behavioural change

Kristina M. Persson´s thesis consists of three articles that investigate changes in human behaviour as a result of changes in incentives.
PhD Defense

22 August 2017 12:14

behavioural change

On Thursday 31 August 2017 Kristina Maria Persson will hold a trial lecture on a prescribed topic and defend her thesis for the PhD degree at NHH.

Prescribed topic for the trial lecture:

 Tax evasion: theory, evidence, and policy recommendations

Trial lecture:

10:15 in Jebsen Centre, NHH

PhD Candidate Kristina Maria Persson.
PhD Candidate Kristina Maria Persson, Department of Economics, NHH.

Title of the thesis:

Essays on behavioural change


The thesis consists of three articles that investigate changes in human behaviour as a result of changes in incentives. The methodological approaches to studying the behavioural changes vary in each of the articles, attempting to appropriately address each research question and the available data. 

The first article “Differential effects of gender-specific labour demand shocks on fertility and outcomes for children” is co-authored by Kari Vea Salvanes. The authors combine large Norwegian registry datasets over a 50-year period in order to analyse when and how children are born along business cycles. Over the period 1990 – 2009, the authors find that fertility rates are negatively correlated with business cycles, and there are no health effects of children at birth. Lastly, the authors find that results for child health are sensitive to aggregation levels of data, cautioning the robustness of the current and previous studies.

The second article “You’ve got mail – a randomised field experiment on tax evasion” describes a randomised field experiment in collaboration with the Norwegian Tax Administration (NTA), which is joint work by Alexander W. Cappelen, Erik Ø. Sørensen and Bertil Tungodden. The authors find that moral motivations play an important role in increasing tax compliance. Interestingly, while moral appeals increase the amounts of self-declarations, more people report positive amounts when having updated perceived detection probabilities. This insight is important both for policymakers thinking about tax avoidance but also more broadly. 

The third article “Increasing tax compliance – auditing, appeals to tax morale, or both?” presents a laboratory (lab) experiment. The author addresses a follow-up question from the second article, if it is beneficial to combine moral appeals and information about audit probabilities in communications with taxpayers. The positive effects of both measures may be additive, cancel each other out, or the presence of audit information crowds out intrinsic motivations to comply. A lab experiment is particularly suited to address this question since it is possible to control for beliefs about audit probabilities by fixing them at objective probabilities. The author finds that moral appeals in the form of social information about a reference group play an important role, if the taxpayer identifies with the reference group. No evidence of an interaction effect can be found, suggesting that it is safe for institutions to combine moral appeals and information about audit probabilities. A combination is likely to increase the reach of taxpayers and increase self-declarations.


12:15 in Jebsen Centre, NHH

Members of the evaluation committee:

Professor Kjetil Bjorvatn (leader of the committee), Department of Economics, NHH

Professor Nadja Dwenger, Uni Hohenheim

Professor Bjørn Bartling, University of Zurich and NHH


Professor Erik Ø. Sørensen (main supervisor), Department of Economics, NHH

Professor Kjell Gunnar Salvanes, Department of Economics, NHH

The trial lecture and thesis defence will be open to the public. Copies of the thesis will be available from                       

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