Hello,

I am new to R and I have a question about the difference between
correspondence analysis in R and SPSS.
This is the input table I am working with (4 products and 18 attributes):

> mytable
   1  2  3  4  5 6  7  8  9 10 11 12 13 14 15 16 17 18
1 15 11 20  4 14 7  1  2  1  4 12 12 17 19 11 20  9 10
2 19 18 14 14 16 4 14 11 11 15 22 19 22 16 21 19 15 16
3 16 13 10  9 15 4 10  7 11 13 18 17 14 14 16 16 13 11
4 21 18 16 14 20 6 12 14 14 17 23 20 19 18 21 18 19 18

I found the function corresp() in the package MASS, but the results are
different from the output in SPSS. Also, I don't understand the coordinates;
in the biplot I cannot find a -2 limit for example from the first product on
any of the x axes.

> Rresult <- corresp(mytable, nf=2)
> Rresult
First canonical correlation(s): 0.20823373 0.04840434

 Row scores:
        [,1]        [,2]
1 -2.0838424  0.01237391
2  0.4901559  1.51190922
3  0.4463375 -0.72631884
4  0.4946202 -0.87620237

 Column scores:
          [,1]        [,2]
1  -0.29870621 -0.32282847
2   0.04851042  0.73570925
3  -1.79584803  0.04537505
4   1.10904141  1.21563470
5  -0.35048140 -1.28883782
6  -1.80044987 -1.99532989
7   1.96987033  1.89925225
8   1.59225423 -0.42249233
9   1.96534193 -2.01733348
10  1.29641406 -0.67857429
11  0.33216906  0.05071065
12  0.12620111 -0.30281237
13 -0.59997905  1.90985228
14 -1.18972391 -0.46697874
15  0.34099302  0.55835672
16 -1.07356465  0.44743219
17  0.32569239 -1.21741819
18  0.07133121  0.20777127

Thank you for your patience.
am

	[[alternative HTML version deleted]]

