The way that Mandalorion calculates mean qual isn't consistent with Albacore

[conchoecia]

Right now mandalorion uses the geometric mean to calculate a cutoff for read quality, but this leads to artificially inflated mean scores. Albacore reports the arithmetic mean. This may cause confusion if the user sees one average score for a read with one program, and another with Mandalorion.

Check out this discussion and this blog post.