Difference between revisions of "Stacking penalties"

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== Stacking penalties ==
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'''Stacking penalties''' refer to an effectiveness reduction that is incurred when using two or more [[module]]s or [[rig]]s that affect the same attribute. The more modules or rigs affect the same attribute, the less effective each additional module is; in practice, having more than three or four modules/rigs affecting the same attribute is not worth it.
  
Stacking penalties refer to an effectiveness reduction that is incurred when using two or more modules or rigs that affect the same attribute. Most, but not all, mods show in their description if they are subject to this. Modules affected by stacking penalty multiplier include, but are not limited to: Electronic warfare (target painters, webbers), resistance bonuses (hardeners, etc), ship speed modules (nanofiber structure, inertia stabilizers and overdrive injectors), and others.  
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Most (but not all) modules and rigs will show in their description if they are subject to stacking penalties.  
  
Note that it is the stat bonus that is affected, not the module itself. For example, if you have a nanofiber internal structure (agility and velocity) and an overdrive injector system (velocity), the nano's velocity bonus would suffer a stacking penalty, but not its agility bonus. Similarly with armour or shield resistance modules: if you fit an EM hardener, an explosive hardener and an omni-hardener (adaptive invulnerability field or adaptive nano plating); the EM/Exp resistances from the omni-hardener would be stacking-penalized but the Kin/Therm resistances would not.
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Note that it is the stat bonus that is affected, not the module itself. For example, if you fit both a Nanofiber Internal Structure (boosts agility and velocity) and an Overdrive Injector System (boosts velocity), the Nanofiber's velocity bonus would suffer a stacking penalty, but not its agility bonus. Similarly with armour or shield resistance modules: if you fit an EM hardener, an explosive hardener and an omni-hardener (Adaptive Invulnerability Field or Adaptive Nano Plating): the EM/Explosive resistances from the omni-hardener would be stacking-penalized but the Kinetic/Thermal resistances would not.
  
 
Also of note is that module drawbacks (negative effects) can also be stacking penalized.
 
Also of note is that module drawbacks (negative effects) can also be stacking penalized.
  
While additional modules are stacking penalized, some modules' bonuses affect each other. E.g. when fitting damage modules, the effects of the second and third module will be stacking penalized but as the damage and rate of fire (RoF) bonuses affect each other, the second damage mod will add more raw dps to the fit than the first damage mod did. E.g. when fitting a [[Brutix]], the first damage mod will bring the dps from 458 to 563 (+105) while the second will bring the damage from 563 to 674 (+111). The third damage mod will then "only" bring the dps from 674 to 757 (+83) so even though it is the third level in stacking penalties, it still adds nearly 80% the dps of the first one. Which modules' bonuses affect each other depends on the specific bonus formula and the author of this paragraph doesn't know for sure which ones besides damage mods do and which don't.
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== Effects of stacking penalities==
  
=== The Formula  ===
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Normally, the benefits of additional modules/rigs would be multiplicative. So if fitting one Speed Booster (a fictional module with nice round numbers to make the math easier to understand) module increases a ship's speed by 10%, fitting two of them would increase a ship's speed by 21% (<span style="white-space: nowrap;">(1 + 10%) &times; (1 + 10%) = 1.1 &times; 1.1 = 1.21</span>), and fitting three would increase it by 33% (<span style="white-space: nowrap;">1.1 &times; 1.1 &times; 1.1 = 1.33</span>).
  
