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**CENTRALITY>GROUP > CENTRALITY > OPTIMIZE **

**PURPOSE **Find a group with a specified size with the highest group degree centrality.

**DESCRIPTION** The group degree centrality of a group of actors is the size of the set of actors who are directly connected to group members. This routine uses a simple greedy algorithm to optimize this measure for a fixed size group. Local minima are avoided by taking a number of different random starting configurations.

**PARAMETERS**

**Input dataset:**

** **Name of file containing network to be analyzed. Data type: Graph.

**Desired Group Size** (Default = 10).

Specified size of group.

**No. of starts: **(Default = 100)

Number of random starts used to avoid local minima

** Output dataset:** ('BestDegGroup')

Name of UCINET dataset containing a group indicator vector. The rows give the actors and an actor is in the group with the largest group degree centrality if the entry in the vector is a 1. This vector is not shown in the LOGFILE.

**LOG FILE** The fit is the percentage of actors (both within and outside) adjacent to group members. The starting fit, final fit and the number of actors together with the final number of actors connected to the group are reported. This is followed by a list of the members of the group with the highest group degree centrality.

**TIMING **O(N^2).

**COMMENTS **Note that this routine just finds one group. There could be many others.

**REFERENCE **Everett, M.G. and Borgatti, S.P. (1999) The Centrality of Groups and Classes. Journal of Mathematical Sociology 23 181-202.