This year, there were twenty-nine nominations for the KNVI/KIVI Thesis Awards. All candidates received very good reviews for their theses at their respective universities.

The jury was very impressed by the quality of the theses. This high quality did not make things easy for the jury. The judging was done in two rounds, with a top seven being selected in the first round.

1st prize: Z. (Zhaiyu) Chen MSc, TU Delft
Learning to Reconstruct Compact Building Models from Point Clouds
The first prize goes to Zhaiyu Chen for his thesis entitled "Learning to Reconstruct Compact Building Models from Point Clouds." His work forms part of a branch of Data Science called Geomatics that essentially focuses on the gathering, processing and analyses of geographic data and information. The title of the work is the shortest possible summary of a very difficult problem. Imagine you have a digital photo of a building. As you may know, such photos are built from pixels: a huge collection of colourful dots. Together, those dots seem to form objects. The human brain is imaginative enough to see, for example, a building. Computers are not imaginative. In fact they are not even capable of representing a collection of dots that for us obviously form a wall with perhaps a window in it, to a representation stating "this is a wall with a window in it". What Zhaiyu has done is develop a means for computers to transform collections of dots (called point clouds) that form a 3D photo of a building, to a representation of such a building to a collection of shapes (such as rectangles). The result is not only a much more natural representation, but also one that can easily be viewed from different angles as we can experience with 3D representations of designs for a house. The approach that Zhaiyu has followed is literally learning computers to make this transformation, through an advanced technique from artificial intelligence called deep learning. To make this work for very different types of point clouds is a huge challenge. The overall result is downright impressive, and the jury was unanimous in their decision that this was top-notch research and exceptionally well explained in the thesis.

Shared 2nd prize: M.D. (Maaike) Los MSc, University of Groningen
Choosing Fair Committees and Budgets:
Proportionality in Multi-Winner Elections and Participatory Budgeting

The second prize goes to Maaike Los. Maaike has written a thesis on the mathematical aspects of voting on a particular issue by more than one party, such as choosing a committee or allocating money to projects. To give an example of this: A municipality has a certain budget for projects and wants citizens to vote on the order of allocation of these projects. Important aspects here are fairness and proportionality. With the latter, one can think of that all citizens' groups are given equal consideration.
Maaike's contribution is twofold. First, she gives a mathematical analysis of existing algorithms in this field and comes up with new, often non-trivial results. For algorithms where an analysis could not be achieved, she has performed some well-considered experiments on a synthetic dataset. With this combination of theory and experiment, she has made an important contribution to the systematisation of proportionality axioms for committee selection and participatory budget allocation. The thesis report is crisply written. All these things together impressed the jury, which unanimously nominated her for the prize.

Shared 2nd prize: D. (Dominik) Wehr MSc, University of Amsterdam
An Abstract Framework for the Analysis of Cyclic Derivations
The other second prize goes to the thesis "An Abstract Framework for the Analysis of Cyclic Derivations" by Dominik Wehr obtained at the University of Amsterdam. This thesis is in theoretical computer science and makes an impressive step towards the better understanding of so-called cyclic proofs. Cyclic proofs are finite graphs representing infinite mathematical proofs and are instrumental to reason about such infinite proofs. They are used to establish the correctness of computer programs manipulating recursive data types such as lists and trees. A program is correct if it does what it is supposed to do and does not suffer from anomalies such as ending up in an endless loop without making progress. Cyclic proofs are also used in mathematical logics that include some form of recursion. The diversity of existing cyclic proof systems raises the question: what are their commonalities and what are their distinctive ingredients? This thesis presents an abstract framework that is an important step in answering these questions. The jury was impressed by the deep technical results in the thesis and the broad spectrum of non-trivial techniques - such as automata theory, category theory and mathematical logic - that are used by Dominik Wehr to establish his results.

Nine incentive prizes were also awarded:

Bozhidar Andonov TUD
Henk Berendsen RU
Thierry Blankenstein UvA
Channa Dias Perera RUG
Silas de Graaf UT
Zsófia Katona VU
Joost van der Laan UU
Nidhish Shah TUE
Lieke Vertegaal UL