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However, due to the stacking penalties effect, the second, third, and fourth Speed Booster modules' effects are only partially effective (86.9%, 57.1%, and 28.3% respectively - see [[Stacking penalties#The Formula|below]] for details), and would therefore only increase a ship's speed by:
 +
* <span style="white-space: nowrap;">10% &times; 86.9% = 9%</span> for the second module
 +
* <span style="white-space: nowrap;">10% &times; 57.1% = 5.7%</span> for the third module
 +
* <span style="white-space: nowrap;">10% &times; 28.3% = 2.8%</span> for the fourth module
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Therefore, the actual speed increase for the ship would be:
 +
* One Speed Booster module: +10%
 +
* Two Speed Booster modules: <span style="white-space: nowrap;">(1 + 10%) &times; (1 + (10% &times; 86.9%)) = (1 + 10.5%) &times; (1 + 9%) = +19.8%</span>
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* Three Speed Booster modules: <span style="white-space: nowrap;">(1 + 19.8%) &times; (1 + 5.7%) = +26.7%</span>
 +
* Four Speed Booster modules: <span style="white-space: nowrap;">(1 + 26.7%) &times; (1 + 2.8%) = +30.3%</span>
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However, the modules' bonuses still multiply, so even if the ''percentage'' increase of each subsequent module decreases sharply, the ''absolute'' increase of each subsequent module drops off more slowly. If we take a ship with a nominal speed of 100&nbsp;m/s:
 +
* Adding one Speed Booster module: <span style="white-space: nowrap;">100 + 10% = 110 m/s</span>, an increase of +10&nbsp;m/s
 +
* Adding a second Speed Booster module: <span style="white-space: nowrap;">110 m/s + 9% = 120 m/s</span>, an additional increase of +10&nbsp;m/s
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* Adding a third Speed Booster module: <span style="white-space: nowrap;">120 m/s + 5.7% = 127 m/s</span>, an additional increase of +7&nbsp;m/s
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* Adding a fourth Speed Booster module: <span style="white-space: nowrap;">127 m/s + 2.8% = 130 m/s</span>, an additional increase of +3&nbsp;m/s
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 +
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== The Formula  ==
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[[image:StackingPenaltyGraph.png|400px|thumb|The effectiveness of stacking penalized modules polotted.]]
 
Stacking-penalized modifiers are applied one at a time, in descending order of strength.  
 
Stacking-penalized modifiers are applied one at a time, in descending order of strength.  
  
 
The ''n''-th modifier is multiplied by S(''n''-1), as follows:
 
The ''n''-th modifier is multiplied by S(''n''-1), as follows:
  
: S(''u'') = e<sup>-(''u'' / 2.67)<sup>2</sup></sup>
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:<math> S(u) = e^{-(u / 2.67)^2} </math>
  
 
=== The Numbers  ===
 
=== The Numbers  ===
[[File:StackingPenaltyGraph.png|200px|right]]
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The exact numbers for stacking penalties can be gained by the formula above, but here are some rounded guidelines for quick calculations that doesn't need to be precise:
 
* 1st mod: 100.0% effectiveness
 
* 1st mod: 100.0% effectiveness
* 2nd mod: 86.9% effectiveness
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* 2nd mod: ~86.9% effectiveness
* 3rd mod: 57.1% effectiveness
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* 3rd mod: ~57.1% effectiveness
* 4th mod: 28.3% effectiveness
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* 4th mod: ~28.3% effectiveness
* 5th mod: 10.6% effectiveness
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* 5th mod: ~10.6% effectiveness
* 6th mod: 3.0% effectiveness
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* 6th mod: ~3.0% effectiveness
 
 
 
As is clear, stacking more than 3 or 4 modules or rigs - unless you really have nothing else at all that you could fit there - that affect the same stat is fairly pointless, as your benefit is so tiny.
 
As is clear, stacking more than 3 or 4 modules or rigs - unless you really have nothing else at all that you could fit there - that affect the same stat is fairly pointless, as your benefit is so tiny.
  
=== What suffers stacking penalties? ===
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== What suffers stacking penalties? ==
  
*The first thing to note is that absolute effects are never stacking-penalized, only percentage effects. That is to say, things like +1 warp core strength, +1000 structure HP, +15m signature radius, +400 GJ capacitor are not stacking-penalized because they are not percentage (%) effects.  
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# Absolute effects are never stacking-penalized, only percentage effects. That is to say, things like +1 warp core strength, +1000 structure HP, +15&nbsp;m signature radius, +400&nbsp;GJ capacitor are not stacking-penalized because they are not percentage (%) effects.
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# Only modules, rigs, the effects of [[Command Bursts]] and enviromental effects of [[Abyssal Deadspace]] are stacking-penalized. Skills, ship bonuses from ship skills, implants, hardwirings, [[Combat Booster|boosters]] (such as Synth Blue Pill, Strong X-Instinct, and others) and the effects of [[wormhole space]] are not stacking penalized.
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# Negative and positive effects are stacking-penalized separately. So, one +% and one -% effect to an attribute suffers no penalties, whereas with two +% and two -% effects, one of each would only be 86.9% effective. An example might be velocity modifiers: if you have one Overdrive Injector System on your ship (to increase your speed) whilst at the same time being slowed by a single Stasis Webifier from an enemy ship - both velocity modifers are 100% effective. If you are then affected by second Stasis Webifier (from the same or another ship) that second web will be only 86.9% effective.
  
