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UPLOAD YOUR DATA MATRIX


PASTE YOUR MATRIX HERE...  (  )





...OR UPLOAD A TEXT FILE...  
(  )





...OR COMPUTE NESTEDNESS OF A RANDOMLY GENERATED MATRIX  
(  )

Define Random Matrix:

Matrix Size (i.e. number of rows and columns): 
Degree of nestedness (0-9): 






IGNORE EMPTY ROWS AND COLUMNS  
(  )




DO NOT PACK THE MATRIX   
(  )





SELECT A NESTEDNESS METRIC:

NODF
MT
BR
Spectral Radius*




GENERATE NULL MATRICES TO COMPUTE Z VALUES AND RELATIVE NESTEDNESS   
(  )

Matrix Rearrangement Rules

Equiprobable row and column totals (EE)
Proportional row and column totals (CE)
Equiprobable row totals, fixed column totals (EF)
Fixed row totals, equiprobable column totals (FE)
Fixed column and row totals based on Curveball Algorithm (FF)**
Shuffled columns (SC)***
Shuffled rows (SR)***


Number of Null Matrices:  





*Staniczenko et al. 2013. The ghost of nestedness in ecological networks. Nature Communications 4,1391, doi:10.1038/ncomms2422.

**Strona et al. 2014. A fast and unbiased procedure to randomize ecological binary matrices with fixed row and column totals. Nature communications 5, 4114, doi:10.1038/ncomms5114.

***The SC and SR null models randomize, respectively, the order of columns and the order of rows in the matrix. These null models should be used in combination with NODF with the option DO NOT PACK THE MATRIX, in order to test if a particular ordering of the matrix (based, for example, on area size) leads to a higher degree of nestedness than expected by chance. If you select one of these two null models, the option DO NOT PACK THE MATRIX will be automatically selected, and NODF will be used as the only nestedness measure.

© Giovanni Strona & Simone Fattorini 2014

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