Take part in DART research!

Members of the DART research group regularly conducts behavioural science studies and experiments to better understand how individuals and professionals make decisions, perceive and communicate risks, and innovate to solve problems and to find out how we can improve people’s ability to achieve better outcomes for themselves, at work, and in the wider society.

If you would like to learn about our work and be invited to take part in our studies, you can register your details here. When we run a new study, we will send you an email giving you information about the study and details about what you need to do to participate. Some studies will take place online while others will take place at the Kingston Business School (KT2 7LB).

Thank you for your interest and support!

Motors of vaccination decisions and vaccination advocacy

This project aims to better understand the levels of autonomous drive towards vaccination and vaccination advocacy among health care professionals. We are approaching the problem of vaccine hesitancy from a new angle. Rather than assuming that people getting vaccinated results from a rational decision-making process, we want to understand motivation – why would someone want (or not want) to get vaccinated?

This project has received funding from Sanofi-Pasteur and from Kingston University.

We are currently developing a toolkit to support healthcare employers wishing to reduce vaccine hesitancy and promote vaccination advocacy among their staff. If you would like to learn more, join the vaccination @ work network and a member of DART will be in touch!

In recent years, public opinion shifted from a widespread acceptance of vaccination to an increase in concern for vaccine safety, fuelled by media coverage of alleged vaccination-related risks and the growing influence of anti-vaccine movements.

Such concerns are often based on erroneous or misleading information and vaccination advocates naturally sought to rectify incorrect beliefs by disseminating scientific evidence to the contrary, confident that this would suffice to “immunize” individuals against anti-vaccination arguments.

However, such educative interventions, whether through formal training or informal conversations often seem to further antagonize rather than rally those who already doubt vaccination, leaving advocates feeling at loss for ways to promote the benefits of vaccination.

An alternative perspective consists in considering vaccination as a motivated decision. To further explore this possibility, we have developed two scales: the MoVac© and the MovAd© scales, which aim to measure individual differences in dimensions related to intrinsic motivation to engage in a behaviour.

We have collected data from several populations, including the general public, Sanofi-Pasteur employees, NHS employees at Imperial College Healthcare NHS Trust (in collaboration with Imperial College London), and GPs in Romania (in collaboration with the Romanian Pro Immunization Association (API) and The Romanian National Society of Family Doctors, SNMF)

Research team

Prof Gaëlle Vallée-Tourangeau (PI)
Prof Nick Sevdalis
Prof Suzanne Suggs
Prof Christine Norton
Dr Angus Thomson
Dr Ana Wheelock
Dr Marianne Promberger
Dr Miroslav Sirota
Ms Karis Moon (PhD researcher)

Research outputs

Thomson, A., Vallée-Tourangeau, G., & Suggs, L. S. (2018). Strategies to increase vaccine acceptance and uptake: From behavioral insights to context-specific, culturally-appropriate, evidence-based communications and interventions. Vaccine, 36(44), 6457–6458. https://doi.org/10.1016/j.vaccine.2018.08.031
Vallée-Tourangeau, G., Promberger, M., Moon, K., Wheelock, A., Sirota, M., Norton, C., & Sevdalis, N. (2017). Motors of influenza vaccination uptake and vaccination advocacy in healthcare workers: Development and validation of two short scales. Vaccine. https://doi.org/10.1016/j.vaccine.2017.08.025

Kassianos, G., Kuchar, E., Nitsch-Osuch, A., Kyncl, J., Galev, A., Humolli, I., … Vallée-Tourangeau, G. (2018). Motors of influenza vaccination uptake and vaccination advocacy in healthcare workers: A comparative study in six European countries. Vaccine. https://doi.org/10.1016/j.vaccine.2018.02.031

Thomson, A., Robinson, K., & Vallée-Tourangeau, G. (2015). The 5As: A practical taxonomy for the determinants of vaccine uptake. Vaccine. http://doi.org/10.1016/j.vaccine.2015.11.065

Intuition and the conjunction fallacy

This research is funded by the Leverhulme Trust and aims to explore the circumstances in which faster thinking is more logical than slower deliberative thinking, using the innovative methodology initially reported in Villejoubert (2009). It involves a series of six experimental studies designed to provide evidence that logical considerations do not always require a higher motivation to ‘think harder’, and that, contrary to accepted wisdom, increasing reliance on intuitive thinking or decreasing cognitive resources may in fact serve to improve judgments. This work has the potential to challenge dominant theoretical accounts and current educational strategies for teaching probabilistic reasoning.

