Diederik Stapel


Diederik Alexander Stapel is a Dutch former professor of social psychology at Tilburg University. In 2011 Tilburg University suspended Stapel for fabricating and manipulating data for his research publications. This scientific misconduct took place over a number of years and affected dozens of his publications., Stapel has had 58 of these publications retracted.

Early life

Stapel was born to Rob Stapel and Dirkje Stapel on 19 October 1966 in the village of Oegstgeest, near Leiden.
In high school, he met his would-be wife Marcelle, whom he later married in 1997. After completing his schooling, Stapel, for a while, studied acting at East Stroudsburg University in Pennsylvania before moving back to the Netherlands for an undergraduate degree in Psychology.

Career

Stapel obtained an M.A. in psychology and communications in 1991 and a Ph.D. cum laude in social psychology in 1997, all from the University of Amsterdam. He became a professor at the University of Groningen in 2000 and moved to Tilburg University in 2006, where he founded TiBER, the Tilburg Institute for Behavioral Economics Research. In September 2010, Stapel became dean of the social and behavioral sciences faculty.
Stapel received the Career Trajectory Award from the Society of Experimental Social Psychology in 2009, which has since been retracted. He returned his Ph.D. title to the University of Amsterdam in November 2011, noting that his "behavior of the past years are inconsistent with the duties associated with the doctorate".
In October 2014, Dutch media reported that Stapel had returned to work, teaching social philosophy at the Fontys Academy for Creative Industries in Tilburg.

Scientific misconduct

In September 2011, Tilburg University suspended Stapel due to his fabrication of data used in research publications. The university announced an investigation of his work.

Levelt committee

On 31 October 2011, a committee entrusted with investigating "the extent and nature of the breach of scientific integrity committed by Mr D.A. Stapel", formed by the Rector Magnificus of Tilburg University and chaired by Willem Levelt, published an interim report regarding Stapel's activities at the three Dutch universities where he had worked. The interim report pointed to three unidentified young researchers as the whistleblowers for the case, and implies that these whistleblowers spent months making observations of Stapel and his work before they concluded that something actually was wrong.
The report also cites two professors who claim they had previously seen examples of Stapel's data that were "too good to be true." The report concluded that Stapel made up data for at least 30 publications.
His general method towards the end of his career was to develop a complete experiment at the level of theory, hypotheses, methods, stimuli, questionnaires, and even participants' rewards – and then pretend that he would run the experiments at schools to which only he had access. Instead of doing so, he would make up the data and send these to colleagues for further analysis. The report also stated that earlier in his career, going back at least to 2004, he appears to have manipulated data rather than faked them.
In all cases he acted alone and the report did not find any indication that coauthors, PhD students, or others were aware even in instances where suspicion may have been reasonable. On pages six to seven, the interim report names 19 theses prepared with data delivered by Stapel. Of those, seven have been cleared. There are various degrees of suspicion about the remaining 12. The report advised that the degrees of the students involved should not be retracted.
It became widely known that Stapel treated his graduate students unfairly, with most of them graduating without ever actually completing an experiment.
Stapel controlled the data in his lab, and when students asked to see the raw data, they were often given excuses.
According to the report, there were occasions when Stapel's data were given to an assistant to be entered into a computer. This assistant would then return the data file to Stapel. The researcher analyzing the data would then receive the file directly from Stapel. Stapel would apparently tell this researcher to "Be aware that you have gold in your hands." The report also suggests that Stapel elected to present a list of publications that contained fictitious data.
The interim report stated that it was not possible to determine whether Stapel fabricated or manipulated data for his 1997 dissertation at the University of Amsterdam, because the data had been destroyed. The university announced that it would investigate whether it would be possible to retract Stapel's Ph.D. because of exceptionally unworthy scientific behavior.
The interim report stated that Stapel had caused severe damage to young people at the beginning of their careers, as well as to the general confidence in science, in particular social psychology. The University of Tilburg announced that it would pursue criminal prosecution of Stapel.
An extensive report investigates all of Stapel's 130 articles and 24 book chapters. A website was set up on 27 March 2012 to publish intermediate findings. According to the first findings, on the first batch of 20 publications by Stapel, studied by the Levelt committee, 12 were falsified and three contributions to books were also fraudulent. de Volkskrant reported that the final report was due on 28 November 2012, and that a book by Stapel was to be released around the same time.
"We have some 30 papers in peer-reviewed journals where we are actually sure that they are fake, and there are more to come," Pim Levelt, chair of the committee investigating Stapel's work stated.

