missing value handling & computational precision

From: Ian Martin (idmartin@golden.net)
Date: Wed Mar 30 2005 - 18:30:06 MEST

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    Hello/Bonjour -

    I have a question about ADE's handling of missing values in correlation
    PCA. Are missing values deleted pairwise in computation of the
    correlation matrix, or are means substituted? What is the default and
    is there facility to change this? I haven't been able to find this
    answer in the documentation pdfs, but perhaps I've not been looking in
    the correct place.

    Also, what is the computational precision of ADE-4 -- double precision
    (64-bit, real*8) or long precision (128-bit, real*16)?

    I'm trying to compare some PCA results to those obtained from SPSS.


    Ian D. Martin, Ph.D.
    Aquatic Ecologist

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