---
tag: XB6HVVTS3Q
kind: concept
name: Extraction sums of squared loadings
sources:
  - wikipedia: en:253492@r1371953697
    locator: Factor analysis, section Practical implementation > Terminology
    note: adopted
    mention: wikipedia://en/253492#E2UN
    sections: [Summary]
inventory: [STMA2T084J]
---

## Summary

Initial eigenvalues and eigenvalues after extraction (listed by SPSS as "Extraction Sums of Squared Loadings") are the same for PCA extraction, but for other extraction methods, eigenvalues after extraction will be lower than their initial counterparts. SPSS also prints "Rotation Sums of Squared Loadings" and even for PCA, these eigenvalues will differ from initial and extraction eigenvalues, though their total will be the same.