John Kerr

• PhD
• Senior Research Fellow at University of Otaog Wellington

Despite an overwhelming scientific consensus, a sizable minority of people doubt that human activity is causing climate change. Communicating the existence of a scientific consensus has been suggested as a way to correct individuals’ misperceptions about human-caused climate change and other scientific issues, though empirical support is mixed. We...

Public opinion regarding scientific developments such as genetically modified (GM) food can be mixed. We suggest such science-based technological innovations are rejected by some because they are perceived to be advanced as part of a conspiracy. In nationally representative samples (Australia n=1,011; New Zealand n=754) we report the associations b...

The success of mass COVID-19 vaccination campaigns rests on widespread uptake. However , although vaccinations provide good protection, they do not offer full immunity and while they likely reduce transmission of the virus to others, the extent of this remains uncertain. This produces a dilemma for communicators who wish to be transparent about ben...

Previous research has highlighted how ideological factors such as political self-identification, religiosity and conspiracy thinking influence our beliefs about scientific issues such as climate change and vaccination. Across three studies (combined N = 9,022) we expand on this line of inquiry to show for the first time that the ideological attitud...

The World Health Organization has declared the rapid spread of COVID-19 around the world a global public health emergency. It is well-known that the spread of the disease is influenced by people's willingness to adopt preventative public health behaviors, which are often associated with public risk perception. In this study, we present the first as...

Introduction: Lived experience of negative environmental change can evoke distress called ‘solastalgia’. Worldwide, people are reporting emotional challenges relating to awareness of current and continued environmental decline, even without a lived direct experience of climate change. Our research examines the measurement of anticipatory solastalgi...

Replications are important for assessing the reliability of published findings. However, they are costly, and it is infeasible to replicate everything. Accurate, fast, lower-cost alternatives such as eliciting predictions could accelerate assessment for rapid policy implementation in a crisis and help guide a more efficient allocation of scarce rep...

A significant body of research has examined the relationships between political ideology and conspiracy beliefs. Conspiracy theories are often considered the province of “extremist” political positions. Intriguingly, however, several recent studies have demonstrated that people at the midpoint of the left-right self-placement item often displayed e...

Although conspiracy belief may arise from a frustration of psychological needs, research has yet to investigate these relationships over time. Using four annual waves of longitudinal panel data in New Zealand (2019-2022; N = 55,269), we examined the relationship between four psychological needs (namely belonging, control, meaning in life, and self-...

Many conspiracy theories implicate scientists and science. We investigated the impact of exposure to scientific conspiracies about biotechnologies. Across three preregistered online studies ( Ns = 1,000), participants who read information about conspiracies involving agribiotechnology companies or biobank scientists were more likely to endorse cons...

Many conspiracy theories implicate scientists and science. We investigated the impact of exposure to scientific conspiracies about biotechnologies. Across three pre-registered online studies (Ns=1,000), participants who read information about conspiracies involving agribiotechnology companies or biobank scientists were more likely to endorse conspi...

Public trust in scientists may be essential for widespread acceptance of science-based solutions to societal problems, including climate change. Across 68 countries (N = 69,534), individuals expressed less trust in climate scientists than scientists in general. In most countries and overall, conservative political orientation was more strongly asso...

The monological belief system model (Goertzel, 1994) suggests that believing in one conspiracy theory causes a person to be more likely to believe in others. This model has been influential in the literature, but its core causal hypothesis has never been credibly tested. We therefore tested it in two longitudinal studies. Study 1 used a sample from...

Stories have been shown to be engaging and aid the comprehension and retention of information. However, the persuasive power of storytelling is well-recognized. Is this an inherent property? Can a narrative be constructed that helps people engage with information but does not persuade them? We presented participants (n = 1309) with information abou...

Recent research has produced a significant body of knowledge about the antecedents and consequences of individual differences in belief in conspiracy theories. What is less clear, however, is the extent to which individuals’ beliefs in conspiracy theories vary over time (i.e., within-person variation). In this descriptive and exploratory study, we...

Scientific information is crucial for evidence-based decision-making. Public trust in science can help decision-makers act based on the best available evidence, especially during crises such as climate change or the COVID-19 pandemic 1,2. However, in recent years the epistemic authority of science has been challenged, causing concerns about low pub...

Science is integral to society because it can inform individual, government, corporate, and civil society decision-making on issues such as climate change. Yet, public distrust and populist sentiment may challenge the relationship between science and society. To help researchers analyse the science society nexus across different cultural contexts,...

Scientific information is crucial for evidence-based decision-making. Public trust in science can help decision-makers act based on the best available evidence, especially during crises such as climate change or the COVID-19 pandemic. However, in recent years the epistemic authority of science has been challenged, causing concerns about low public...