As a consequence of the complexity and inherent unpredictability of the world in which they live, humans naturally seek to understand and manage the uncertainty of present and future outcomes. Yet, reasoning under uncertainty exhibits a number of biases and shortcomings (e.g., Villejoubert & Mandel, 2002).The conjunction fallacy is a well-researched example of such suboptimal reasoning. Tversky and Kahneman (1983) illustrated this fallacy with the Linda task, which introduces ‘Linda’ as a single 31 year-old woman, outspoken and very bright, who majored in philosophy, is deeply concerned with issues of discrimination and social justice, and has participated in anti-nuclear demonstrations.

After reading this short description, individuals tend to believe, against the tenets of logic, that a conjunction of two events (e.g., ‘Linda is a feminist and a bank teller’) is more likely to be true than one of the conjunctive events (e.g., ‘Linda is a bank teller’). It is commonly argued that such errors occur because people are not accustomed to engage in effortful and time-consuming analysis but, instead, are often satisfied by plausible judgements arising from rapid intuitive thinking (Kahneman, 2003).

This accepted wisdom presupposes that inadequate judgements occur through lack of motivation or cognitive capacity for engaging in effortful thinking (e.g., Stanovich & West, 2000). However, a recently developed research methodology has produced evidence that challenges this predominant view (Villejoubert, 2009). This innovative experimental procedure permits the examination of the relative impact of heuristic and logical considerations on judgements. Instead of asking participants to make separate evaluations of the probability of a conjunct and the probability of a single event, this procedure asks them to judge whether statements comparing both type of probabilities are correct or incorrect.

These statements vary in terms of their logicality (logical vs. illogical) and their compatibility with the representativeness heuristic (representative vs. unrepresentative). To illustrate, Figure 1 shows results for representative and logical statements (e.g., ‘the fact that Linda is a feminist is more likely than the fact that she is a feminist and a bank teller’) and representative but illogical ones (e.g., ‘the fact that Linda is a feminist and a bank-teller is more likely than the fact that she is a bank teller’).

Participants in Villejoubert’s (2009) study were more likely to accept representative statements but they were also significantly less likely to accept illogical ones. Moreover, they consistently took longer before accepting a statement when heuristic and logical considerations were in conflict, even under time pressure (< 10s; see acceptance times for representative but illogical statements in Fig. 1).

These findings highlight two important features of people’s reasoning: (1) the increase in acceptance time under conflicting situations suggests that people routinely engage in effortful processing and (2) the recurrence of this finding under time pressure suggests that the conflict between heuristic and logical considerations was easily detected.

One possible account of these data would be that intuitive thinking might in fact point to the logical answer first. When this answer conflicts with representativeness, people then engage in effortful and deliberative thinking to resolve the conflict. This hypothesis goes against the traditional two-system theoretical account (e.g., Kahneman, 2003), which stipulates that under time pressure, thinking should be more heuristic and less rational. In contrast, Villejoubert’s (2009) findings suggest that quick thinking can be logical while effortful thinking can be biased by non-logical heuristics.The goal of this research project is therefore to explore more systematically the circumstances in which faster thinking is more logical than slower deliberative thinking, using the innovative methodology initially reported in Villejoubert (2009).


Cacioppo, J. T., Petty, R. E., & Kao, C. F. (1984). The efficient assessment of need for cognition. Journal of
Personality Assessment, 48, 306-307.

De Neys, W. (2006). Dual processing in reasoning: Two systems but one reasoner. Psychological Science, 17, 428-433.

Kahneman, D. (2003). A perspective on judgement and choice: Mapping bounded rationality. American Psychologist, 58, 697-720.

