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help > RE: ROI-to-ROI 2nd level results in Results Explorer : Cluster values from Connections values
Oct 11, 2022 09:10 PM | Alfonso Nieto-Castanon - Boston University
RE: ROI-to-ROI 2nd level results in Results Explorer : Cluster values from Connections values
Hi Mathilde,
The statistics for the whole cluster are computed in different ways depending on your choice of inferential method used (see the "Cluster-level inferences in ROI-to-ROI analyses" section in https://web.conn-toolbox.org/fmri-methods/cluster-level-inferences for details), and they represent a property of the cluster (e.g. its size) which cannot be summarized from a set of aggregated cluster-level values / datapoints. That said, for interpretation purposes I typically recommend simply averaging the values extracted across all of the connections within the cluster, and displaying those values, even if the stats resulting from analyzing those post-hoc datapoints will not match the stats associated with the cluster (note: to clarify, the same thing happens in typical voxel-level analyses, where the stats associated with a cluster -a group of voxels in this case- are typically derived from each cluster size or other properties of each cluster, and they do not match the stats resulting from running the same analyses on the data averaged across all voxels within a cluster)
Hope this helps
Alfonso
Originally posted by mathilde31:
The statistics for the whole cluster are computed in different ways depending on your choice of inferential method used (see the "Cluster-level inferences in ROI-to-ROI analyses" section in https://web.conn-toolbox.org/fmri-methods/cluster-level-inferences for details), and they represent a property of the cluster (e.g. its size) which cannot be summarized from a set of aggregated cluster-level values / datapoints. That said, for interpretation purposes I typically recommend simply averaging the values extracted across all of the connections within the cluster, and displaying those values, even if the stats resulting from analyzing those post-hoc datapoints will not match the stats associated with the cluster (note: to clarify, the same thing happens in typical voxel-level analyses, where the stats associated with a cluster -a group of voxels in this case- are typically derived from each cluster size or other properties of each cluster, and they do not match the stats resulting from running the same analyses on the data averaged across all voxels within a cluster)
Hope this helps
Alfonso
Originally posted by mathilde31:
Hello,
I'm doing some ROI-to-ROI analysis and comparing two time conditions.
I can find some changes of connectivity in one cluster formed by several ROI-to-ROI connections. I know how to extract the data from these connections using "import values", but I would like to know how the "values" of the whole cluster are calculated to end up with the statistics from the whole cluster?
I mean I would like to be able to do a t-test on another statistical software with the values from the whole cluster to find the same stats and to plot them.
Hope my question is clear.
Thanks in advance,
Mathilde,
I'm doing some ROI-to-ROI analysis and comparing two time conditions.
I can find some changes of connectivity in one cluster formed by several ROI-to-ROI connections. I know how to extract the data from these connections using "import values", but I would like to know how the "values" of the whole cluster are calculated to end up with the statistics from the whole cluster?
I mean I would like to be able to do a t-test on another statistical software with the values from the whole cluster to find the same stats and to plot them.
Hope my question is clear.
Thanks in advance,
Mathilde,
Threaded View
| Title | Author | Date |
|---|---|---|
| mathilde31 | Oct 7, 2022 | |
| Alfonso Nieto-Castanon | Oct 11, 2022 | |
| mathilde31 | Oct 12, 2022 | |