Mental health data: Correspondence analaysis

library(vcdExtra)
library(ca)

data

data(Mental)
Mental.tab <- xtabs(Freq ~ mental+ses, data=Mental)

correspondence analysis

ca(Mental.tab)

## 
##  Principal inertias (eigenvalues):
##            1        2        3       
## Value      0.026025 0.001379 0.000298
## Percentage 93.95%   4.98%    1.08%   
## 
## 
##  Rows:
##              Well      Mild  Moderate Impaired
## Mass     0.184940  0.362651  0.218072 0.234337
## ChiDist  0.260798  0.042750  0.071404 0.238669
## Inertia  0.012579  0.000663  0.001112 0.013349
## Dim. 1  -1.608804 -0.183408  0.088085 1.471537
## Dim. 2   0.325873  0.636852 -1.882247 0.508858
## 
## 
##  Columns:
##                 1         2         3        4        5         6
## Mass     0.157831  0.147590  0.172892 0.231325 0.159639  0.130723
## ChiDist  0.184023  0.187374  0.063947 0.044398 0.171358  0.294334
## Inertia  0.005345  0.005182  0.000707 0.000456 0.004688  0.011325
## Dim. 1  -1.121556 -1.146751 -0.365921 0.055088 1.025228  1.783327
## Dim. 2  -0.518293 -0.313039 -0.597693 1.133091 1.174196 -1.669326

plot(ca(Mental.tab))