Reply and gridstat method to calculate euclidean distances:

bob green (bgreen@dyson.brisnet.org.au)
Wed, 16 Jun 1999 21:50:19 +1000

Richard,

I think I managed to get your 1984 paper, so I will check it out.

>I was thinking of a paper I gave at the Australian PCP conference in 1984
>(hardly new stuff!) where I used the ability of some multidimensional
>scaling programs to 'fix' the location of some points and estimate the
>rest. Run an mds at time 1 (say). At time 2 'fix' the locations of the
>common elements/constructs, and estimate the locations of the other time 2
>elements/constructs. Put the two solutions in the same picture. The common
>ones will be in the same positions, and you should be able to see how the
>time 1 unique constructs/elements relate to the time 2 unique ones.
>Other possibilities:

Would another option be to run both grids in an ALSCAl analysis?

Regarding calculating Euclidean distances between elements, could I do this by:

1. squaring the difference between the ratings on each construct and summing the
results.

2. Take the square root of the sum.

regards,

Bob

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