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Eckarbeiter

WG needs to learn to math

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You are missing a lot of math in your assumptions. 

Fire reduction of your target. Hitting the ship while it's using DCP. Hitting areas of the ship already on fire. Possibility of some of those hits being with AP and not HE. 

Edited by Ducky_shot
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8 minutes ago, Eckarbeiter said:

62% fire chance.

186 hits.

0 fires.

62% is more like, in the way you are thinking of it, closer to 26%:

https://wiki.wargaming.net/en/Ship:Fire#The_Calculation

 

Quote

The Calculation

The chance to set fire for a single high explosive shell hitting a ship is calculated by the following formula (the formulas for airborne rockets and bombs are similar):

 

Fire Chance = FRC · ( 1 - DCM1 ) · ( 1 - FP ) · ( FCB - IFHE + DE + Σ S )

where:

  • FRC — the ship's Fire Resistance Coefficient (see above).
  • DCM1 — the effect of the Damage Control System Modification 1 upgrade: 5% (0.05) with the upgrade installed, zero without.
  • FP — the effect of the Fire Prevention skill: 10% (0.10) with the skill, zero without.
  • FCB — the Projectile Base Fire Chance (see above).
  • IFHE — the effect of the IFHE commander skill: 1% (0.01) or 3% (0.03) depending on gun caliber, or zero without the skill.
  • DE — the effect of the Demolition Expert commander skill: 0.02 with the skill, zero without.
  • Σ S — the sum of the effects of the mounted Signals Victor Lima +1% chance of causing a fire for bombs and shells with a caliber above 160mm / +0.5% chance of causing a fire for bombs and shells with a caliber below 160mm. / +4% chance of causing flooding. and India X-Ray +1% chance of causing a fire for bombs and shells with a caliber above 160mm. / +0.5% chance of causing a fire for bombs and shells with a caliber below 160mm. / +5% to the risk of your ship's magazine detonating.: +0.01 or +0.005 each depending on gun caliber, else zero.

As an example, we can compare the chance of a single Benson high explosive shell lighting a fire on an enemy Bismarck.

  • The Tier VIII Bismarck is using Hull B (Top) (FRC of 0.6337) and Damage Control System Modification 1; his commander is not skilled at Fire Prevention.
  • Benson fires 127mm HE Mk. 32 with a 5.5% base fire chance. Her commander is a Demolition Expert (not IFHE) and is flying both the Victor Lima and India X-Ray signals.

The fire chance (per hit) would be:

(0.6337) x (1 - 0.05) x (1 - 0.00) x (0.055 - 0.0 + 0.02 + 0.01) = 5.12% fire chance

If the Bismarck commander acquires the Fire Prevention skill, the chance would then be:

(0.6337) x (1 - 0.05) x (1 - 0.10) x (0.055 - 0.0 + 0.02 + 0.01) = 4.61% fire chance

If the Benson commander didn't have Demolition Expert or the signals equipped, the chance would be:

(0.6337) x (1 - 0.05) x (1 - 0.10) x (0.055 - 0.0 + 0.0 + 0.0) = 2.98% fire chance

The above example can be used to demonstrate the usefulness of the Demolition Expert skill on certain ships, especially those with a high rate of fire and a low individual fire chance per shell (such as Atlanta, Gearing, or Akizuki).

So if we assume you are firing from a TX at a TX (non CV), your adjusted fire chance (real fire chance) is = 0.62*0.5005*0.95*0.90, assuming they took FP and DCM1 and the base shell's fire chance is 62%, you get ~26.5% fire chance.

Basically the way this game works is if you fire a shell with 100% fire chance, it doesn't actually START a fire 100% of the time, closer to 50% of the time assuming the target doesn't take FP or DCM1 (which would further reduce the chance. This is akin to torpedoes having 300% flooding chance, because the chance to cause floods is similarly not a straightforward binary state of yes or no.

Edited by _RC1138
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8 minutes ago, _RC1138 said:

62% is more like, in the way you are thinking of it, closer to 26%:

https://wiki.wargaming.net/en/Ship:Fire#The_Calculation

 

So if we assume you are firing from a TX at a TX (non CV), your adjusted fire chance (real fire chance) is = 0.62*0.5005*0.95*0.90, assuming they took FP and DCM1 and the base shell's fire chance is 62%, you get ~26.5% fire chance.

Basically the way this game works is if you fire a shell with 100% fire chance, it doesn't actually START a fire 100% of the time, closer to 50% of the time assuming the target doesn't take FP or DCM1 (which would further reduce the chance. This is akin to torpedoes having 300% flooding chance, because the chance to cause floods is similarly not a straightforward binary state of yes or no.

Thank you for the reply... just annoyed at the fire % chance making no sense to me.

I just played in the Atlanta, got 120 shell hits and 13 freaking fires.... wiht a 4% fire chance per shell.

 

ugh

Edited by Eckarbeiter

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Heyo Everyone.

While it looks like @_RC1138 has already provided the proper calculation and impacts for fire chance (thanks for that!), please consider that many aspects of the game are deeper and involve more considerations/calculations than appear on the surface.

