Netters:
Several weeks ago I posted a request for information on the availability
of programs for doing non-metric multidimensional scaling (NMDS) of large
data matrices. I have limited the information below to programs
specifically designed for analysis of ecological data. You will see that I
have included only basic information about the software - I *strongly*
suggest you contact the authors for more recent information and pricing.
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Program: SYNTAX
Version: 5.0
System: DOS and MAC
Author: Janos Podani
Address: Department of Plant Taxonomy and Ecology
L. Eotvos University
Budapest, Hungary
internet: podani at ludens.elte.hu
Comments: SYNTAX is an integrated set of ecological data analysis programs
which includes clustering, ordination (including NMDS), matrix editing and
transformations, and spatial analysis. NMDS is limited to 99 samples but
unlimited to number of species. Price as of 12/92 was US$ 150 for personal
use - contact the author for current price.
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Program: PC-ORD
Version: ?
System: DOS
Author: Bruce McCune
Address: Department of Botany and Plant Pathology
Oregon State University
Corvallis, Oregon 97331-2902
internet: mccuneb at bcc.orst.edu
Comments: PC-ORD includes programs for PCA, TWINSPAN, cluster analysis,
DECORANA and NMDS. NMDS can be done on matrices of up to 200 samples x 200
species. Current price is US$ 50.
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Program: DECODA
Version: ?
System: DOS and mainframe
Author: Peter Minchin
Address: Department of Botany
University of Melbourne
Melbourne, Victoria, Australia
internet: minchin at botany.unimelb.edu.au
Comments: DECODA includes programs for NMDS, DECORANA, TWINSPAN and a
number of routines for interpreting species - environment relationships.
It also has data editing and transformation capabilities. In the DOS
version, the NMDS module can analyse 500 species and 200 samples; the
mainframe version can handle considerably larger datasets. Current price
is AUST$ 515 (US$ ??).
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Program: NTSYS-PC
Version: 1.6 (as of 1991)
System: DOS
Author: Applied Biostatistics Inc.
Address: Order from Exeter Software
100 North Country Road, Building B
Setauket, New York 11733
Comments: The program can do calculation of similarity/dissimilarity
matrices, several types of clustering, minimum spanning trees and
ordination (PCA, PCO, CA, NMDS). No information was given about maximum
data file size. Price as of 1991 was US$ 140 for educational institutions
and $175 for individuals (no doubt this is out of date).
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Program: NMDS module included with text book "Statistical Ecology", by
Ludwig and Reynolds, 1988.
Version: ?
System: DOS and MAC
Author: J.A. Ludwig and J.F. Reynolds
Address: Book and program available from John Wiley & Sons, New York.
Comments: The NMDS program is one of 21 programs included with the book.
Each is designed to be used with one of the book chapters; the programs
are fairly slow and not meant to be used for analysis of large data sets.
However, the book and programs form an excellent introduction to many
aspects of quantitative ecology and are good for teaching (only my humble
opinion).
Many commercial statistics programs also do NMDS - SAS, BMDP, SPSS, SYSTAT
and Statistica, to name a few. I have not investigated the capabilities of
these programs. I would like to hear from those of you that have used any
of these programs for NMDS. Please keep the net informed of any additional
developments in this area.
Mark Johnston
mjohnst at cs_acad_lan.lakeheadu.ca