Masicampo, E., & Baumeister, R. F. (2008). Toward a physiology of dual-process reasoning and judgement: Lemonade, willpower, and expensive rule-based analysis. Psychological Science, 19, 255-260.

Stanovich, K. E., & West, R. F. (2000). Individual differences in reasoning: Implications for the rationality debate. Behavioral and Brain Sciences, 23, 645-726.

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

Villejoubert, G. (2009). Are representativeness judgements automatic and rapid? The effect of time pressure on the conjunction fallacy. In N. Taatgen, H. van Rijn, L. Schomaker and J. Nerbonne
(Eds.), Proceedings of the 30th Annual Conference of the Cognitive Science Society (pp. 2980-2985).
Austin, TX: Cognitive Science Society. Retrieved from

Villejoubert, G., & Mandel, D. R. (2002). The inverse fallacy: An account of deviations from Bayes’s theorem and the additivity principle. Memory & Cognition, 30, 171-178.


Politeness, severity and risk communication

This research project explores the effect of conviction severity and conviction base rate on numerical estimates of the uncertainty conveyed by verbal probability phrases.

Research on linguistic probabilities has shown that phrases such as possible can be attributed higher numerical estimates in severe or high base rate events. Research has also built on the pragmatic account of linguistic probabilities, which shows that when verbal probability expressions are interpreted as politeness devices, events are estimated as more likely to occur and as denoting higher risks.

This research project aims to expand upon previous findings in a new area of application; namely the communication of uncertainty in a legal setting. It examines how conviction severity and conviction base rates may influence the interpretation of verbal probability phrases (as a risk communication or a face-management linguistic device) and assessed the degree to which the type of linguistic interpretation favored might influence the perceived likelihood of a suspect’s guilt and of his conviction.

So far, our findings show that whereas an event base rate might have a strong influence on the numerical and linguistic interpretation of verbal probability phrases such as “it is possible that…”, evidence for the impact of severity seems to depend on base-rates.


Bonnefon, J. F., & Villejoubert, G. (2006). Tactful, or doubtful? Expectations of politeness explain the severity bias in the interpretation of probability phrases. Psychological Science, 17, 747-751. doi: 10.1111/j.1467-9280.2006.01776.x



Ms Egle Butt (PI)
Prof Gaëlle Vallée-Tourangeau
Dr Marie Juanchich
Dr Miroslav Sirota


Butt, E., Sirota, M., Juanchich, M., & Vallée-Tourangeau, G. (2016, June). When Are Severe Outcomes More Probable? – Role of Base Rate. Paper presented at the FUR 2016 Conference, Warwick, United Kingdom.

Butt, E., Vallée-Tourangeau, G., Juanchich, M., & Sirota, M. (2015, August). Communicating probability of environmental risk: Accounting for face-threatening contexts. Paper presented at the 25th Subjective Probability, Utility and Decision Making Conference, Budapest, Hungary.

Butt, E., Villejoubert, G., Juanchich, M., & Vallée-Tourangeau, F. (2013, August). The effect of conviction severity and base-rate in interpreting linguistic probability expressions. Paper presented at the 24th Subjective Probability, Utility and Decision Making Conference, Barcelona, Spain.

The effect of interactivity and transfer in insight problem solving

This research aims to investigate whether manipulating interactivity levels would have an effect on performance in an insight problem.

The information-processing model has traditionally described problem solving as an activity where progressive moves are made towards a solution by journeying through a problem space (Newell & Simon, 1972). More recently, Ohlsson (2011) suggested that working memory played a key role in this activity, assuming people solve problems by mentally restructuring the problem information. By contrast, the theoretical framework provided by distributed cognition suggests a complex co-occurrence between the problem solvers internal cognitive processes and their immediate environment (Kirsh, 2009). Cognition may be distributed across three dimensions: across the mind and its physical environment, through time where earlier events alter later events, and across members of social groups (Hollan, Hutchins & Kirsh, 2000).

When a problem solver is presented with a physical representation of a task, interacting with a physical representation, even with arbitrary moves, may offer cues to new strategies, enable better planning and increase efficiency in progressing towards a goal. Accordingly, when problem solvers are able to interact and restructure their environment, their ability to solve problems should be enhanced. Time distribution is also important and may impact upon problem solving performance, where previously learnt solutions may foster directed behavior towards a goal (e.g., Fioratou, Flin & Galvin, 2010).

