Comparing multi-level modeling approaches

As the range of modelling approaches that claim to be “multi-level” diversifies, there is growing debate in the literature about what multi-level modelling actually is and what form supporting languages and infrastructures should take. However, there is no consensus yet on how this debate should be framed and what objective criteria should be used to evaluate different approaches. It is clear from the literature that proponents of different approaches base their arguments on fundamentally different assumptions about what multi-level modelling is and what benefits it should aim to provide. In this position paper we identify some of the core issues that currently hinder progress towards the required consensus and identify some of the terminological differences that have amplified confusion. Referencing various work that represents diverging viewpoints, our goal is to initiate a meta-discussion on what the open questions in multi-level modelling are, how respective proposals to answer them could be evaluated, and which kinds of discussions are expedient in this context.