*The second thing is that only modules and rigs are stacking-penalized. Skills, ship bonuses from ship skills, implants, hardwirings and boosters are not.
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It can be hard to tell exactly what suffers stacking penalties and what does not. For instance, the Overdrive Injector System II gives +12.5% velocity at a cost of -20% cargo capacity, and the description claims it suffers stacking penalties. The velocity bonus is stacking-penalized, but the cargo drawback is actually ''not''. Similarly, the Warp Core Stabilizer II gives you one extra warp core strength at a cost of -40% targeting range and -40% scan resolution. It doesn't mention stacking penalty in the description, but the drawbacks ''are'' actually stacking-penalized.  
  
*The third thing is that negative and positive effects are stacking-penalized separately. So, one +% and one -% effect to an attribute suffers no penalties, whereas with two +% and two -% effects, one of each would only be 86.9% effective. An example might be velocity modifiers: if you have one [http://wiki.eveonline.com/en/wiki/Overdrive_Injector_System_II Overdrive Injector System II] on your ship (to increase your speed) whilst at the same time being slowed by a single [http://wiki.eveonline.com/en/wiki/Stasis_Webifier_II Stasis Webifier II] from an enemy ship - both velocity modifers are 100% effective. If you are then affected by second Stasis Webifier II (from the same or another ship) that second web will be only 86.9% effective.
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We can learn from this that it is not the module itself which determines whether its effects are stacking-penalized, but rather the attribute affected.  
 
 
It can be hard to tell exactly what suffers stacking penalties and what does not. For instance, the [http://wiki.eveonline.com/en/wiki/Overdrive_Injector_System_II Overdrive Injector System II] gives +12.5% velocity at a cost of -20% cargo capacity, and the description claims it suffers stacking penalties. The velocity bonus is stacking-penalized, but the cargo drawback is actually ''not''. Similarly, the [http://wiki.eveonline.com/en/wiki/Warp_Core_Stabilizer_II Warp Core Stabilizer II] gives you one extra warp core strength at a cost of -40% targeting range and -40% scan resolution. It doesn't mention stacking penalty in the description, but the drawbacks ''are'' actually stacking-penalized.  
 
  
We can learn from this that it is not the module itself which determines whether its effects are stacking-penalized, but rather the attribute affected.  
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Assuming the attribute they affect is actually stacking penalized, [[Command Burst]] modules are stacking penalized as normal, along with the rest of your modules and rigs.
  
Here's a handy table of what ship effects are stacking-penalized and which aren't. There are some weird exceptions (marked with a <sup>#</sup> and talked about below the table) and may be incomplete. Remember, it is only ''percentage'' effects from modules/rigs that are penalized.
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Here's a handy table of what ship effects are stacking-penalized and which aren't; there are some weird exceptions which are further discussed below the table. Remember, it is only ''percentage'' effects from modules/rigs that are penalized.
  
=== Is ''<insert attribute>'' stacking-penalized? ===
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== Is ''<insert attribute>'' stacking-penalized? ==
  
 
{| class="wikitable"
 
{| class="wikitable"
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|-
 
|-
 
| Capacitor capacity
 
| Capacitor capacity
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| style="background: #003a00; text-align: center;" | no<ref name="capcap">Both the flat bonus from capacitor batteries and percentage bonus from micro warp drives and capacitor flux coils are unpenalized.</ref>
 +
|-
 +
| Capacitor recharge rate
 
| style="background: #003a00; text-align: center;" | no
 
| style="background: #003a00; text-align: center;" | no
 
|-
 
|-
| Capacitor recharge rate
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| Energy Warfare resistance
 +
| style="background: #3a0000; text-align: center;" | yes
 +
|-
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| Module capacitor use
 
