TY - GEN
T1 - High dimensional exploration
T2 - 5th IEEE Symposium on Computational Intelligence and Data Mining, CIDM 2014
AU - Etzel, Joset A.
AU - Braver, Todd S.
N1 - Publisher Copyright:
© 2014 IEEE.
PY - 2015/1/13
Y1 - 2015/1/13
N2 - fMRI (functional magnetic resonance imaging) studies frequently create high dimensional datasets, with far more features (voxels) than examples. It is known that such datasets frequently have properties that make analysis challenging, such as concentration of distances. Here, we calculated the probability of distance concentration and proportion of variance explained by PCA in two fMRI datasets, comparing these measures with each other, as well as with the number of voxels and classification accuracy. There are clear differences between the datasets, with one showing levels of distance concentration comparable to those reported in microarray data [1, 2]. While it remains to be determined how typical these results are, they suggest that problematic levels of distance concentration in fMRI datasets may not be a rare occurrence.
AB - fMRI (functional magnetic resonance imaging) studies frequently create high dimensional datasets, with far more features (voxels) than examples. It is known that such datasets frequently have properties that make analysis challenging, such as concentration of distances. Here, we calculated the probability of distance concentration and proportion of variance explained by PCA in two fMRI datasets, comparing these measures with each other, as well as with the number of voxels and classification accuracy. There are clear differences between the datasets, with one showing levels of distance concentration comparable to those reported in microarray data [1, 2]. While it remains to be determined how typical these results are, they suggest that problematic levels of distance concentration in fMRI datasets may not be a rare occurrence.
KW - MVPA
KW - PCA
KW - distance concentration
KW - fMRI
KW - support vector machines
UR - http://www.scopus.com/inward/record.url?scp=84925064663&partnerID=8YFLogxK
U2 - 10.1109/CIDM.2014.7008662
DO - 10.1109/CIDM.2014.7008662
M3 - Conference contribution
AN - SCOPUS:84925064663
T3 - IEEE SSCI 2014 - 2014 IEEE Symposium Series on Computational Intelligence - CIDM 2014: 2014 IEEE Symposium on Computational Intelligence and Data Mining, Proceedings
SP - 157
EP - 162
BT - IEEE SSCI 2014 - 2014 IEEE Symposium Series on Computational Intelligence - CIDM 2014
PB - Institute of Electrical and Electronics Engineers Inc.
Y2 - 9 December 2014 through 12 December 2014
ER -