UCL Psychology and Language Sciences


London Judgment and Decision Making seminars

Originally established at UCL in the early 1970’s as a weekly Cognition and Reasoning seminar, it later became an intercollegiate seminar on Language and Cognition in the early 1980’s. The name LJDM was finally coined in 1990, and the group has been running seminars under this name ever since, with lecturers and researchers in and around the UK meeting on a regular basis to discuss judgment and decision making, judgments of likelihood, reasoning, thinking, problem solving, forecasting, risk perception and communication, and other related topics.

Unless specified otherwise, all seminars take place on Wednesdays from 5:15-6:15pm. The seminars in 2022/23 will be held in a hybrid format via zoom as well as in Room 305 at the Psychology Department, University College London (on the corner of Bedford Way, Gordon Square and Torrington Place, London WC1H 0AP). Map.

To get updates on the current schedule and weekly reminders of the seminars, please subscribe to the Risk and Decision mailing list. All are welcome to attend.

Titles, abstracts and recordings (where available) of previous seminars can be found here. 

The LJDM seminar series is supported by

University College London
City, University of London
Kings College London

If you would like to present your research to the group or to suggest a speaker, please contact the organizers:

Academic Year 2022/23

Wednesday 16th November 2022

Prof. John Thogersen (University of Aarhus) 

Positive, negative, or graded sustainability labelling? Which is most effective at promoting a shift towards more sustainable product choices?

Sustainability labels convey information about different product attributes, such as its environmental impact, lifespan, or ethical performance. The labelling can be either positive (only identifying the most sustainable products available on the market), negative (only identifying the least sustainable products available on the market), or graded (comparing the sustainable performance of a product with that of all other products on the market). The goal of this research was to assess the relative performance of these three labelling approaches in terms of influencing product choices. A nationally representative sample of 1,243 consumers from Germany, Spain and the Czech Republic participated in an online discrete choice experiment with real incentives. Compared with positive and negative labels, graded labels were most effective in guiding consumers towards more sustainable product choices. These findings support policy interventions that convey product sustainability with graded labels. This research was done in collaboration with researchers in the EU Commission’s Joint Research Center.

Please click here for seminar. 

Talk recording: https://youtu.be/uJxwjx1jL2g

Wednesday 23rd November 2022 

Kerem Oktar (Princeton University) 

How Beliefs Persist When Millions Disagree

People have the remarkable ability to remain steadfast in their beliefs in the face of societal disagreement. For example, most people remain unmoved in their views regarding the ethics of abortion, the existence of God, or the reality of anthropogenic climate change despite knowing that millions disagree. This has important consequences (e.g., societal polarization), yet its psychological underpinnings are poorly understood. In this talk, I will discuss three experiments that lead to the following conclusions: First, participants are typically aware of societal disagreement about controversial issues, yet overwhelmingly (~90%) do not question their views if asked to reflect on this disagreement. Second, we find that participants rely on distinct ‘paths’ to persist in their views across domains (Experiments 1-2), and that these paths have causal and interdependent effects on the tendency to remain anchored to one’s views (Experiment 3). We also find evidence that questioning one’s view is most likely to occur when all paths to persistence are blocked—which may help explain the ubiquity of persistent societal disagreement.

Please click here for seminar. 

Talk Recording: https://www.youtube.com/watch?v=kMoAxO9djNk

Wednesday 30th November 2022 

Dr. Laura Corbit (University of Toronto) 

Understanding the balance between goal-directed and habitual control

A substantial number of studies now show that experiences such as diet or exposure to drugs promote habitual behavioural control. The shift from flexible to habitual control could be the result of direct effects on the habit system which strengthen stimulus-response learning. Alternatively, the effects could be indirect, acting instead to undermine function of, and control by the goal-directed system thus allowing early control by the habit system. These possibilities are difficult to differentiate with either behavioural or neural tools alone. I will present data from recent studies that are beginning to reveal specific effects of drug or diet exposure on decision-making capacity and behavioral control. Distinguishing between excessive habitual control and weakened goal-directed control will be important for improving behvaioural control following exposure to drugs, certain diets or stress. 

Please click here for seminar. 