| style="background: #003a00; text-align: center;" | no
 
| style="background: #003a00; text-align: center;" | no
 
|-
 
|-
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|-
 
|-
 
| Shield / armor / hull hit points
 
| Shield / armor / hull hit points
| style="background: #003a00; text-align: center;" | no
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| style="background: #003a00; text-align: center;" | no<ref name="hp">Both the flat bonuses and percentage bonuses are unpenalized.</ref>
 
|-
 
|-
 
| Shield / armor / hull resistances  
 
| Shield / armor / hull resistances  
| style="background: #3a0000; text-align: center;" | yes<sup>1</sup>
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| style="background: #3a0000; text-align: center;" | yes<ref name="dc">Damage Control modules and the Reactive Armor Hardener module work slightly differently.<p>If you only fit one or the other (one Damage Control ''or'' one Reactive Hardener), then they are ''never'' stacking penalized. They will ''always'' give their full damage resistance effect, along with your most effective module that also gives it's full effect as explained above, followed by any other modules that will be stacking penalized. This is one reason why the Damage Control module is so popular; because it is always 100% effective.</p><p>If, however, you fit ''both'', then one of them (whichever is less effective) will count as a second module and be stacking penalized accordingly (so, 86.9% effective). This is in addition to your normal resistance modules, of which one will give its full effect and the rest stacking penalized as explained above. </p><p>As an example, consider the following five modules all fitted to your ship and their resulting effectiveness:  one Damage Control ''(100% effective)'', and one Reactive Armor Hardener ''(86.9% effective)''; one Armor EM Hardener ''(100% effective)'', one Energized Adaptive Nano Membrane ''(EM resistance 86.9% effective, other resistances 100% effective)'', and one Adaptive Nano Plating ''(EM resistance 57.1% effective, other resistances 86.9% effective)''.</p></ref>
 
|-
 
|-
 
| Shield boost / armor repair bonus
 
| Shield boost / armor repair bonus
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| ECM jammer strength  
 
| ECM jammer strength  
 
| style="background: #3a0000; text-align: center;" | yes
 
| style="background: #3a0000; text-align: center;" | yes
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|-
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| Sensor dampener scan resolution dampening strength
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| style="background: #3a0000; text-align: center;" | yes
 +
|-
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| Sensor dampener targeting range dampening strength
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| style="background: #003a00; text-align: center;" | no
 
|-
 
|-
 
| Scan probe sensor strength  
 
| Scan probe sensor strength  
| style="background: #3a0000; text-align: center;" | yes<sup>2</sup>
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| style="background: #3a0000; text-align: center;" | yes<ref name="scan probes">The probe scan strength from Gravity Capacitor Upgrade rigs and Scan Rangefinding Arrays and Sisters & Tech 2 launchers are all stacking penalized, even though the rigs and launchers don't mention it. Sisters probes are not, because they are not percentage effects - the core probes have a base strength of 44 instead of 40 (or 22 instead of 20 in the case of Sisters combat probes).</ref>
 
|-
 
|-
 
| Scan resolution  
 
| Scan resolution  
Line 95: Line 126:
 
|-
 
|-
 
| Velocity
 
| Velocity
| style="background: #3a0000; text-align: center;" | yes
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| style="background: #3a0000; text-align: center;" | yes<ref name="velocity">There are two different velocity bonuses, the ''Maximum Velocity Bonus'' (propulsion modules such as afterburners and microwarpdrives) and the ''Velocity Modifier'' (propulsion upgrade modules such as nanifibers, overdrives etc). They stack separately and thus a MWD doesn't change the stacking order for multiple propulsion upgrades.</ref>
 
|-
 
|-
 
| Inertia modifier (agility)  
 
| Inertia modifier (agility)  
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|-
 
|-
 
| Duration (cycle time) bonuses (except weapons)  
 
| Duration (cycle time) bonuses (except weapons)  
| style="background: #003a00; text-align: center;" | no<sup>3</sup>
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| style="background: #003a00; text-align: center;" | no<ref name="nanobot">Although the Nanobot Accelerator rig (to decrease armor repairer cycle time) says it is stacking penalized in Show Info, it isn't.</ref>
 
|-
 
|-
 
| Missile launcher rate of fire  
 
| Missile launcher rate of fire  
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|-
 
|-
 
| Missile explosion velocity
 
| Missile explosion velocity
| style="background: #003a00; text-align: center;" | no
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| style="background: #3a0000; text-align: center;" | yes
 
