So, I am eagerly firing up a new game to test out all the new goodies, but had a quick question on anti-missile decoys. I get the building mechanics, but I would assume that the decoy signature should be roughly the same as the launching ship, should it not?
Reason for the ask is a couple of autobuilt designs are 16k tons and have decoys with 8k signature strength, which seems wrong. But I thought I would ask as I may be missing something. 
The chance of an incoming missile getting fooled by a decoy is proportional to the ratio of total launched decoy signature vs ship tonnage. The full formula is somewhere in the 2.3.0 changelogs I think.
If you have a 16k ton ship that launches a single 8k decoy, the chance of a missile instead going for a decoy is 8,000 / (8,000 + 16,000) = 33% chance the missile attacks the decoy instead.
Note that you can launch multiple decoys, so in the above scenario if the ship were to launch 2 decoys it would be (8,000 x 2) / ((8,000 x 2)+ 16,000) = 50% chance the missile attacks a decoy instead. This is why the signature of the decoy is less than the ships, it doesn't need to be equal for it to have a significant effect.
Finally, the above assumes that there is no ECM advantage vs the missiles ECCM. An ECM advantage acts as a multiplier on the decoy's signature, IIRC an ECM advantage of 5 would double the effective signature of the decoy and an ECCM advantage of 5 will make the missiles completely ignore the decoys.
