For example, one might want to conduct the study using a large representative sample of the U.S. population. The kind of sample that professional survey and market research companies specialize in.

One might refine the set of items based on the results of the first study. One might provide a “neutral” option for the items this time round: the literature recognizes both strengths and weaknesses of including a neutral response option, so running the survey both ways and getting the same result would be particularly helpful.

One might also expand the set of potential worldview predictors, and one might query other controversial scientific propositions, such as GM foods and vaccinations—both said to be rejected by the political Left even though data on that claim are sparse.

Yes, such a replication would be quite helpful.

References

Bargh, J. A., Chen, M., & Burrows, L. (1996). Automaticity of social behavior: Direct effects of trait construct and stereotype activation on action. Journal of Personality and Social Psychology, 71, 230-244.

Briffa, K.R., et al., 2001: Low-frequency temperature variations from a northern tree ring density network. J. Geophys. Res., 106(D3), 2929–2941.

Briffa, K.R., T.J. Osborn, and F.H. Schweingruber, 2004: Large-scale temperature inferences from tree rings: a review. Global Planetary Change, 40(1–2), 11–26.

Cook, E.R., J. Esper, and R.D. D’Arrigo, 2004a: Extra-tropical Northern Hemisphere land temperature variability over the past 1000 years. Quat.Sci. Rev., 23(20–22), 2063–2074.

D’Arrigo, R., R. Wilson, and G. Jacoby, 2006: On the long-term context for late twentieth century warming. J. Geophys. Res., 111(D3), doi:10.1029/2005JD006352.

Esper, J., E.R. Cook, and F.H. Schweingruber, 2002: Low-frequency signals in long tree-ring chronologies for reconstructing past temperature variability. Science, 295(5563), 2250–2253.

Hegerl, G.C., T.J. Crowley, W.T. Hyde, and D.J. Frame, 2006: Climate sensitivity constrained by temperature reconstructions over the past seven centuries. Nature, 440, 1029–1032.

Huang, S. and Pollack, H. S. and Shen, P.-Y. (2000). Temperature trends over the past five centuries reconstructed from borehole temperatures. Nature, 403, 756-758.

Juckes, M. N. et al. (2007). Millennial Temperature Reconstruction Intercomparison and  Evaluation. Climate of the Past, 3, 591–609.

Kaufman, D. S. et al. (2009). Recent Warming Reverses Long-Term Arctic Cooling. Science, 325, 1236.

Ljungqvist, F. C. (2010). A New Reconstruction of Temperature Variability in the Extra-tropical Northern Hemisphere During the Last Two Millennia. Geografiska Annaler , 92A, 339–351.

Mann, M. E., Bradley, R. S., & Hughes, M. K. (1998). Global-Scale Temperature Patterns and Climate Forcing over the Past Six Centuries. Nature, 392, 779–787.

Moberg, A., et al., 2005: Highly variable Northern Hemisphere temperatures reconstructed from low- and high-resolution proxy data. Nature, 433(7026), 613–617.

Oerlemans, J., 2005: Extracting a climate signal from 169 glacier records. Science, 308(5722), 675–677.

Pollack, H.N., and J.E. Smerdon, 2004: Borehole climate reconstructions: Spatial structure and hemispheric averages. J. Geophys. Res., 109(D11), D11106, doi:10.1029/2003JD004163.

Smith, C. L. and Baker, A. and Fairchild, I. J. and Frisia, S. and Borsato, A. (2006). Reconstructing hemispheric-scale climates from multiple stalagmite records. International Journal of Climatology, 26, 1417 – 1424.

Tversky, A., & Kahneman, D. (1983). Extensional versus intuitive reasoning: The conjunction fallacy in probability judgment. Psychological Review, 90, 293-315.

Wahl, E. R. and Ammann, C. R. (2007).  Robustness of the Mann, Bradley, Hughes reconstruction of Northern Hemisphere surface temperatures: Examination of criticisms based on the nature and processing of proxy climate evidence. Climatic Change, 85, 33-69.

Together with colleagues Ullrich Ecker, Colleen Seifert, Norbert Schwarz, and John Cook I recently published a review paper of the literature on misinformation—why does misinformation “stick” to people’s memories? Why would anyone believe patent nonsense, such as the claim that President Obama was born outside the U.S.? And how can we help people discard such erroneous beliefs?

The citation for the paper can be found below, and here are links to a fairly extensive follow-up interview conducted by the American Psychological Society:

• Part 1
• Part 2

Reference

Lewandowsky, S.; Ecker, U. K. H.; Seifert, C.; Schwarz, N. & Cook, J. (2012). Misinformation and its Correction: Continued Influence and Successful Debiasing. Psychological Science in the Public Interest, 13, 106-131.