If you're looking for information on how certain calculations / factors work there are some great resources that you can use including:

All else fails, please don't hesitate to ask here in the forums, I would just encourage you to ask without insult in future!

Fem, 

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17 minutes ago, Eckarbeiter said:

Thank you for the reply... just annoyed at the fire % chance making no sense to me.

I just played in the Atlanta, bot 120 shell hits and 13 freaking fires.... wiht a 4% fire chance per shell.

 

ugh

If you know how the equation actually behaves, and that some skills/flags/upgrades are multiplicative and others are additive, you understand where things make more sense and less others. For example, on low fire% shells, always take DE, as the effect is *additive* meaning it's relative increase is HIGHER the lower the base shell chance. For example, I have a shell with 3% fire chance base, I add DE, it goes up to 6%, 100% increase, on the flip side you have say a BB shells with a 56% base chance, DE brings it to 59%, or only an ~5% increase. This is why say, USN DD's, should *always* take DE, as it makes a big difference, vs. say RN BB's, on which it has a near nonexistent effect.

Similarly FP's *fire reduction chance* is almost meaningless, depending on the tier/base shell chance, only actually reducing fire chance on yourself by MAYBE 1%, probably closer to 0.75% most of the time (despite the in game description quoting 10%, in practical application within the calculation, it's closer to ~0.75% most of the time).

Edited by _RC1138

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10 minutes ago, Eckarbeiter said:

Thank you for the reply... just annoyed at the fire % chance making no sense to me.

I just played in the Atlanta, got 120 shell hits and 13 freaking fires.... wiht a 4% fire chance per shell.

 

ugh

Atlanta is a bit of special case.  It gets to often shoot targets that are of higher tier, which negatively impacts its ability to start fires.  Plus substantial number of high tier BBs (compared to lower tiers) uses skills and signals that further reduce your fire chances.  Hence Atlanta will often score ridiculous amount of hits with very few fires.  If you want more level playing field with reliable fire starting ability, you may want to give Conqueror a try.

<edit> Atlanta commanders often utilize IFHE to better their direct damage capability, which also reduces already small chances to start fires.

Edited by Ramsalot

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13 minutes ago, Eckarbeiter said:

Thank you for the reply... just annoyed at the fire % chance making no sense to me.

I just played in the Atlanta, got 120 shell hits and 13 freaking fires.... wiht a 4% fire chance per shell.

 

ugh

Yea but your spewing out shells at an incredible rate of fire so should you no have trouble starting fires if you stay on point .

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6 minutes ago, clammboy said:

Yea but your spewing out shells at an incredible rate of fire so should you no have trouble starting fires if you stay on point .

For sure.

I wasn't understanding all the hidden math, and other stuff involved... and only was looking at this data:

186 hits @ 62% fire chance for 0 fires.  (nowhere near 62%... in fact.. it was 0% of my shells that led to fires)
120 hits @ 4% fire chance for 13 fires.  (Way the EFF more than 4%... it was almost 11% of my shells led to fires)

This bothered me.

EDITED: All bot games farming the fires for the weeb missions.  Not even sure why I'm doing this...  I won't ever use them.

Edited by Eckarbeiter

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5 minutes ago, Eckarbeiter said:

For sure.

I wasn't understanding all the hidden math, and other stuff involved... and only was looking at this data:

198 hits @ 62% fire chance for 0 fires.
120 hits @ 4% fire chance for 13 fires.

This bothered me.

All bot games farming the fires for the weeb missions.

Yea well it is a little complicated to understand sometimes . But  _Rc1138 is the math man he will always explain it when we get it wrong .

Edited by clammboy

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16 minutes ago, Ramsalot said:

Atlanta is a bit of special case.  It gets to often shoot targets that are of higher tier, which negatively impacts its ability to start fires.  Plus substantial number of high tier BBs (compared to lower tiers) uses skills and signals that further reduce your fire chances.  Hence Atlanta will often score ridiculous amount of hits with very few fires.  If you want more level playing field with reliable fire starting ability, you may want to give Conqueror a try.

<edit> Atlanta commanders often utilize IFHE to better their direct damage capability, which also reduces already small chances to start fires.

Perhaps you should do the math on 13/120 and realize it was overperforming before arguing why it might be underperforming. 

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11 minutes ago, Eckarbeiter said:

All bot games farming the fires for the weeb missions.

RNG denying you what you need.

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30 minutes ago, Ducky_shot said:

Perhaps you should do the math on 13/120 and realize it was overperforming before arguing why it might be underperforming. 

I am not sure it's overperforming.  I did quick math on the premium T7 CLs I have in my port using stock values, and here's what I see:

image.png.09026514cda0c98aa44796c8336581d4.png

IFHE does not skew this stock calculation, because my 19 pointer on Atlanta does not have room for Demo Expert, but Lazo and Belfast both can fit DE comfortably, so the numbers don't get affected.  One thing I can say for sure, is that Lazo and Belfast have higher proportion of shells they do not miss when compared to Atlanta, so if anything Atlanta is underpeforming in fire starting capability when compared to other premium CLs.  I can't seem to edit the image on this thing...

image.png

Edited by Ramsalot

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Just curious, how do you get 62% base fire chance to begin with?