|-
 
|-
 
| Missile explosion radius  
 
| Missile explosion radius  
| style="background: #003a00; text-align: center;" | no
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| style="background: #3a0000; text-align: center;" | yes
 
|-
 
|-
 
| Missile flight time  
 
| Missile flight time  
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|-
 
|-
 
| Turret tracking speed  
 
| Turret tracking speed  
| style="background: #3a0000; text-align: center;" | yes<sup>4</sup>
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| style="background: #3a0000; text-align: center;" | yes
 
|-
 
|-
 
| All optimal range (modules/turrets)
 
| All optimal range (modules/turrets)
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|-
 
|-
 
| Mining laser yield (including mining drone yield)  
 
| Mining laser yield (including mining drone yield)  
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| style="background: #003a00; text-align: center;" | no
 +
|-
 +
| Drone control range
 
| style="background: #003a00; text-align: center;" | no
 
| style="background: #003a00; text-align: center;" | no
 
|-
 
|-
 
| Drone damage  
 
| Drone damage  
 
| style="background: #3a0000; text-align: center;" | yes
 
| style="background: #3a0000; text-align: center;" | yes
 +
|-
 +
| Salvaging probability 
 +
| style="background: #003a00; text-align: center;" | no
 +
|-
 
|}
 
|}
  
=== Weird Exceptions ===
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Bonuses from overheating sometimes follow same stacking penalties as normal bonuses. But this is not always the case.
 +
 
 +
{| class="wikitable"
 +
|-
 +
! style="background:#222222;" | Overheated module (bonus)
 +
! style="background:#222222;" | Stacking-penalized
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|-
 +
| shield/armor repairer (repair ammount)
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| style="background: #3a0000; text-align: center;" | yes
 +
|-
 +
|-
 +
| Local/remote shield/armor repairer (cycle time)
 +
| style="background: #003a00; text-align: center;" | no
 +
|-
 +
| ECM strength bonus
 +
| style="background: #3a0000; text-align: center;" | yes
 +
|-
 +
| Sensor dampener (range dampening strength)
 +
| style="background: #003a00; text-align: center;" | no
 +
|-
 +
| Sensor dampener (resolution dampening strength)
 +
| style="background: #3a0000; text-align: center;" | yes
 +
|-
 +
| Guidance and tracking disruptors
 +
| style="background: #3a0000; text-align: center;" | yes
 +
|-
 +
| Target painters
 +
| style="background: #003a00; text-align: center;" | no
 +
|-
 +
| Warp disruptors, Warp scramblers and Stasis webifiers
 +
| style="background: #3a0000; text-align: center;" | yes
 +
|-
 +
| Afterburners and micro warp drives
 +
| style="background: #3a0000; text-align: center;" | yes<ref name="abmwd">Stacking penalized with rapid deploymend command burst. Not with speed boosting modules or rigs.</ref>
 +
|-
 +
| Turrets and missile launchers (damage bonus)
 +
| style="background: #003a00; text-align: center;" | no
 +
|-
 +
| Turrets and missile launchers (Rate of fire bonus )
 +
| style="background: #003a00; text-align: center;" | no
 +
|-
 +
| Capacitor transmitters
 +
| style="background: #003a00; text-align: center;" | no
 +
|-
 +
|}
 +
 
 +
Many overheating bonuses are not stacking penalized simply due to the fact that there are no modules or effects that would modify the same stat as the overheat bonus.These modules are considered to be not stacking penalized until an efect that modifies same stat as the overheat bonus is released.<br>
 +
Modules with no overlaping effects: 
 +
* Sensor boosters
 +
* Capacitor boosters
 +
* Tracking/guidance computers
 +
* omnidirectional tracking links
 +
* Hull repairers
 +
* Active hardeners
 +
* Energy neutralizers and nosferatus
 +
* Smarbombs
 +
* Reactive armor hardener
 +
* Target spectrum breaker
 +
 
 +
[[Category:Fitting]]
 +
[[Category:Game mechanics]]
  
