Originally by: Drallimer

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So far nobody has been able to answer me this question.

This toon is specialized in ECM. With my skills I get 150km optimal + 100km falloff range with racial jammers in a Scorpion. Since transversal speed and tracking speed is irrelevant for ECM it leaves us the with the following formula:

C = 0.5^((R-O)/F)^2 where C = chance to hit, R = target range, O = optimal for weapon, F = falloff increment

This formula is quoted everywhere, including on this forum.

Now, the problem is....when you type in my values and a target range of 250km you get an inaccurate response from the formula: 0.25 = 0.5^((250km-150km)/100km)^2
We all know that optimal + falloff should yield 50% chance to hit, this formula does not. It is therefore, in my opinion, inaccurate.

Anyone have an accurate formula?

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Originally by: Furb Killer

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That would then be a fairly enormous error in ISK the guide.

Anyway @ OP, you got your brackets wrong, the square should be inside the exponential:
C = 0.5^(((R-O)/F)^2), then the result should be 0.5.

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Originally by: Ben Alman

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Quick go tell them we don't want people to die stupid :)

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Quote:

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http://fooplot.com/index.php?&type0=0&type1=0&type2=0&type3=0&type4=0&y0=0.5^%28%28%28x-10%29/5%29^2%29&y1=1-%28x-10%29/%285*2%29&y2=%280.5^%28%28%28x-10%29/5%29^2%29%29-%281-%28x-10%29/%285*2%29%29&y3=&y4=&r0=&r1=&r2=&r3=&r4=&px0=&px1=&px2=&px3=&px4=&py0=&py1=&py2=&py3=&py4=&smin0=0&smin1=0&smin2=0&smin3=0&smin4=0&smax0=2pi&smax1=2pi&smax2=2pi&smax3=2pi&smax4=2pi&thetamin0=0&thetamin1=0&thetamin2=0&thetamin3=0&thetamin4=0&thetamax0=2pi&thetamax1=2pi&thetamax2=2pi&thetamax3=2pi&thetamax4=2pi&ipw=1&ixmin=10&ixmax=20&iymin=-0.1&iymax=1&igx=1&igy=0.1&igl=1&igs=0&iax=1&ila=1&xmin=10&xmax=20&ymin=-0.1&ymax=1

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