Good Afternoon,
I have a quick question regarding the use of the NBS statistics toolbox within Graphvar. If I have two groups and from each have calculated a mean network for each group, can I use the NBS package to compare the two mean graphs. I worry that this wouldnt be statistically valid in the sense that the sample would effectively be two.
Instead would I need to run a test like the hamming distance to compare two individual mean networks? If so is this within the scope of the Graphvar program?
Forums
Only 2 matrices significance
Hi Both,
Hi Both,
Thanks for your help, it is much appreciated.
In terms of the data, the graphs are derived from correlations between cortical thickness measurements of brain regions. Therefore, as each pair of regions has only a single measurement in each participant, only a group-level graph can be generated. Therefore, because the edgeweight is the correlation-coefficient itself and not the mean of multiple correlation-coefficients I believe it wouldnt be possible to generate a variance matrix.
In your approach, am I right in thinking it wouldn't be neccesary to run the get_component function if I just wanted to look at the individual links of the graph and their significance?
BW
Dan
Hi Dan,with the described
Hi Dan,
with the described approach you can also just examine specific connections and you would not have to run the get_component code... although it may be interesting. In my experience, performing a conservative FDR link-based controlling procedure often result in similar/overlapping "graph components" as when identifiying significant graph components with the NBS procedure.
Best,
Johann
Hi Johann,
Hi Johann,
Thanks for clearing that up. I'm sorry for my naivity, but you say that the comparison could be written in Matlab easily. I have limited experience with the BCT scripts and am unsure how I would go about this, any pointers?
Sorry to bug you!
Best wishes,
Dan