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**Graph theory**Apr 12, 2024 12:04 PM | Or Mizrahi

Graph theory

We have resting state data from 30 participants for which we
want to examine Graph Theory metrics in a network of 18
language-related ROIs that we have defined.

In order to determine the first-level threshold we should use
we produced a graph of the global and local efficiencies as a
function of the threshold, by leaving the threshold box empty (as
suggested in this post). A
screenshot is attached for both the cost and correlations.

As the legend is illegible I would like to ensure that the
solid line represents my data, the dotted line represents the
Lattice, and the dashed line represents the Random. Is this
correct?

If I understand correctly, the graph on the right describes
the calculation of the formula
(GE_data-GE_lattice+LE_data-LE_random), and the chosen
threshold should maximize this value. Can you help me understand
which threshold value answers that according to my
data?

**My questions are:**

1. What does it mean about my data that the graph is negative,
and the maximum value is close to zero? would you still recommend
using this point as the threshold?

2. I see that many studies use a range of thresholds. How
should I use this graph to determine the range of thresholds to
use?

3. When using a range of thresholds how should I report the
results across the different thresholds? Is it ok to average Graph
Theory metrics (e.g. global and local efficiency) across
thresholds?

4. Is there a way to implement a range of thresholds in the
conn GUI?

I really appreciate any help you can provide.