Talk Recording: https://youtu.be/ecaCQlDZSPg

Wednesday 7th December 2022

Prof. Dr. Andreas ­Voß (University of Heidelberg) 

A Lévy-Flight Model of Decision Making

Most cognitive models of decision-making assume a continuous process of evidence accumulation. Typically, evidence accumulation is considered noisy, i.e. it is determined by a combination of stimulus information and random noise. The combination of a constant systematic rate of information accumulation and Gaussian noise is described mathematically by a diffusion process, which gives the name to the most influential model of this class, the diffusion model. One problem with the standard diffusion model is that additional processes must be included to explain fast errors typically seen in rapid perceptual decisions. For example, in the diffusion model, we need to introduce the assumption of trial-to-trial variations in the starting point position to explain fast errors. In contrast to this approach, we hypothesise that the process of evidence accumulation itself causes fast errors (e.g., fast guessing). In our model, guessing-like processes in evidence accumulation are reflected by large sudden changes ("jumps") in evidence accumulation. This can be explained mathematically by replacing Gaussian noise with a heavy-tailed noise distribution (e.g., the Cauchy distribution), thereby replacing the diffusion process with a Lévy flight. In a series of experiments, we demonstrate the superior ability of the Lévy-flight model to explain behavioural data from different experimental paradigms.

Please click here for seminar. 

Wednesday 14th December 2022 

Speaker: TBC

Christmas Break

Wednesday 11th January 2023 

Prof. Dr. Joachim ­Funke (University of Heidelberg) 

50 years research on complex problem solving: What are the results? 


Please click here for seminar. 

The slides have been provided by the speaker available for distribution and can be found here.

Wednesday 18th January 2023 

Prof. Julia Nafziger (University of Aarhus) 

Nudging in complex environments (joint with Dan Monster and Alexander Koch)

We study the effects of reminder nudges using a novel experimental approach based on a computer game that aims to promote awareness of food safety and foster risk-reducing behavior among consumers. The game exposes participants to a complex environment in which they have to pay attention to and perform multiple, different kinds of food safety and cooking actions within a short period of time. The set-up allows us to test the effect of reminders not only on the reminded, but also on non-reminded actions and thus to observe whether nudges have (positive or negative) spillovers. Further, it allows us to test the effects of multiple vs. single reminders. We test the effects both in the short and long run, i.e., after the withdrawal of the reminder. We observe that both single and multiple nudges have positive effects in the short run -- multiple reminders more so than single reminders: while they lead to crowding-out of non-reminded actions, the positive effect on reminded action dominates. Yet, after withdrawal of the reminders, the negative spillover effect prevails, while the positive effect becomes very small so that, overall, reminders have no effect.

Talk Recording: https://youtu.be/fKEkUkwhG9I

Wednesday 25th January 2023

Speaker: TBC

Wednesday 1st February 2023 

Dr Avishalom Tor (Notre Dame Law School)

When Should Governments Invest More in Nudging?

Highly influential recent work by Benartzi et al. (2017) argues—based on comparisons of the respective effectiveness and costs of behavioral interventions (or nudges) versus traditional instruments—that nudges offer more cost-effective means than traditional interventions for changing individual behavior to achieve desirable policy goals. These authors further argue that nudges' cost-effectiveness advantage means that governments and other organizations should increase their investments in such instruments to supplement traditional interventions. Yet a closer look at Benartzi et al.’s (2017) own data and analysis reveals that they variously exclude and include key cost elements to the benefit of behavioral instruments over traditional ones and overstate the utility of cost-effectiveness analysis for policy selection. Once these methodological shortcomings are corrected, a reassessment of key policies evaluated by the authors reveals that nudges do not consistently outperform traditional interventions, neither under cost-effectiveness analysis nor under the methodologically required cost-benefit analysis. These illustrative findings demonstrate that governments should strive to conduct cost-benefit analyses of competing interventions, including nudges, to implement the most efficient of the available instruments.

Wednesday 8th February 2023 

Dr Joshua Becker (UCL)

Does communication improve the wisdom of crowds?  It depends on the question

Research on the ‘wisdom of crowds’ has consistently shown that one way to improve the accuracy of numeric estimates such as economic forecasting is by using the average estimate of multiple individual contributors, rather than relying on one single person. However, decades of lab experiments have produced contradictory results about whether and when communication between group members makes the resulting average more accurate or less accurate. Thus despite the existence of over 100k results on Google scholar using the “Delphi method” form of information exchange, we lack clear evidence that this method is actually better than unstructured discussion, or that any form of communication is better than none. This talk will explain contradictions in prior research by showing how emergent network centralization interacts with pre-communication estimate distribution such that communication sometimes increases accuracy and sometimes decreases accuracy. Using a formal model of estimate formation and experimental data, I will argue that the fixed effect paradigm—i.e. the assumption that any form of communication is always either helpful or harmful—must be replaced with a model that depends on the particular estimation task under consideration. I will conclude by discussing some limitations of this model for describing true deliberation, sharing some new research under development, and opening the floor for collaborative speculation and brainstorming on how future research might address these topics.

