Quality & Quantity (2005) 39: 241–251 © Springer 2005
Representation of Developments in Labour
Department of Sociology, Groningen University, NL 9712 TG 31, Groningen,
The Netherlands. E-mail: email@example.com
Abstract. A knowledge graph is a kind of semantic network representing some scientiﬁc the-
ory. The paper describes the state of art in this ﬁeld and addresses a number of problems
that has not been solved yet. These are: implicit relations, strength of (causal) relations, and
conditions. Concepts might be too broad or complex to be used properly, directions for solv-
ing this problem are explored. The solutions are applied to a knowledge graph in the ﬁeld
of labour markets.
Key words: knowledge graphs, knowledge representation
For some years labour markets have been a relevant research issue in the
program of the research school Inter University Center for Social Science
(ICS). Based on results empirical found in the ﬁrst six Ph.D.-theses of stu-
dents of this school and on interviews with these students Popping and
Strijker (1997) wanted to present the state of art in the ﬁeld of labour
markets. The theses however were on different aspects of labour markets.
Therefore the network contained several groups of points connected by few
relations. This was an unsatisfying. Therefore the (not empirically tested)
theory on labour markets was presented. This theory was presented in a
network structure. The concepts were represented as labelled points, and
relations between concepts as typed links between the points. Such net-
works are known as knowledge graphs.
Still it remains relevant to show the network based on empirical ﬁnd-
ings. Only this makes it possible to show growth in later stages when the
network is based on more ﬁndings. In this text the empirical network is
presented and related to the theoretical one.
2. Labour Markets
The choice for sociological theories about labour markets as knowledge
domain is a pragmatic one. The Interuniversity Center for Social Sciences