Electronic warfare resistance and remote assistance impedance are a class of attributes that reduce the effectiveness of electronic warfare and remote assistance modules. They comes in many shapes and forms, some through innate ship bonuses or tactical modes, others through special modules.
Resistances and impedances
On a basic level, the difference between resistances and impedances is that:
- Resistances help you by making hostile effects (such as electronic warfare) less effective
- Impedances make friendly effects (such as remote assistance) less effective.
There are a variety of attributes that affects the effectiveness of electronic warfare and remote assistance.
| Type | Attribute | Effect |
|---|---|---|
| Electronic warfare |  Sensor Dampener Resistance Sensor Warfare Resistance [1]
|
Reduces the effect of hostile  Remote Sensor Dampeners.
|
| Remote assistance | Remote Assistance Impedance [2] Remote Electronic Assistance Impedance
|
Reduces the effect of Remote Sensor Boosters and  Remote Tracking Computers.
|
| Electronic warfare |  Weapon Disruption Resistance
|
Reduces the penalty from Weapon Disruption [3].
|
| Remote assistance |  Remote Repair Impedance Remote Logistics Impedance
|
Reduces the repaired amount from  Remote Hull Repairs, Remote Armor Repairs and  Remote Shield Boosters.
|
| Electronic warfare |  ECM Resistance
|
Additional chance to avoid being affected by ECM Jamming [4]
|
| Electronic warfare |  Stasis Webifier Resistance
|
Reduces the slowdown effect of hostile  Stasis Webifiers.
|
| Command Burst |  Electronic Hardening
|
Reduces the effect of hostile Remote Sensor Dampeners and Weapon Disruption [3].
|
| Electronic warfare |  Capacitor Warfare Resistance
|
Reduces the capacitor drained by hostile  Energy Neutralizers and  Energy Vampires.
|
Examples
Below are some examples of ships, modules or scripts with such resistances and impedances:
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Understanding the values
As with many attributes or bonuses, it can sometimes be difficult to understand how their effects are calculated. Sometimes attributes that are very similar in name, have the same functions, sometimes they do not. Sometimes the same type of effect can be shown as both a positive or a negative bonus, while functioning the same in the end.
Resistances
Resistances are often presented as negative bonus values, ranging from -0 down to -100%. The value represents how much of the effect is removed, so a -70% resistance bonus reduces the effectiveness of electronic warfare by 70%. This attribute can sometimes be presented as a positive bonus value (for example in the traits tab of a tactical destroyer). The bonus works the same though, despite it being a positive number, in that the +66.6% resistance bonus reduces electronic warfare effectiveness (in this case, weapon disruption and sensor dampening) by 66.6%.
ECM Resistance
ECM Resistance works differently from other electronic warfare resistances, in that they give a chance at avoiding the effect of enemy ECM jammers. This can best be explained as a flat "chance to fail" that is checked before anything else. This is an exception to how all the other resistances work due to the fact that a ship cannot be partially jammed. An 
ECM Resistance bonus of 100% means they cannot be jammed at all; the ECM module will simply not activate on the target. This can be a useful method in PvP to verify that a certain ship has entered triage or siege mode. A partial bonus of 50% would first roll the 50% chance of simply resisting the jamming effect right away, failing that it would then proceed to check whether the ECM strength of the hostile jammer is enough to overcome the sensor strength of the target.
Worth noting is that partial ECM resistance is currently a theoretical scenario described in the Reworking Capital Ships: And thus it begins! devblog; there are currently no such semi-resistance bonuses in the game, just 100% bonuses giving full immunity through Siege, Triage and Bastion modules.
Impedances
Impedances are also presented as either positive bonuses (often in the case for ships' innate impedance values) or negative bonuses (commonly done for impedance bonuses from modules). If the value is a negative value, like a -60% impedance bonus, it means that any incoming remote assistance of that kind is reduced by 60%. If the value is a positive +80% impedance bonus it means that they will lose 80% of the positive effect of the remote assistance, in effect only gaining 20% of it.