The seminar is to be held in person at room 305, 26 Bedford Way, UCL.

Talk Recording: https://youtu.be/ilfqaNcECWQ

Reading Week 

Wednesday 22nd February 2023 

Speaker: Dr Venessa Brown (University of Pittsburgh)

Contextual and individual factors affecting exploration/exploitation decisions

In uncertain environments, organisms must decide whether to seek out uncertain, potentially better options (explore) versus exploit known good options. This choice, known as the explore/exploit dilemma, has been shown to be affected by factors such as the choice horizon and form of uncertainty. However, how many features of real-world environments, including cognitive complexity and outcome valence, affect explore/exploit decisions is unknown. Here, I present results from a series of studies examining how people manage the explore/exploit dilemma differently under different forms of cognitive load and when maximizing rewards versus minimizing different kinds of losses. I will also show how individual differences, notably anxiety, affect explore/exploit behavior.

Please click here for seminar. 


Wednesday 1st March 2023

No LJDM this week.

Wednesday 8th March 2023

No LJDM this week.

Wednesday 15th March 2023

Dr Felix Cheung (University of Toronto)

Psychology at Times of War and Conflict

Abstract: The Russo-Ukrainian War has far-reaching consequences for the world. Not only has the War changed life in Ukraine drastically, but it has also led to the prioritization of military spending, the reconsideration of the role of international coalitions, and the additional scrutiny of refugee policies. This talk highlights 4 studies that address these issues using diverse samples across continents (total N = 1,382,294). The first study drew on representative data from 16,404 Ukrainian participants and documented Ukrainians’ historical resilience during the 2013-2014 Euromaidan Protest. The second study showed that diverting public spending towards the military poses a well-being cost to citizens. The third study found both short- and long-term well-being benefits for joining the EU. The fourth study examined the refugee crisis and found no evidence that greater influx of refugees is related to poorer life satisfaction in the host populations. Together, these studies 1) introduce new conceptual insights and methodological advances on the psychology of war and conflict, 2) question the temporal generalizability of psychology, and 3) call for the prioritization of psychological research towards pressing global affairs.

Please click here for seminar. 

Wednesday 22nd March 2023

No LJDM this week.


Easter Break

Wednesday 26th April 2023

Daryl O'Connor (University of Leeds)

Stress: The Quiet Killer 

This talk will argue that stress may indirectly contribute to health risk and reduced longevity to the extent that it produces deleterious changes in diet and/or helps maintain maladaptive health behaviours as well as directly by influencing biological processes across the life span (e.g., blood pressure, hypothalamic-pituitary-adrenal (HPA) axis functioning). Studies investigating the relationship between chronic stress, perseverative cognition, the cortisol response and health outcomes will be presented. The second half of the talk will describe work investigating the effects of childhood trauma and the role of HPA axis responses to stress in vulnerability to suicide as well as recent studies into the mental health effects of COVID-19. The importance of studying the effects of stress across the life course and developing stress management interventions will also be highlighted.

Please click here for seminar. 


Wednesday 3rd May 2023

Speaker and Title: TBC



Wednesday 10th May 2023

Patricia Sanchez (University of Toronto)

Title and Abstract: TBC

Please click here for seminar. 


Wednesday 17th May 2023

Neil Bramley (University of Edinburgh)

Title and Abstract: TBC

The seminar will take place in a hybrid format, both in person at UCL (Room 305, 26th Bedford Way) and online. Please click here for seminar. 


Wednesday 24th May 2023

Rani Moran (Queen Mary University of London)

Title and Abstract: TBC

Please click here for seminar. 


Wednesday 31st May 2023

Speaker and Title: TBC

Wednesday 7th June 2023

Brandi S. Morris (University of Aarhus)

Title and Abstract: TBC

Please click here for seminar. 


Summer Break