9. Eigenvalues of Dimensions Dimension F1 Eigenvalue 0.095 explains 86.6% (0.095/0.109) of the Inertia or Variance. F1 Coordinates are derived using PCA.
10. Singular Value Singular value = SQRT(Eigenvalue). It is the maximum Canonical Correlation between the categories of the variables in analysis for any given dimension.
11. Calculating Chi Square Distance for Points-rows Chi Square Distance defines the distance between a Point-row and the Centroid (Average) at the intersection of the F1 and F2 dimensions. The Point-row 16-24 is most distant from Centroid (0.72).
12. Calculating Inertia [or Variance] using Points-rows XLStat calculates this table. It shows what Row category generates the most Inertia (Row 16-24 accounts for 72% of it)
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14. Contribution of Points-rows to Dimension F1 The contribution of points to dimensions is the proportion of Inertia of a Dimension explained by the Point. The contribution of Points-rows to dimensions help us interpret the dimensions. The sum of contributions for each dimension equals 100%.
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16. Squared Correlation = COS 2 If Contribution is high, the angle between the point vector and the axis is small.
17. Quality Quality = Sum of the Squared Correlations for dimensions shown (normally F1 and F2). Quality is different for each Point-row (or Point-column). Quality represents whether the Point on a two dimensional graph is accurately represented. Quality is interpreted as proportion of Chi Square accounted for given the respective number of dimensions. A low quality means the current number of dimensions does not represent well the respective row (or column).
28. Conclusion (continued) We have to remember that we can’t directly compare the Distance across categories (Row vs Column). We see that the 16-24 Point-row makes a greater contribution to Inertia and overall Chi Square vs the Good Point-column. This is because the 16-24 Point-row has a greater mass (207 occurrences vs only 98 for Good).