9 citations · 27 across the 6 of their papers we have counts for
6 papers
Tracking Behavioral Patterns among Students in an Online Educational System
Stephan Lorenzen, Niklas Hjuler, Stephen Alstrup
Analysis of log data generated by online educational systems is an essential task to better the educational systems and increase our understanding of how students learn. In this st…
Investigating Writing Style Development in High School
Stephan Lorenzen, Niklas Hjuler, Stephen Alstrup
In this paper we do the first large scale analysis of writing style development among Danish high school students. More than 10K students with more than 100K essays are analyzed. W…
Detecting Ghostwriters in High Schools
Magnus Stavngaard, August Sørensen, Stephan Lorenzen +2
Students hiring ghostwriters to write their assignments is an increasing problem in educational institutions all over the world, with companies selling these services as a product.…
Dominating Sets and Connected Dominating Sets in Dynamic Graphs
Niklas Hjuler, Giuseppe F. Italiano, Nikos Parotsidis +1
In this paper we study the dynamic versions of two basic graph problems: Minimum Dominating Set and its variant Minimum Connected Dominating Set. For those two problems, we present…
One-Way Trail Orientations
Anders Aamand, Niklas Hjuler, Jacob Holm +1
Given a graph, does there exist an orientation of the edges such that the resulting directed graph is strongly connected? Robbins' theorem [Robbins, Am. Math. Monthly, 1939] states…
Sequence Modelling For Analysing Student Interaction with Educational Systems
Christian Hansen, Casper Hansen, Niklas Hjuler +2
The analysis of log data generated by online educational systems is an important task for improving the systems, and furthering our knowledge of how students learn. This paper uses…