While it is possible to describe network data as just a special form of conventional data (and it
is), network analysts look at the data in some rather fundamentally different ways. Rather than
thinking about how an actor's ties with other actors describes the attributes of "ego," network
analysts instead see a structure of connections, within which the actor is embedded. Actors
are described by their relations, not by their attributes. And, the relations themselves are just
as fundamental as the actors that they connect.
The major difference between conventional and network data is that conventional data focuses
on actors and attributes; network data focus on actors and relations. The difference in
emphasis is consequential for the choices that a researcher must make in deciding on
research design, in conducting sampling, developing measurement, and handling the resulting
data. It is not that the research tools used by network analysts are different from those of other
social scientists (they mostly are not). But the special purposes and emphases of network
research do call for some different considerations.
In this chapter, we will take a look at some of the issues that arise in design, sampling, and
measurement for social network analysis. Our discussion will focus on the two parts of network
data: nodes (or actors) and edges (or relations). We will try to show some of the ways in which
network data are similar to, and different from more familar actor by attribute data. We will
introduce some new terminology that makes it easier to describe the special features of
network data. Lastly, we will briefly discuss how the differences between network and actorattribute
data are consequential for the application of statistical tools