This review provides an overview of concepts relating to the communication of statistical and empirical evidence in times of crisis, with a special focus on COVID-19. In it, we consider topics relating to both the communication of numbers, such as the role of format, context, comparisons, and visualization, and the communication of evidence more br...

Uncertainty around statistics is inevitable. However, communicators of uncertain statistics, particularly in high-stakes and potentially political circumstances, may be concerned that presenting uncertainties could undermine the perceived trustworthiness of the information or its source. In a large survey experiment (Study 1; N = 10 519), we report...

Interest in the psychology of misinformation has exploded in recent years. Despite ample research, to date there is no validated framework to measure misinformation susceptibility. Therefore, we introduce Verification done, a nuanced interpretation schema and assessment tool that simultaneously considers Veracity discernment, and its distinct, meas...

This review provides an overview of concepts relating to the communication of statistical and empirical evidence in times of crisis, with a special focus on COVID-19. In it, we consider topics relating both to the communication of numbers -- such as the role of format, context, comparisons, and visualization -- and the communication of evidence mor...

Replication is an important “credibility control” mechanism for clarifying the reliability of published findings. However, replication is costly, and it is infeasible to replicate everything. Accurate, fast, lower cost alternatives such as eliciting predictions from experts or novices could accelerate credibility assessment and improve allocation o...

Misinformation carries the potential for immense damage to public understanding of science and for evidence-based decision making at an individual and policy level. Our research explores the following questions within seismology: which claims can be considered misinformation, which are supported by a consensus, and which are still under scientific...

Does clear and transparent communication of risks, benefits, and uncertainties increase or undermine public trust in scientific information that people use to guide their decision-making? We examined the impact of reframing messages written in traditional persuasive style to align instead with recent “evidence communication” principles, aiming to i...

A notable challenge of the SARS-CoV-2 pandemic has been public scepticism over the severity of the disease, or even its existence. Such scepticism is politically skewed in the USA, with conservatives more likely to downplay or deny the risks of the virus. However, the hospitalization of President Trump with COVID-19 in October 2020 served as a high...

A substantial minority of the public express belief in conspiracy theories. A robust phenomenon in this area is that people who believe one conspiracy theory are more likely to believe in others. But the reason for this “positive manifold” of belief in conspiracy theories is unclear. One possibility is that a single underlying latent factor (e.g.,...

The COVID-19 pandemic supercharged the spread of fake news, misinformation, and conspiracy theories worldwide. Using a national probability sample of adults from the New Zealand Attitudes and Values Study during 2020 (17–99 years old; M = 48.59, SD = 13.86; 63% women, 37% men; N = 41,487), we examined the associations between agreement with general...

The COVID-19 pandemic supercharged the spread of fake news, misinformation, and conspiracy theories worldwide. Using a national probability sample of adults from the New Zealand Attitudes and Values Study during 2020 (17-99 years old; M=48.59, SD=13.86; 63% women, 37% men; N=41,487), we examined the associations between agreement with general consp...

Recent years have seen an explosion in psychological research on beliefs in conspiracy theories. This research has produced a significant body of knowledge about the antecedents and consequences of inter-individual belief in conspiracy theories. What is less clear, however, is the extent to which individuals’ beliefs in conspiracy theories vary ove...

A substantial minority of the public express belief in conspiracy theories. A robust phenomenon in this area is that people who believe one conspiracy theory are more likely to believe in others. But the reason for this "positive manifold" of belief in conspiracy theories is unclear. One possibility is that a single underlying latent factor (e.g. "...

The SARS-CoV-2 pandemic has been the worst infectious disease outbreak in the U.S. in over 100 years and was associated with the deaths of over 500,000 people in the U.S. within its first year alone. This public health challenge is additionally affected by public scepticism over the severity of the disease, or even its existence in many countries,...

Chinn and Hart (2021) argue that their experiment on the effects of communicating the scientific consensus on climate change revealed “mixed” and “inconsistent findings”. We note that Chinn and Hart (2021) provide clear and consistent evidence that the scientific consensus message has positive indirect effects on climate beliefs, attitudes, and sup...

A growing body of research indicates that transparent communication of statistical uncertainty around facts and figures does not undermine credibility. However, the extent to which these findings apply in the context of the COVID-19 pandemic--rife with uncertainties--is unclear. In a large international survey experiment, (Study 1; N = 10,519) we r...

Chinn and Hart (2021) conclude that communicating the scientific consensus on climate change causes psychological reactance. Here we identify several issues that cast doubt on these findings. First and foremost, the authors replicate the finding from van der Linden, Maibach, et al. (2019) that consensus messages do not increase perceptions of manip...

The Gateway Belief Model (GBM) places perception of a scientific consensus as a key “gateway cognition” with cascading effects on personal beliefs, concern, and ultimately support for public policies. However, few studies seeking to evaluate and extend the model have followed the specification and design of the GBM as originally outlined. We presen...

