The WGCNA R package requires a user-defined soft-threshold (referred to as the “power” in the function call) based on visually observing the above graph; specifically, the scale-freeness. The first value above the threshold suggested by the WGCNA authors (0.95) was chosen as indicated by the graph. Combined with the negative slope indicated in the mean connectivity graph, we can assume that we have a scale-free network as required by WGCNA.