# [http://wiki.eveonline.com/en/wiki/Damage_Control_II Damage Control] modules and the [http://wiki.eveonline.com/en/wiki/Reactive_Armor_Hardener Reactive Armor Hardener] module work slightly differently. <p>If you only fit one or the other (one Damage Control ''or'' one Reactive Hardener), then they are ''never'' stacking penalized. They will ''always'' give their full damage resistance effect, along with your most effective module that also gives it's full effect as explained above, followed by any other modules that will be stacking penalized. This is one reason why the Damage Control module is so popular; because it is always 100% effective. </p><p>If, however, you fit ''both'', then one of them (whichever is less effective) will count as a second module and be stacking penalized accordingly (so, 86.9% effective).  This is in addition to your normal resistance modules, of which one will give its full effect and the rest stacking penalized as explained above. </p><p>As an example, consider the following five modules all fitted to your ship and their resulting effectiveness:  one Damage Control ''(100% effective)'', and one Reactive Armor Hardener ''(86.9% effective)''; one Armor EM Hardener ''(100% effective)'', one Energized Adaptive Nano Membrane ''(EM resistance 86.9% effective, other resistances 100% effective)'', and one Adaptive Nano Plating ''(EM resistance 57.1% effective, other resistances 86.9% effective)''.</p><p>Side note: armor/shield resistance bonuses gained from the relevant [[Fleet_Leadership#Warfare_Link_Skills_.26_Modules|warfare link modules]] are stacking penalized as normal, along with the rest of your resistance modules.
 
# The probe scan strength from Gravity Capacitor Upgrade rigs and Scan Rangefinding Arrays and Sisters & T2 launchers are all stacking penalized, even though the rigs & launchers don't mention it. Sisters probes are not, because they are not percentage effects - the core probes have a base strength of 11 instead of 10 (or 44 instead of 40 in the case of Sisters combat probes).
 
# Although the Nanobot Accelerator rig (to decrease armor repairer cycle time) says it is stacking penalized in Show Info, it isn't.
 
# Turret tracking speed modules are stacking penalized separately to turret tracking speed rigs (NOTE: this may no longer be true, requires testing).
 
  
There may be more weird exceptions that can be added here...
+
=== Weird Exceptions ===
  
== See also ==
+
<references />
* [[Module Stacking and Speed Modules]].
 
  
[[Category:PvP]]
+
[[Category:Fitting]]
[[Category:PvE]]
+
[[Category:Game mechanics]]
[[Category:Ship Fitting]]
 

Latest revision as of 11:50, 18 January 2020

Stacking penalties refer to an effectiveness reduction that is incurred when using two or more modules or rigs that affect the same attribute. The more modules or rigs affect the same attribute, the less effective each additional module is; in practice, having more than three or four modules/rigs affecting the same attribute is not worth it.

Most (but not all) modules and rigs will show in their description if they are subject to stacking penalties.

Note that it is the stat bonus that is affected, not the module itself. For example, if you fit both a Nanofiber Internal Structure (boosts agility and velocity) and an Overdrive Injector System (boosts velocity), the Nanofiber's velocity bonus would suffer a stacking penalty, but not its agility bonus. Similarly with armour or shield resistance modules: if you fit an EM hardener, an explosive hardener and an omni-hardener (Adaptive Invulnerability Field or Adaptive Nano Plating): the EM/Explosive resistances from the omni-hardener would be stacking-penalized but the Kinetic/Thermal resistances would not.

Also of note is that module drawbacks (negative effects) can also be stacking penalized.

Effects of stacking penalities

Normally, the benefits of additional modules/rigs would be multiplicative. So if fitting one Speed Booster (a fictional module with nice round numbers to make the math easier to understand) module increases a ship's speed by 10%, fitting two of them would increase a ship's speed by 21% ((1 + 10%) × (1 + 10%) = 1.1 × 1.1 = 1.21), and fitting three would increase it by 33% (1.1 × 1.1 × 1.1 = 1.33).

