I'm using a data-set with 22 attributes in WEKA and after applying the PrincipalComponents attribute evaluator I get 8 ranked attributes with 0.95 variance covered. As far as I know, the sum of the new values of the attributes should be equal to 0.95, but for some reason my ranked attribute variance doesn't add up to. What's the issue with it?
All of the attributes are numeric, except for the class attribute which is nominal.
Here it is - the output I get in WEKA after PCA:
Ranked attributes
Any help is appreciated, thank you.
The variances being totaled by yourself are scores derived from cumulative variances.
Please refer
Answer by Mark Hall:
http://weka.8497.n7.nabble.com/PCA-Output-td3579.html
And
Q&A on PCA variances add to 100%
https://stats.stackexchange.com/questions/32901/do-components-of-pca-really-represent-percentage-of-variance-can-they-sum-to-mo
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