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# 3: Using Graphs to Represent Social Relations

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• 3.1: Introduction - Representing networks with graphs
Social network analysts use two kinds of tools from mathematics to represent information about patterns of ties among social actors: graphs and matrices. On this page, we we will learn enough about graphs to understand how to represent social network data. On the next page, we will look at matrix representations of social relations. With these tools in hand, we can understand most of the things that network analysts do with such data (e.g., calculate precise measures of "relative density").
• 3.2: Graphs and Sociograms
There are lots of different kinds of "graphs." Bar-charts, pie-charts, line and trend charts, and many other things are called graphs and/or graphics. Network analysis uses (primarily) one kind of graphic display that consists of points (or nodes) to represent actors and lines (or edges) to represent ties or relations. When sociologists borrowed this way of graphing things from the mathematicians, they re-named their graphics "socio-grams."
• 3.3: Kinds of Graphs
Now we need to introduce some terminology to describe different kinds of graphs.
• 3.4: Summary
• 3.E: Using graphs to represent social relations (Exercises)