Theory behind a string of bad runs

MrSlayer

Jungle Guide

Join Date: Apr 2006

United Kingdom

Quit Whining And [PLAY]

Mo/

13 Apr 2008 at 09:13 - 1

So I just wanted to write a short post about the theory behind bad runs, or more importantly, lots of them in a row. This isn't a flame or an attack at people who have reported problems with farming runs, just an attempt at an explanation. I hope it will at least be useful to 1 person.

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Edit: to explain, "Rolling a die" is basically throwing a dice. Dice is the plural term, but you get the idea. If you don't know what a dice is, it's (usually) a cube with a number of dots on each side corresponding to a number. Opposite sides of a 6 sided die add up to 7. Still not with me? Well here's a nice little picture, courtesy of a google search

http://www.thinkport.org/microsites/...mages/Dice.jpg
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I've seen, both in game and on forums, people complaining about getting 3-5, 5-10, or 10+ bad runs in a row. This applies mostly to UW farming, and I have experienced this myself too.

Just because you have had a string of X bad runs in a row does not mean that Anet must have nerfed the farm. I'll try and explain, using the drop rates of Globs of Ectoplasm, since they are the biggest source of complaint.

Let us just assume here. I don't know the exact % chance of drop rate for an Ecto, so I'll just make one up. It drops fairly rarely, so let's use 2% as our chance of getting an ecto. I'm also going to totally ignore loot scaling because, as you probably know, it doesn't affect Rare Materials.

Before we continue, I'd like to clear up a common misconception:
A 2% chance to drop an ecto does NOT mean that, for every 100 Smite Crawlers you kill, you will get 2 Ectos.

Now lets set the scene. You're in the underworld running a W/Rt build. It's your first run, so you've only pulled one group of smites. In this group are 5 Smite Crawlers, and you're just that good that you pull it off without a problem, killing them all. To make it simple, we're going to call them A, B, C, D and Bob.

A has a 2% chance to drop an ecto. Do you get one? Well let's be fair...let's pretend we're rolling a die with 50 faces, only one of which, has a picture of an Ecto on it. The other 50 are money, Holy Rods, etc. If you get an ecto landing face-up on your die, then congratulations, A has dropped you an ecto. The probability of you getting that Ecto-side facing upwards, out of a whole 50, is slim (0.02 to be exact). And ouch. Tough luck kiddo, you just got a blue Holy Rod with an "Improved Sale Value" mod.

B is up next. Again, you roll your 50 sided die (because you know, the Smite run is unimportant, and you've now decided to stop for a second and roll dice around with the Reaper). This die roll is totally independent of the first. This means that, no matter what you just rolled, Ecto, gold Stormbow, whatever, this die roll has no reason to be the same or different. It may be easier to think of it by saying that you took 5 50-sided die with you into the UW, and you're rolling a seperate die for each Smite Crawler you kill. Again, sorry kiddo, no Ecto. But you did just get a r12 Gold Tactics shield to ID on your Mesmer later.

Now it's C's turn. Out comes your third die. You might know what's coming up here. You roll it, and wow! It's your lucky day! You got an ecto. Against the odds, you managed to roll the 50 sided die with the side you wanted landing face up. Again, as you can probably see, this is totally independent of the previous rolls. Pocket your Ecto, and let's roll again.

D didn't look very nice, and your die lands on Phantom Residue. You can scrape that off your nice shield later; surely someone out there will want Crawler Remains for something.

Finally, it's time to roll last your die and see what Bob has dropped you. Bob is a very unique Crawler, as you might have guessed. And low and behold, your fifth die lands on the ecto. I'd say you're having typical beginners luck, because I've never had the first group drop me 2 ectos. But let's look at how this is possible. You've rolled a die, independent of the other 4 (sorry for repeating myself guys) and got an ecto. Each Smite has a totally seperate "roll" for dropping an ecto, and this can lead in 3 directions; occasional ecto-drops/average run, lots of ecto-drops/good run, or no ecto-drops/bad run. Now I bet you wouldn't run over to guru, tab across to alliance chat, or scream in all capitals in ToA (apologies for stereotyping) "SOMEONE HAS NERFED THE SMITE RUN!" Why? Because it favoured you. Infact, I'd bet you'd whisper the poor guy who hasn't got any ectos in 17 runs and say "Hey, I just got 2 ectos on the first group lol! They didn't nerf the run"

Now you can apply this up for every group of smite crawlers down there. I don't know how loot-scaling will affect the idea of rolling a die, so you can just pretend that some of the 50-faces of the die are blank. I know, that's not how it works, but it might help you to think of it that way because you'll still have 1/50 sides being the one you want.

So yes, this means that it is possible to get every Smite Crawler dropping an ecto. But, and this is assuming there are 40 Smite's down there, the probability of this happening is 1.09951163 × 10^-68.

To those with no mathematical knowledge, that is 0.000000000000000000000000000000000000000000000000 00000000000000000019951163 (out of 1). So yeah, congratulations; if you make that happen, and pull off a 40-ecto run, you are probably the luckiest man/woman/other alive today. You can settle down, start your average family, have your 2.4 children, and live the rest of your life knowing that there is almost nobody else alive luckier than you

. Or as they say here on guru "Screens or it never happened."

So you could go through one run after another, getting the rolls you want, and walking away with 6 or 7 ecto after an hour of farming. Or you could have a couple of runs where you don't get that lucky side of the die, and you get nothing. And there is nothing in the game that is going to feel pity for you after you've had 16 of these bad runs and give you an ecto. Sadly.

I hope this post has cleared up some of the misconceptions of bad runs coming back to back. Constructive feedback is welcome. Flamers can go find some other thread to build their bonfires of idiocy in. And remember guys; try and trust Anet at least a little. They would most probably leave an update-message saying something along the lines of "Lowered drop rate of Glob of Ectoplasm from Smite Crawler, Mindblade Spectre, Bladed Aatxe". I mean sure, they might not, but like I said. Have a little faith.

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Sethellington and Masao raised an interesting point. Skinny Corpse and his brother did some experimentation into the theory that drops are assigned at the beginning of a zone, and they went on to prove this. It was a very interesting test, which you can read about here (credit to them on their work). But as Masao said, this doesn't affect the theory I have put forward here.

Quote:

...all of the drops are set upon entry of the explorable area.

By entering at the exact moment in time that another person does, you'll get the same drop table and thus each mob will drop the same as the corresponding mob in the other person's map.

Think of it as rolling all the dice at the beginning of the map, rather than when you kill the mob.