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9 minutes ago, Ramsalot said:

I am not sure it's overperforming.  I did quick math on the premium T7 CLs I have in my port using stock values, and here's what I see:

image.png.09026514cda0c98aa44796c8336581d4.png

IFHE does not skew this stock calculation, because my 19 pointer on Atlanta does not have room for Demo Expert, but Lazo and Belfast both can fit DE comfortably, so the numbers don't get affected.  One thing I can say for sure, is that Lazo and Belfast have higher proportion of shells they do not miss when compared to Atlanta, so if anything Atlanta is underpeforming in fire starting capability when compared to other premium CLs.  I can't seem to edit the image on this thing...

image.png

It was a calculation simply based on shells hit, not fires per minute and reload speed, etc. 13 fires in 120 hits is well above 4% fire chance

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Fire chance is also calculated on a per shell basis, not on the total number of shell hits. Even if you assume some ridiculous fire chance like 90 or 99% combined with a 0% enemy fire resistance coefficient and never hitting a ship with a fire or dcp active, it’s still possible to go an entire game without setting a single fire. Over a substantially high number of shell hits in that scenario (well into the tens or hundreds of thousands and likely way higher) you’d see 90 or 99% of your hits setting fires, but within the space of a few games you could have one game with 100 hits and no fires and one game with 15 hits and 14 fires.

It’s no different that rolling a die. With six sides with an equal 1 in 6 chance of landing on side X, just rolling one die six times or rolling six dice will not guarantee at least one lands on side X. But roll that die 1000 times and you might get X 10-12% of the time, and if you roll it 10,000 times you’ll probably get pretty close to the expected 1700 Xs. 

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16 minutes ago, Skpstr said:

Just curious, how do you get 62% base fire chance to begin with?

DE/IFHE Thunderer (or IFHE with the fire flags) is the only ship I can think of that would be able to get 62% exactly

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21 minutes ago, Skpstr said:

Just curious, how do you get 62% base fire chance to begin with?

Thunderer has 63%.

That said, who the [edited] wastes salvos on Thunderer on HE when it has the best overall BB AP (especially when considering the platform/reload shooting it) in the whole bloody game?

Edited by _RC1138

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p(success) = 1 - p(failure). 

If you assume no fire reduction at all, even in the hull fire coefficient, then a single shell with 62% fire chance has a 38% chance of NOT lighting a fire.

The chance of 186 hits not starting a fire is 0.4186, or something vanishingly small but not zero.

With your Atlanta, you have a 4% fire chance, 96% chance of failing, and in 120 hits your chance of starting one is 1 - (0.96120) or 0.7%

RNGesus giveth and RNGesus taketh away.

55 minutes ago, Eckarbeiter said:

Not even sure why I'm doing this... 

Snowflakes. Even coal is valuable, and you have five coal flakes built into those ships (unless they move the steel bar down to T7).

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I actually think the prime word here is "chance" not promise!

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the only way to guarantee you no fires is to be working a mission objective that requires you to start them. sort of like working a mission requiring cap/defended flags you are guaranteed a steady diet of standard battles

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One other factor is whether the target is already burning. If you hit an area already on fire, you have zero chance to light a fire with that shell hit.

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1 hour ago, _RC1138 said:

Thunderer has 63%.

That said, who the [edited] wastes salvos on Thunderer on HE when it has the best overall BB AP (especially when considering the platform/reload shooting it) in the whole bloody game?

I do, and while game number count is low like 25games I am in the upper upper echelon of players that have it and play. And no one considers me good. Using anything but HE is lunacy unless you have golden gift wrapped potatoes.

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3 hours ago, Leslie_Reigart said:

the only way to guarantee you no fires is to be working a mission objective that requires you to start them. sort of like working a mission requiring cap/defended flags you are guaranteed a steady diet of standard battles

HA!

I don't think I'm remembering this wrong... but I probably am.  I swear that last year, you could randomly get "bonus" missions added to you at the start of a match.  I believe the (2) funniest I ever got were a "start 4 fires" while on an edinburg (it has no HE shells.... I mean the secondaries), and a get x# of secondary hits while playing on a wooster (no secondaries).  

Oh well.  I got all the fires done.  I'm stupid and just played CV sky cancer, dropping british HE bombs that pretty much cause 1-2 fires per drop.  I apologize to the poor ships I burned, and the teammates I screwed over because I did nothing but try to start fires for a few games.  :)

Torps was a lot easier.  156 torps in 1 game in the Benham got me 22 of the 30 hits.

Hmm... I wonder if we're supposed to go after these missions like this, rather than actually just get them while playing normally.  I've definitely been an even worse teammate than I normally am with all the kill stealing, fire starting, and torp hits against targets that can take as many as possible...   rather than actually trying to do anything that leads to a victory.

Edited by Eckarbeiter

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