However, due to the stacking penalties effect, the second, third, and fourth Speed Booster modules' effects are only partially effective (86.9%, 57.1%, and 28.3% respectively - see below for details), and would therefore only increase a ship's speed by:

  • 10% × 86.9% = 9% for the second module
  • 10% × 57.1% = 5.7% for the third module
  • 10% × 28.3% = 2.8% for the fourth module

Therefore, the actual speed increase for the ship would be:

  • One Speed Booster module: +10%
  • Two Speed Booster modules: (1 + 10%) × (1 + (10% × 86.9%)) = (1 + 10.5%) × (1 + 9%) = +19.8%
  • Three Speed Booster modules: (1 + 19.8%) × (1 + 5.7%) = +26.7%
  • Four Speed Booster modules: (1 + 26.7%) × (1 + 2.8%) = +30.3%

However, the modules' bonuses still multiply, so even if the percentage increase of each subsequent module decreases sharply, the absolute increase of each subsequent module drops off more slowly. If we take a ship with a nominal speed of 100 m/s:

  • Adding one Speed Booster module: 100 + 10% = 110 m/s, an increase of +10 m/s
  • Adding a second Speed Booster module: 110 m/s + 9% = 120 m/s, an additional increase of +10 m/s
  • Adding a third Speed Booster module: 120 m/s + 5.7% = 127 m/s, an additional increase of +7 m/s
  • Adding a fourth Speed Booster module: 127 m/s + 2.8% = 130 m/s, an additional increase of +3 m/s


The Formula

The effectiveness of stacking penalized modules polotted.

Stacking-penalized modifiers are applied one at a time, in descending order of strength.

The n-th modifier is multiplied by S(n-1), as follows:

[math] S(u) = e^{-(u / 2.67)^2} [/math]

The Numbers

The exact numbers for stacking penalties can be gained by the formula above, but here are some rounded guidelines for quick calculations that doesn't need to be precise:

  • 1st mod: 100.0% effectiveness
  • 2nd mod: ~86.9% effectiveness
  • 3rd mod: ~57.1% effectiveness
  • 4th mod: ~28.3% effectiveness
  • 5th mod: ~10.6% effectiveness
  • 6th mod: ~3.0% effectiveness

As is clear, stacking more than 3 or 4 modules or rigs - unless you really have nothing else at all that you could fit there - that affect the same stat is fairly pointless, as your benefit is so tiny.

What suffers stacking penalties?

  1. Absolute effects are never stacking-penalized, only percentage effects. That is to say, things like +1 warp core strength, +1000 structure HP, +15 m signature radius, +400 GJ capacitor are not stacking-penalized because they are not percentage (%) effects.
  2. Only modules, rigs, the effects of Command Bursts and enviromental effects of Abyssal Deadspace are stacking-penalized. Skills, ship bonuses from ship skills, implants, hardwirings, boosters (such as Synth Blue Pill, Strong X-Instinct, and others) and the effects of wormhole space are not stacking penalized.
  3. Negative and positive effects are stacking-penalized separately. So, one +% and one -% effect to an attribute suffers no penalties, whereas with two +% and two -% effects, one of each would only be 86.9% effective. An example might be velocity modifiers: if you have one Overdrive Injector System on your ship (to increase your speed) whilst at the same time being slowed by a single Stasis Webifier from an enemy ship - both velocity modifers are 100% effective. If you are then affected by second Stasis Webifier (from the same or another ship) that second web will be only 86.9% effective.

It can be hard to tell exactly what suffers stacking penalties and what does not. For instance, the Overdrive Injector System II gives +12.5% velocity at a cost of -20% cargo capacity, and the description claims it suffers stacking penalties. The velocity bonus is stacking-penalized, but the cargo drawback is actually not. Similarly, the Warp Core Stabilizer II gives you one extra warp core strength at a cost of -40% targeting range and -40% scan resolution. It doesn't mention stacking penalty in the description, but the drawbacks are actually stacking-penalized.

We can learn from this that it is not the module itself which determines whether its effects are stacking-penalized, but rather the attribute affected.

Assuming the attribute they affect is actually stacking penalized, Command Burst modules are stacking penalized as normal, along with the rest of your modules and rigs.

Here's a handy table of what ship effects are stacking-penalized and which aren't; there are some weird exceptions which are further discussed below the table. Remember, it is only percentage effects from modules/rigs that are penalized.

Is <insert attribute> stacking-penalized?