Objective Describe demographical, social and psychological correlates of willingness to receive a COVID-19 vaccine. Setting Series of online surveys undertaken between March and October 2020. Participants A total of 25 separate national samples (matched to country population by age and sex) in 12 different countries were recruited through online...

Interest in the psychology of misinformation has exploded in recent years. Despite ample research, to date there is no psychometrically validated instrument to measure people’s ability to detect misinformation. To overcome this, we introduce the Verification done framework, an overarching interpretation schema, that simultaneously considers overall...

As increasing amounts of data accumulate on the effects of the novel coronavirus SARS-CoV-2 and the risk factors that lead to poor outcomes, it is possible to produce personalized estimates of the risks faced by groups of people with different characteristics. The challenge of how to communicate these then becomes apparent. Based on empirical work...

Public opinion regarding scientific developments such as genetically modified food can be mixed. We suggest such science-based technological innovations are rejected by some because they are perceived to be advanced as part of a conspiracy. In nationally representative samples (Australia n = 1011; New Zealand n = 754), we report the associations be...

Despite calls for political consensus, there is growing evidence that the public response to the COVID-19 pandemic has been politicized in the US. We examined the extent to which this polarization exists among the US public across two national studies. In a representative US sample (N = 699, March 2020) we find that liberals (compared to conservati...

In this study, we present results from five cross-sectional surveys on public risk perception of COVID-19 and its association with health protective behaviours in the UK over a 10-month period (March 2020 to January 2021). Samples were nationally balanced on age, gender, and ethnicity (total N = 6,281). We find that although risk perception varies...

The success of mass COVID-19 vaccination campaigns rests on widespread uptake. However, although vaccinations provide good protection, they do not offer full immunity and while they likely reduce transmission of the virus to others, the extent of this remains uncertain. This produces a dilemma for communicators who wish to be transparent about bene...

Belief in conspiracies is not restricted to the fringe dwellers of society. International research suggests that such beliefs are quite common and that conspiracy theories may serve three basic psychological motives (i.e., epistemic, existential, and relational) for individuals. Yet, little is known about conspiracy theory awareness or belief in Au...

Conspiracism is not restricted to the fringe dwellers of society. International research suggests that such beliefs are quite common and that conspiracy theories may serve three basic psychological motives (i.e., epistemic, existential, and relational) for individuals. Yet, little is known about conspiracy theory awareness or conspiracism in Austra...

Understanding the drivers of vaccine acceptance is crucial to the success of COVID-19 mass vaccination campaigns. Across 25 national samples from 12 different countries we examined the psychological correlates of willingness to receive a COVID-19 vaccine (total N = 25,334), with a focus on risk perception and trust in a number of relevant actors, b...

Misinformation about COVID-19 is a major threat to public health. Using five national samples from the UK (n= 1050 and n= 1150), Ireland (n = 700), the USA (n = 700), Spain (n= 700) and Mexico (n= 700), we examine predictors of belief in the most common statements about the virus that contain misinformation. We also investigate the prevalence of be...

As increasing amounts of data accumulate on the effects of the novel coronavirus Sars-CoV-2 and the risk factors that lead to poor outcomes, it is possible to produce personalised estimates of the risks faced by groups of people with different characteristics. The challenge of how to communicate these then becomes apparent. Based on empirical work...

New Zealand’s primary strategy for tackling greenhouse gas emissions is the emissions trading scheme, which puts a price on emissions from all major industries – except animal agriculture. In the decade since the scheme was introduced, conversations about including emissions from animal agriculture have been shrouded in controversy, with a levy on...

The gateway belief model posits that perceptions of scientific agreement play a causal role in shaping beliefs about the existence of anthropogenic climate change. However, experimental support for the model is mixed. The current study takes a longitudinal approach, examining the causal relationships between perceived consensus and beliefs. Percept...

Full mediation models. (DOCX)

Effects of consensus messages on concern, intentions and policy opinions. (DOCX)

Over the last decade, New Zealand has led the world in the legal sale and uncontrolled use of the recreational drug benzylpiperazine (BZP), the active ingredient of ‘party pills’. One survey found that 40% of 18–29-year-olds admitted to using BZP-based party pills while, in another study, 44% of first-year university students had used the drug. Dur...

Some toxins and drugs can trigger lasting neuroprotective mechanisms that enable neurons to resist a subsequent severe insult. This “pharmacological preconditioning” has far-reaching implications for conditions in which blood flow to the brain is interrupted. We have previously shown that in vitro preconditioning with the AMPA receptor antagonist G...

The spontaneous recessive mutant mouse stargazer has a specific and pronounced deficit in brain-derived neurotrophic factor (BDNF) mRNA expression in the cerebellum. Cerebellar granule cells, in particular, show a selective and near-total loss of BDNF. The mutation involves a defect in the calcium channel subunit Cacng2. This severely reduces expre...