MCSN Thursday, 15-Sep-11
Contents
Today's assignment
Read sections 1.3.3 to 1.5; submit 1.6; come to class prepared with a Pajek example drawn from the Web, and illustrating chapter content. This will be a regular Thursday assignment. This week, the ESNAP readings focussed on a directed graph, so any directed graph from the web is fine. For instance, you could extract a portion of Twitter.com "following" relations, or look at musician relations (influences, influenced by) on allmusic.com. The point is to create a directed graph in Pajek.
Question of the day
- Definition: Combinatorics: counting the number of structures with particular properties. (e.g. the number of different connected, undirected, simple graphs on 4 vertices)
- Definition: "Different": non-isomorphic
- Here, "different" means "non-isomorphic".
- Isomorphic graphs contain the same connection information
- E.g.: a square and a trapazoid and a twisted square graph are all isomorphic
- Energizing graphs in Pajek always generates an isomorphic equivalent
- Question: What is the relevance of graph combinatorics to the cross-cultural study of musical groups? What might be revealed by an investigate of the relation between non-isomorphic graph types, and the dynamics of performance?
Brainstorming continues...
- More precipitation from your brainstorms
Homework exercises from Tuesday - review
Nuts-and-bolts: how to create networks in Pajek
- Creating and manipulating networks in Pajek itself
- Editing Pajek files in a text processor
- Edge and arc list formats
- Matrix format
- Using txt2pajek
- Using a programming language (e.g. scripting language such as php, perl, etc.) to generate Pajek files