Coping with chaos

A month after Tilburg University announced that it had found evidence of fraud in Stapel's work, the journal Science posted a retraction notice on Stapel's co-authored paper entitled Coping with chaos: How disordered contexts promote stereotyping and discrimination. The report from Science says:
In December 2011, Stapel retracted this paper, the first to be retracted. The journal expressed initial concern regarding the paper's validity on November 1. In a response to the retraction, coauthor of the Chaos paper Siegwart Lindenberg told the journal in an email, "Stapel's doing had caught me as much by surprise as it did anybody else. I never had any suspicion. He was a very trusted man, dean of the faculty, brilliant, successful, no indications for me to be distrustful. In this, I was not the only one. I also had no trouble with the results of the experiments."

Selfishness in carnivores

The research result, obtained by Stapel and co-workers Roos Vonk and Marcel Zeelenberg, that carnivores are more selfish than vegetarians, which was widely publicized in Dutch media, was suspected and later turned out to be based on falsified data. The research result had not yet been published in a scientific journal; only a press bulletin was released.

Reaction by Stapel

Responding to the interim report, Stapel stated:
In his memoirs published in November 2012, Stapel admits his fraud, but protests against the accusation in the interim report that he was a cunning, manipulative fraud with a plan.

Reaction in academia

On 28 November 2012, the joint final report, from the three investigating committees, was published.
It has been suggested that Stapel was able to continue his fraud for so long because of his status. At Tilburg he was "considered a star" and was seen by his colleagues and students as charismatic, friendly and incredibly talented. Many students became his personal friends. But the final Levelt report raises more controversial questions about the ways in which Stapel went unchallenged for so long. The report concludes that there was "a more general failure of scientific criticism in the peer community and a research culture that was excessively oriented to uncritical confirmation of one's own ideas and to finding appealing but theoretically superficial ad hoc results". It goes on to suggest that "not infrequently reviews were strongly in favour of telling an interesting, elegant, concise and compelling story, possibly at the expense of the necessary scientific diligence."
This aspect of the report has been criticised by the Social Psychology Section of the British Psychological Society. In a letter to the Times Higher Education Supplement, on behalf of the Section, Stephen Gibson at York St John University, points out ".. there are no grounds for concluding either that research fraud is any more common in social psychology than other disciplines or that its editorial processes are particularly poor at detecting it," adding that: "Our sub-discipline does not deserve the harm to its reputation that may be provoked by the careless implication of unique deficiencies." The Levelt report has also been criticised by the European Association of Social Psychology in an open letter to its members.
In the February 2013 issue of The Psychologist, Willem Levelt, together with the chairs of the other two investigating committees, published a rejoinder to these and other criticisms. Drenth et al. acknowledge that they did not compare the situation in social psychology with other disciplines, but note that "such a comparative investigation was not part of the Committees' commission."
In a review for the Association for Psychological Science, Stapel's 315-page memoirs, entitled Ontsporing, is described by Dutch psychologists Denny Borsboom and Eric-Jan Wagenmakers as "priceless and revealing." Stapel recounts that his misdemeanours began when he was sitting alone in his office and changed "an unexpected 2 into a 4". The reviewers describe the final chapter of the book as "unexpectedly beautiful" but note that it is full of lines taken from the works of writers Raymond Carver and James Joyce.

Prosecution settlement

In June 2013 Stapel agreed, in a settlement with the prosecutor, to perform 120 hours of community service and to lose the right to some benefits associated with his former job equivalent to a year and a half's worth of salary. In this way, he avoided further criminal prosecution.

