Ambrose et al. (2010, pp. 49-54) discussed the chain model, hierarchical model, and cross-referencing model of people’s knowledge organization. In these models, nodes are used to denote pieces of knowledge and undirected links are used to denote relationships among knowledge. These three models also can be used to describe many existing models of organizing knowledge on the Web for online learning (see Figure 1). In Figure 1, directed links are used to show the order of knowledge organization.
Existing models of organizing knowledge on the Web
An example of using an indexing model to organize knowledge on the Web (accessed July 8, 2021)
In a chain model (see Figure 1(1)), knowledge elements are arranged in the form of a chain, where directed links denote the order of arrangement. As an example of chain models, an indexing model in Figure 2 lists knowledge elements alphabetically. People can use an index list to quickly locate knowledge elements if they know the items to look for.
Indexing models are usually used for reference purposes. It assumes that people already know (or at least roughly know) the terms to look for, which is not the typical case in learning new knowledge. Hence, indexing models alone are not enough for learning new knowledge.