I'm sure several players already know this, but I seem to see a lot of people blaming luck for rolling four blanks or if their opponent rolled four natural hits, as if it's something that's supposed to be rare, so I thought this might be useful to those people who are not just complaining but actually want to understand a bit more about probabilities.
the basic thing every player know is averages: the chance of rolling a hit or crit on a red dice is 50%, or 0.5 in math notation, so if you roll 4 dice the average is 2. not that great, right? we all know sometimes we'll roll 4 and sometimes it might be zero, but how do you quantify that? with the binomial distribution, which tells you that, for 4 dice you'll get:
6% of the times: 4 hits/crits
25% of the times: 3
38% of the times: 2
25% of the times: 1
6% of the times: 0
ok so, 6% of the times isn't that much, or is it? well lets say you play 10 rounds and shoot for 10 rounds. now that's a 60% chance (6% times 10 rounds) you rolled 4 natural hits/crits in one round (or 4 natural blank/focus in one round). so it's not surprising it happened. it could be the first roll you made, or the last you made, it's still about a 60% chance you make that roll.
so what if I have a TL and focus? OK the binomial distribution tells you that:
78% of the times: 4 hits/crits
20% of the times: 3
2% of the times: 2
0.1 % of the times: 1
tiny % of the times: 0
see, even assuming you shoot with a TL+focus each round for 10 rounds , the chance of rolling only 2 hits/crits in one of those 10 rounds (even after rerolling and spending a focus) is about 20%. it's still a pretty significant chance! in fact, if you look at the number of rounds you play in a tournament, or across multiple tournaments, you'll see there's a pretty significant chance you'll roll zero or one hits even with a TL and focus.
as an example, in a tournament I played a few days ago, my opponent had a choice to move Vader in an aggressive position to focus fire on my Poe, and a more defensive position where he would receive decreased fire from my ships. he went for the risky choice, rolled below average, Poe survived, my ships rolled above average, he lost Vader and with it the game.
it's not that he necessarily made the wrong choice. if he had killed Poe it would have given him an advantage. but several times he complained about that roll. I got the impression he thought it was improbable. what I meant to show is that yes it was a deviation from average, but if you look at the binomial distribution and consider the number of rolls you're making, you can understand that those rolls do happen with pretty significant chances. it's not luck or lack thereof, but rather normal and expected probability distributions.
if you happen to like distributions, you could even take the 6% chance of rolling 4 natural hits and ask, how many times am I going to roll 4 hits with 4 dice in 10 rounds? well, you can make another binomial distribution, and see that you have about:
54% chance of rolling 4 natural hits zero times in 10 rounds,
34% chance to roll 4 natural hits 1 time in 10 rounds
10% 2 times
2% 3 times
so you see, rolling 4 natural hits several times in 10 rounds is not so unusual. and just as well, since the chance to get 4 natural hit is the same as the chance to get 4 natural non hits, the chance of rolling 4 natural zero hits several times in 10 rounds is pretty significant as well.
PS: I tried to keep the explanation simple and so the above is not intended as a rigorous statistical treatment, for example I have not discussed conditional probabilities (the probability for a roll to happen based on a previous roll).
Edited by XBear