Skip to main content
. 2019 Feb 13;14(2):e0211219. doi: 10.1371/journal.pone.0211219

Fig 8. The first principal component obtained via PCA accounts for over 90% of the variation in test performance.

Fig 8

(b) Similar levels of variance are accounted for by taking only the normal component of the first principal component, θ, in the breathing frequency direction.