List of withdrawn publications

As of December, 2015, Retraction Watch reported that Stapel had 58 retractions.
These include the following:
TitleYear of publicationJournalDOI and link to the retraction notice
Interpretation versus Reference Framing: Assimilation and Contrast Effects in the Organizational Domain1998Organizational Behavior and Human Decision Processes
Correction or comparison? The effects of prime awareness on social judgments2009European Journal of Social Psychology
The impact of comprehension versus self-enhancement goals on group perception2008Social Psychology
Measure by measure: When implicit and explicit social comparison effects differ2010Self and Identity
Unfinished business: How completeness affects the impact of emotional states and emotion concepts on social judgement2006Journal of Experimental Social Psychology
Hardly thinking about close and distant others: On cognitive business and target closeness in social comparison effects2005Journal of Experimental Social Psychology
The flexible unconscious: Investigating the judgmental impact of varieties of unaware perception2005Journal of Experimental Social Psychology
Distinctiveness is Key: How Different Types of Self-Other Similarity Moderate Social Comparison Effects2007Personality & Social Psychology Bulletin
Terror Management and Stereotyping: Why Do People Stereotype When Mortality Is Salient?2008Personality & Social Psychology Bulletin
When we wonder what it all means: Interpretation goals facilitate accessibility and stereotyping effects2001Personality & Social Psychology Bulletin
The effects of diffuse and distinct affect2002Journal of Personality and Social Psychology
Me tomorrow, the others later: How perspective fit increases sustainable behavior2010Journal of Environmental Psychology
Similarities and Differences between the Impact of Traits and Expectancies: What Matters Is Whether the Target Stimulus Is Ambiguous or Mixed2002Journal of Experimental Social Psychology
Information to go: Fluency enhances the usability of primed information2009Journal of Experimental Social Psychology
Distinguishing stereotype threat from priming effects: on the role of the social self and threat-based concerns2006Journal of Personality and Social Psychology
From seeing to being: subliminal social comparisons affect implicit and explicit self-evaluations2004Journal of Personality and Social Psychology
Method matters: effects of explicit versus implicit social comparisons on activation, behavior, and self-views2004Journal of Personality and Social Psychology
The magic spell of language: linguistic categories and their perceptual consequences2007Journal of Personality and Social Psychology
The self salience model of other-to-self effects: integrating principles of self-enhancement, complementarity, and imitation2006Journal of Personality and Social Psychology
Unconscious and spontaneous and...complex: the three selves model of social comparison assimilation and contrast2008Journal of Personality and Social Psychology
The Norm-Activating Power of Celebrity: The Dynamics of Success and Influence2011Social Psychology Quarterly
The downside of feeling better: Self-regard repair harms performance2008Self and Identity
Status concerns and financial debts in adolescents2010Social Influence
It's all in the timing: Measuring emotional reactions to stereotype threat before and after taking a test2006European Journal of Social Psychology
Making sense of war: using the interpretation comparison model to understand the Iraq conflict2006European Journal of Social Psychology
Staff, miter, book, share: how attributes of Saint Nicholas induce normative behavior2008European Journal of Social Psychology
Affects of the unexpected: when inconsistency feels good 2010Personality & Social Psychology Bulletin
Event Accessibility and Context Effects in Causal Inference: Judgment of a Different Order1996Personality & Social Psychology Bulletin
Silence and Table Manners: When Environments Activate Norms2008Personality & Social Psychology Bulletin
The influence of mood on attribution2010Personality & Social Psychology Bulletin
Why people stereotype affects how they stereotype: the differential influence of comprehension goals and self-enhancement goals on stereotyping2009Personality & Social Psychology Bulletin
Stop Making Sense: The Ultimate Fear2009Psychological Inquiry
Behavioural effects of automatic interpersonal versus intergroup social comparison2006British Journal of Social Psychology
How to heat up from the cold: examining the preconditions for mood effects2008Journal of Personality and Social Psychology
Mood and context-dependence: Positive mood increases and negative mood decreases the effects of context on perception2010Journal of Personality and Social Psychology
Moods as spotlights: the influence of mood on accessibility effects2008Journal of Personality and Social Psychology
No pain, no gain: the conditions under which upward comparisons lead to better performance2007Journal of Personality and Social Psychology
On models and vases: body dissatisfaction and proneness to social comparison effects2007Journal of Personality and Social Psychology
The referents of trait inferences: The impact of trait concepts versus actor–trait links on subsequent judgments1996Journal of Personality and Social Psychology
What drives self-affirmation effects? On the importance of differentiating value affirmation and attribute affirmation2011Journal of Personality and Social Psychology
Beauty as a tool: The effect of model attractiveness, product relevance, and elaboration likelihood on advertising effectiveness2010Psychology & Marketing
When different is better: Performance following upward comparison2006European Journal of Social Psychology
The unconscious unfolding of emotions2009European Review of Social Psychology
Emotion elicitor or emotion messenger? Subliminal priming reveals two faces of facial expressions2008Psychological Science
Judging the unexpected: Disconfirmation of situation-specific expectancies2009European Journal of Social Psychology
Racist biases in legal decisions are reduced by a justice focus2010European Journal of Social Psychology
The secret life of emotions2008Psychological Science
When nothing compares to me: How defensive motivations and similarity shape social comparison effects2006European Journal of Social Psychology
The Self-Activation Effect of Advertisements: Ads Can Affect Whether and How Consumers Think about the Self2010Journal of Consumer Research
It depends on how you look at it: being versus becoming mindsets determine responses to social comparisons2010British Journal of Social Psychology
The Effects of Different Types of Self–Activation on Social Comparison Orientation2006Social Cognition
The Mental Roots of System Justification: System Threat, Need for Structure, and Stereotyping2011Social Cognition
When failure feels better than success: Self-salience, self-consistency, and affect2011British Journal of Social Psychology
Stereotype Disconfirmation Affect: When Sweet Hooligans Make You Happy and Honest Salesmen Make You Sad2011Basic and Applied Social Psychology
What's in a Name? 361.708 Euros: The Effects of Marital Name Change2010Basic and Applied Social Psychology
Happiness as alchemy: Positive mood leads to self-serving responses to social comparisons2011Motivation and Emotion
Coping with Chaos: How Disordered Contexts Promote Stereotyping and Discrimination2011Science
From Perception to Emotion: A Global-to-Specific Unfolding View of Emotional Responding2010Emotion Regulation and Well-Being

Selected scientific publications