# The isomorphic version of Brualdies nestedness is in P

```@inproceedings{Berger2016TheIV,
title={The isomorphic version of Brualdies nestedness is in P},
author={Annabell Berger},
year={2016}
}```
• A. Berger
• Published 8 February 2016
• Mathematics
The discrepancy BR for an m × n 0, 1-matrix from Brualdi and Sanderson 1998 counts the minimum number of 1’s which need to be shifted in each row to the left to achieve its Ferrers matrix, i.e. each row consists of consecutive 1’s followed by consecutive 0’s. For ecological bipartite networks BR describes how nested a set of relationships is. Since different labeled matrices can be isomorphic but possess different discrepancies, we define a metric determining the minimum discrepancy in an…
2 Citations
Let m and n be positive integers, and let R = (r1, . . . , rm) and S = (s1, . . . , sn) be nonnegative integral vectors. Let A(R,S) be the set of all m × n (0, 1)-matrices with row sum vector R and
This paper presents a method based on the similarity of rows and columns, which uses correlation clustering to cluster the rows and Columns of the matrix, facilitating the visualization of the relation by rearranging therows and columns.

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