For a Lambda Class Shuttle, assuming no defensive focuses, which 4 point upgrade lends the most survivability?
Our options are:
*Edit: The ship in question is to be flown by Captain Yorr, whom I wish to last as long as possible. Assume that I do not get any actions all game, and assume that I won't swap out the Lambda for a different set of ships.
Edited by DraconPyrothayanEngine upgrade..
Engine upgrade..
I'm looking at Captain Yorr, so I'm not planning on having many actions available at all.
So you have 28 points to spend on your squad. In my testing the lambda is not worth the points regardless of upgrades. The dial gives it no chance if a ship gets to your rear. In every game ice played with of against the shuttle it was last to be around and stood no chance vs 2 ships ( no matter what the other ships were ). Yorr is especially a dead duck as the extra stress will prevent him from hitting the breaks for the other guy to fly by.
So you have 28 points to spend on your squad. In my testing the lambda is not worth the points regardless of upgrades. The dial gives it no chance if a ship gets to your rear. In every game ice played with of against the shuttle it was last to be around and stood no chance vs 2 ships ( no matter what the other ships were ). Yorr is especially a dead duck as the extra stress will prevent him from hitting the breaks for the other guy to fly by.
Afraid that Yorr is required for my fleet build, and is going to be acting a bit like Biggs Darklighter. I am giving him a Rebel Captive to punish them for shooting at him in the first place, but really really really want to know which of the 3 options in the original post would be statistically the best option.
Before you said Yorr I was going to say advanced sensors so that you can always focus.
Flight instructor probably won't fire enough with the new trend towards mid-level PS, but if you know swarm is coming...maybe.
Jammer is also interesting but I never see it pan out (although some rebel {scum} swear by it on Bwings). I think the real cost here is you can't take fire control system or advanced sensors if you take this.
Sheild is sheild. Garunteed to extend your life by one hit.
You have a three way comparison requesting numerical comparison, but one of the three can't be solved by numerical comparison. 
Engine Upgrade is probably the best by far for strategic reasons.
For brute force number crunching to compare shield vs see my recent post in the other thread. In general, it's impossible to compute unless you pre-define what the attacks will be ahead of time.
Your math in the other thread was a bit off due to misreading the card in question. Flight Instructor lets you reroll blanks against pilots of level 2 or lower, but not focii, so it's the 9/64 question I mentioned.
That being said, I've seen several threads where people have posted the variance as determined by the different attack patterns (Tie Fighter through HLC, so 2, 3 and 4 attack dice, usually including separate results for Focus and Target Lock actions, but ignoring individual pilot abilities).
Actually, I think I parsed it correctly.
"When defending, you may reroll 1 of your [focus] results. If the attacker's pilot skill value is "2" or lower, you may reroll 1 of your blank results instead."
(emphasis mine)
It only says that you MAY reroll 1 blank result instead, it does not say that you CANNOT any longer choose to reroll a focus result.
I.e. the card says:
You may [A]
If [X], you may do .
If [X] is true, you can choose not to perform , in which case [A] is still in effect.
It probably warrants a FAQ from FFG, but until then I don't see any reason that it has to be interpreted otherwise.
Edited by MajorJugglerThought I'd get my own thoughts on paper here for a bit. Sorry for the brain-vomit.
1: Shield Upgrade: Increase your Shield Value by 1.
Guaranteed to be 1 hit avoided, and ignores the difference for hits and crits for that one hit. Not too shabby, and no math needed.
2: Flight Instructor: When defending, you may re-roll 1 of your 
focus results. If the attacker's pilot skill value is "2" or lower, you may re-roll 1 of your blank results instead.
Math required. For 1 evasion die, you have a 2/8 and 3/8 chance to re-roll, respectively. At that point, you have a 3/8 chance of rolling an evasion. As we're assuming no defensive actions, the math stops there. This gives us 6/64 (3/32) or 9/64 increased odds of dodging with our one die. Percentagewise, that brings the 37.5% of evading naturally to appx. 47% and 52%, respectively.
3: Sensor Jammer: When defending, you may change 1 of the attacker's hit results into a focus result. The attacker cannot re-roll the die with the changed result.
If your opponent has not focused, this is 1 damage negated from their every attack, like getting an Evade Token every time they attack me. If they intend to spend their focus offensively, this has done nothing. If they are unsure one way or another, they're in a tight spot.
That brings us to basically 2 questions:
Do the re-rolls of the Flight Instructor average into at least one additional dodge across the expected life of the Shuttle? If not, the Shield Upgrade is a better use of 4 points.
For this question, we must ask the secondary question of "What is the expected life of the shuttle?", which depends on the ships firing at me. Specifically, it depends on their attack dice (2, 3, and 4) and expected offensive actions (Target Lock and Focus), as weighed against the original evasion statistics of the Shuttle vs the adjusted evasion stats with the Flight Instructor. This question is the reason I specifically requested number-crunchers, as may people on this site have written programming scripts to do the math for us.
Through my skill in flight, can I prevent my opponent from spending focuses offensively, or punish them from doing so? If not, the Shield Upgrade is a better use of 4 points.
As I am flying three Interceptors, and am using a Rebel Captive on my shuttle, this is starting to look more appealing. If I can prevent their actions from Captive-Stress or Interceptor-Collision twice, then Sensor Jammer is better than a Shield Upgrade. Moreover, since I am flying 3 Interceptors, the use of the focus offensively will let me deal some serious damage with my 3 attack dice.
Also: I just realized that they needed to add "instead", because otherwise you could reroll TWO dice: one focus, and one blank. Obviously this could only happen at range 3, but it could still happen.
Edited by MajorJugglerActually, I think I parsed it correctly.
"When defending, you may reroll 1 of your [focus] results. If the attacker's pilot skill value is "2" or lower, you may reroll 1 of your blank results instead."
(emphasis mine)
It only says that you MAY reroll 1 blank result instead, it does not say that you CANNOT any longer choose to reroll a focus result.
I.e. the card says:
You may [A]
If [X], you may do .
If [X] is true, you can choose not to perform , in which case [A] is still in effect.
It probably warrants a FAQ from FFG, but until then I don't see any reason that it has to be interpreted otherwise.
I read it as: "If [X], you may [A]. If [Y], you may . You are not compelled to [A] or .", but I will accept the FAQ neutrality compromise.
Actually, I think you read it some other way. That would allow you to perform both [A] and if both [X] and [Y] conditions are met.
"You are not compelled to [A] or " is necessarily implied by using the term "may" before each.
Think of it this way: change the text of the card to: