Tag Archives: University of Luxembourg

Art appraised by algorithm

Artificial intelligence has been introduced to art appraisals and auctions by way of an academic research project. A January 27, 2022 University of Luxembourg press release (also on EurekAlert but published February 2, 2022) announces the research, Note: Links have been removed,

Does artificial intelligence have a place in such a fickle and quirky environment as the secondary art market? Can an algorithm learn to predict the value assigned to an artwork at auction?

These questions, among others, were analysed by a group of researchers including Roman Kräussl, professor at the Department of Finance at the University of Luxembourg and co-authors Mathieu Aubry (École des Ponts ParisTech), Gustavo Manso (Haas School of Business, University of California at Berkeley), and Christophe Spaenjers (HEC Paris). The resulting paper, Biased Auctioneers, has been accepted for publication in the top-ranked Journal of Finance.

Training a neural network to appraise art 

In this study, which combines fields of finance and computer science, researchers used machine learning and artificial intelligence to create a neural network algorithm that mimics the work of human appraisers by generating price predictions for art at auction. This algorithm relies on data using both visual and non-visual characteristics of artwork. The authors of this study unleashed their algorithm on a vast set of art sales data capturing 1.2 million painting auctions from 2008 to 2014, training the neural network with both an image of the artwork, and information such as the artist, the medium and the auction house where the work was sold. Once trained to this dataset, the authors asked the neural network to predict the auction house pre-sale estimates, ‘buy-in’ price (the minimum price at which the work will be sold), as well as the final auction price for art sales in the year 2015. It became then possible to compare the algorithm’s estimate with the real-word data, and determine whether the relative level of the machine-generated price predictions predicts relative price outcomes.

The path towards a more efficient market?

Not too surprisingly, the human experts’ predications [sic] were more accurate than the algorithm, whose prediction, in turn, was more accurate than the standard linear hedonic model which researchers used to benchmark the study. Reasons for the discrepancy between human and machine include, as the authors argue, mainly access to a larger amount of information about the individual works of art including provenance, condition and historical context. Although interesting, the authors’ goal was not to pit human against machine on this specific task. On the contrary, the authors aimed at discovering the usefulness and potential applications of machine-based valuations. For example, using such an algorithm, it may be possible to determine whether an auctioneer’s pre-sale valuations are too pessimistic or too optimistic, effectively predicting the prediction errors of the auctioneers. Ultimately, this information could be used to correct for these kinds of man-made market inefficiencies.

Beyond the auction block

The implications of this methodology and the applied computational power, however, is not limited to the art world. Other markets trading in ‘real’ assets, which rely heavily on human appraisers, namely the real estate market, can benefit from the research. While AI is not likely to replace humans just yet, machine-learning technology as demonstrated by the researchers may become an important tool for investors and intermediaries, who wish to gain access to as much information, as quickly and as cheaply as possible.

Here’s a link to and a citation for the paper,

Biased Auctioneers by Mathieu Aubry, Roman Kräussl, Gustavo Manso, and Christophe Spaenjers. Journal of Finance, Forthcoming [print issue], Available at SSRN: https://ssrn.com/abstract=3347175 or http://dx.doi.org/10.2139/ssrn.3347175 Published online: January 6, 2022

This paper appears to be open access online and was last revised on January 13, 2022.

Artificial graphene?

I’m not sure I ever want to hear the word ‘revolutionary’ or its cousin’ revolution’ in relationship to science and/or technology ever again and I don’t think anyone’s going to be paying attention to this heartfelt plea: please, please, please find another word for a couple of years at least.  That said, artificial graphene does sound exciting as it’s described in a Feb. 17, 2014 news item on Azonano,

A new breed of ultra thin super-material has the potential to cause a technological revolution. “Artificial graphene” should lead to faster, smaller and lighter electronic and optical devices of all kinds, including higher performance photovoltaic cells, lasers or LED lighting.

For the first time, scientists are able to produce and have analysed artificial graphene from traditional semiconductor materials. Such is the scientific importance of this breakthrough these findings were published recently in one of the world’s leading physics journals, Physical Review X. A researcher from the University of Luxembourg played an important role in this highly innovative work.

The University of Luxembourg Feb. 14, 2014 news release (also on EurekAlert), which originated the news item, describes both graphene and artificial graphene

Graphene (derived from graphite) is a one atom thick honeycomb lattice of carbon atoms. This strong, flexible, conducting and transparent material has huge scientific and technological potential. Only discovered in 2004, there is a major global push to understand its potential uses. Artificial graphene has the same honeycomb structure, but in this case, instead of carbon atoms, nanometer-thick semiconductor crystals are used. Changing the size, shape and chemical nature of the nano-crystals, makes it possible to tailor the material to each specific task.

University of Luxembourg researcher Dr. Efterpi Kalesaki from the Physics and Materials Science Research Unit is the first author of the article appearing in the Physical Review X . Dr. Kalesaki said: “these self‐assembled semi-conducting nano-crystals with a honeycomb structure are emerging as a new class of systems with great potential.” Prof Ludger Wirtz, head of the Theoretical Solid-State Physics group at the University of Luxembourg, added: “artificial graphene opens the door to a wide variety of materials with variable nano‐geometry and ‘tunable’ properties.”

I’m going to provide two links and two citations to the paper as its publishing journal is currently beta testing a new website and the paper is available on both,

Dirac Cones, Topological Edge States, and Nontrivial Flat Bands in Two-Dimensional Semiconductors with a Honeycomb Nanogeometry by E. Kalesaki, C. Delerue, C. Morais Smith, W. Beugeling, G. Allan, and D. Vanmaekelbergh. Phys. Rev. X 4, 011010 (2014) [12 pages] DOI: 10.1103/PhysRevX.4.011010

Dirac Cones, Topological Edge States, and Nontrivial Flat Bands in Two-Dimensional Semiconductors with a Honeycomb Nanogeometry by E. Kalesaki, C. Delerue, C. Morais Smith, W. Beugeling, G. Allan, and D. Vanmaekelbergh. Phys. Rev. X 4, 011010 – Published 30 January 2014 DOI: http://dx.doi.org/10.1103/PhysRevX.4.011010

The second link to the paper will take you to the journal’s beta site. I have to give the designers a big thumbs up on the new design. To contextualize my review, I’m not a fan of changing website designs as functionality is too often sacrificed for ‘good looks’. Sadly, I do have a bit more work cutting and pasting with the new version but I’m hugely relieved that I did not have to spend several minutes trying to find the information.

Both versions of the paper are open access.