Ship attribute Stacking-penalized
Powergrid (including reduced-PG-need effects) no
CPU (including reduced-CPU-need effects) no
Cargo capacity no
Capacitor capacity no[1]
Capacitor recharge rate no
Energy Warfare resistance yes
Module capacitor use no
Shield recharge rate no
Shield / armor / hull hit points no[2]
Shield / armor / hull resistances yes[3]
Shield boost / armor repair bonus yes
Sensor strength yes
ECM jammer strength yes
Sensor dampener scan resolution dampening strength yes
Sensor dampener targeting range dampening strength no
Scan probe sensor strength yes[4]
Scan resolution yes
Targeting range yes
Signature radius yes
Velocity yes[5]
Inertia modifier (agility) yes
Mass yes
Duration (cycle time) bonuses (except weapons) no[6]
Missile launcher rate of fire yes
Missile damage yes
Missile explosion velocity yes
Missile explosion radius yes
Missile flight time yes
Missile velocity yes
Turret rate of fire yes
Turret damage modifier yes
Turret tracking speed yes
All optimal range (modules/turrets) yes
All falloff (modules/turrets) yes
Mining laser yield (including mining drone yield) no
Drone control range no
Drone damage yes
Salvaging probability no

Bonuses from overheating sometimes follow same stacking penalties as normal bonuses. But this is not always the case.

Overheated module (bonus) Stacking-penalized
shield/armor repairer (repair ammount) yes
Local/remote shield/armor repairer (cycle time) no
ECM strength bonus yes
Sensor dampener (range dampening strength) no
Sensor dampener (resolution dampening strength) yes
Guidance and tracking disruptors yes
Target painters no
Warp disruptors, Warp scramblers and Stasis webifiers yes
Afterburners and micro warp drives yes[7]
Turrets and missile launchers (damage bonus) no
Turrets and missile launchers (Rate of fire bonus ) no
Capacitor transmitters no

Many overheating bonuses are not stacking penalized simply due to the fact that there are no modules or effects that would modify the same stat as the overheat bonus.These modules are considered to be not stacking penalized until an efect that modifies same stat as the overheat bonus is released.
Modules with no overlaping effects:

  • Sensor boosters
  • Capacitor boosters
  • Tracking/guidance computers
  • omnidirectional tracking links
  • Hull repairers
  • Active hardeners
  • Energy neutralizers and nosferatus
  • Smarbombs
  • Reactive armor hardener
  • Target spectrum breaker


Weird Exceptions

  1. ^ Both the flat bonus from capacitor batteries and percentage bonus from micro warp drives and capacitor flux coils are unpenalized.
  2. ^ Both the flat bonuses and percentage bonuses are unpenalized.
  3. ^ Damage Control modules and the Reactive Armor Hardener module work slightly differently.

    If you only fit one or the other (one Damage Control or one Reactive Hardener), then they are never stacking penalized. They will always give their full damage resistance effect, along with your most effective module that also gives it's full effect as explained above, followed by any other modules that will be stacking penalized. This is one reason why the Damage Control module is so popular; because it is always 100% effective.

    If, however, you fit both, then one of them (whichever is less effective) will count as a second module and be stacking penalized accordingly (so, 86.9% effective). This is in addition to your normal resistance modules, of which one will give its full effect and the rest stacking penalized as explained above.

    As an example, consider the following five modules all fitted to your ship and their resulting effectiveness: one Damage Control (100% effective), and one Reactive Armor Hardener (86.9% effective); one Armor EM Hardener (100% effective), one Energized Adaptive Nano Membrane (EM resistance 86.9% effective, other resistances 100% effective), and one Adaptive Nano Plating (EM resistance 57.1% effective, other resistances 86.9% effective).

  4. ^ The probe scan strength from Gravity Capacitor Upgrade rigs and Scan Rangefinding Arrays and Sisters & Tech 2 launchers are all stacking penalized, even though the rigs and launchers don't mention it. Sisters probes are not, because they are not percentage effects - the core probes have a base strength of 44 instead of 40 (or 22 instead of 20 in the case of Sisters combat probes).
  5. ^ There are two different velocity bonuses, the Maximum Velocity Bonus (propulsion modules such as afterburners and microwarpdrives) and the Velocity Modifier (propulsion upgrade modules such as nanifibers, overdrives etc). They stack separately and thus a MWD doesn't change the stacking order for multiple propulsion upgrades.
  6. ^ Although the Nanobot Accelerator rig (to decrease armor repairer cycle time) says it is stacking penalized in Show Info, it isn't.
  7. ^ Stacking penalized with rapid deploymend command burst. Not with speed boosting modules or rigs.