So far, we found that increasing the interactivity of problem solvers’ immediate environment can facilitate insight as did incubation. Perhaps surprisingly, the highest proportion of insightful answers was observed when interactivity levels increased after incubation. This shows that insight depends not only on problem solvers’ internal resources but also on the features of the immediate environment, as anticipated by the distributed cognition framework.


Fioratou, E., Flin, R., & Glavin. (2010). No simple fix for fixation errors: Cognitive processes and their clinical applications. Journal of the Associations of Anaesthetists of Great Britain and Ireland, 65, 61-69.

Hollan, J., Hutchins, E., & Kirsh, D. (2000). Distributed cognition: Toward a new foundation for human-computer interaction research. ACM Transactions on Computer-Human Interactions, 7(2), 174-196.

Kirsh, D. (2009). Interaction, external representation and sense making. In N. A. Taatgen, & H. v. Rijn (Ed.), Proceedings of the Thirty First Annual Conference of the Cognitive Science Society (pp. 1103-1108). Austin, TX: Cognitive Science Society.

Newell, A., & Simon, H. A. (1972). Human problem solving. Engelwood Ciffs, NJ: Prentice-Hall.
Ohlsson, S. (2011). Deep learning: How the mind overrides experience. New York: Cambridge University Press.

Weller, A., Villejoubert, G., & Vallée-Tourangeau, F. (2011). Interactive Insight Problem Solving. Thinking & Reasoning, 17, 424–439. doi:10.1080/13546783.2011.629081

Career decisions over the increasing lifespan

This project aims to explore the circumstances and evolving preferences and perspectives which influence career decision-making processes over the growing lifespan.

For more than a century career guidance has aimed to match people normatively to jobs early in their careers. Career development patterns were depicted as largely pre-determined, mirroring an individual’s social background and psychological development stages (Super, 1980; Levinson, 1978) and fitting a prescribed path for organisational advancement following a timetable or script. In response to this deterministic view of careers, ‘new careers’ were proposed in the 1990s in which individuals managed their own career development (Hall, 1996; Arthur, 1994).

Issues and Impact:

In the 21st century the socio-economic environment is changing rapidly making career patterns less predictable, whilst increasing longevity and declining pension provision are combining to put pressure on anticipated career trajectories and retirement financing across the developed economies. Early career decisions need to be revisited at a later stage when individual criteria may be very different according to research suggesting that career and personal preferences and influences change over time (Erikson, 1959; Kooij et al., 2011).

An alternative perspective is therefore to explore career decision-making processes at different career stages in the light of theories about decision-making processes from the disciplines of Marketing and Psychology and calls have already been made for the decision-making perspective to be taken into account in studying aspects of career development over time (Demerouti, Peeters and van der Heijden, 2012).


Career decision-making processes at two different career stages will be explored through cognitive interviews and thematic analysis of the interview transcripts supported by documentary evidence from resumes and other sources.


Arthur, M. (1994). The Boundaryless Career: A New Perspective for Organisational Inquiry. Journal of Organizational Behavior, 15(4,) pp. 295-306.

Demerouti, E., Peeters, M.C.W., van der Heijden, B.I.J.M. (2012). Work–family interface from a life and career stage perspective: The role of demands and resources. International Journal of Psychology 47, pp. 241–258.

Erikson, E.H., (1959). Identity and the life cycle: Selected papers. Psychological Issues 1, pp. 1–171.

Hall, D. 1996. Protean Careers of the 21st Century. The Academy of Management Executive, 10(4), pp.  8-16.

Kooij, D. (2011). Age and work-related motives: Results of a meta-analysis. Journal of Organizational  Behavior 32(2),  pp. 197-225

Levinson, D. 1986. A Conception of Adult Development. American Psychologist, 41(1), pp. 3-13.

Super, D.E., 1980. A life-span, life-space approach to career development. Journal of Vocational Behavior 16, pp. 282–298.