User:Qiff/random math

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On this page I will try to explain some of the math and the statistics behind certain processes that are based on chance and occur randomly. If I'm wrong, please correct me on the talk page.

Note: some examples use Black Lion Trading Post prices. These will not be updated in this post. For the actual price, check the TP in-game.

An MMO lives on randomly generated processes and is a vital piece of the economic puzzle. And while I'm no economic genious, I do know something about math. In this article I will discuss a few of these processes and how the player can influence them.


Do not sell all your materials on the TP[edit]

Example: There you are, farming Orr for a while, finding some nice Vials of Powerful Blood, which are worth quite some money (about 31s now), and which you sell to build up your cash pile. Then, for some reason, you want to get a legendary weapon. Now it is time to buy all your vials back, because you need 250 of those nasty things.

At this point, assuming the price of vials stays the same*, you have lost 15% of income (due to the trading post fee) and have to farm that extra 15% of money to buy your vials back.

The math: You have sold 100 vials for 31s a piece, which gets you 31*100*0,85=2635=26g35s. Later, when deciding you need a legendary, you essentially have to buy back your own vials, for 31g / 100 vials. You only have 26g, so you need 5g more to buy your own vials back. This means that you have to farm 15% more gold.

The other way around works the same. You have bought 250 vials, so you're done with that part of the legendary weapon, and continue to farm Orr. Every vial you get is not needed and can be sold. But you have to pay that 15% fee again and therefore lose some money every time you sell one. You could have not sold those stack of vials and farmed your vials first. When you're done farming and have enough gold, you can buy the last batch of your vials to fill up that stack.

This does not work in every situation. It only works on the same materials and assumes prices on the TP stay the same. If you're good at price-watching and sell the vials at high prices and buy them at lower prices (at least 15% lower of course), the above situation does not apply to you (and I congratulate you for the patience of watching prices all day). It also does not work for different materials. If you have 250 powerful venom sacs, but need a few more vials, you can of course sell your leftover sacs and use that money to buy your vials.

Transmuting in the Mystic Forge[edit]

Materials (including lodestones) can be thrown into the Mystic Forge to upgrade them to a higher tier.

Example: You need 100 Charged Lodestones for a legendary gift (poor you) and farm CoE for them. You keep the lodestones and sell the cores. You are losing more money than needed. The math here is the same as in the example above. Assume the cores are worth 1g and the lodestones 3g. Making 1 lodestone requires:

  • 2 cores (2g)
  • 1 crystalline dust (25s)
  • 1 Bottle of Elonian wine (25,6s)
  • 1 crystal (0g)

Math: The cores cost 1g, but when you have farmed them yourself and sell them, you only get 85s for them. This should be taken into account when transmuting items in the MF. The same goes for the dust, but the 15% here does not matter as much as with the cores. The value of the recipe above is lower than the buying price of 1 lodestone (85*2+25+25,6=2,2g), so it is better to transmute your cores than to sell it.

Always calculate the recipe value based on the prices that affect you, so the price on the TP (if you have to buy them) or the profit you make from selling them. If you are transmuting t5 materials into t6 ones, they can have varying results (e.g. the recipe for vials of powerful blood can give you 5-12 vials). If there is a droprate research going on, take the average outcome of the recipe and calculate with that.

Precursors from the Mystic Forge[edit]

I wanted Sunrise for my Asuran Warrior. While I do play a lot (1-2 hrs a day, 4-8 hrs a day in weekends) I had a hard time saving 650g to buy Dawn. I tried the Mystic Forge, which is a gamble, which I hate. I love RNG things in games, but gambling money is never a viable option. Luck is a concept created by human beings, but it is not a law. It does not exist as supernatural force. Gambling games are always programmed in such a way that the bank in the long run always wins. The Mystic Forge is not really a 'bank,' but is designed as a sink, to drain excess money out of the economy. The problem with precursors, however, is that they are too rare (Arenanet confirmed this was a problem in a forum post and they will look into it). At the time of starting this article, there was not a single Hunter for sale. This makes the prices very unstable. With this in mind, I tried the Mystic Forge. It had some advantages over buying Dawn from the TP:

  • You do not need to save 650g at once. I did with 200g tries.
  • While it is random, popular precursors were never meant to be this pricy (confirmed in forum post). I believe that the average chance of getting a precursor from the Forge should then be higher than the money needed to buy Dawn from the TP.

It has one big con, though:

  • You never know when you get it. Could be before you even threw 40 weapons in, could be after 1500.

The problem with my precursor is that its popularity makes prices of rare greatswords and the TP rise. Therefore it was more viable for me to craft my own Greatswords. Note: Always check the TP prices of available weapons and materials and calculate the difference. I think the best way to use the Mystic Forge to get your precursor is to buy/craft (depending on price) level 80 rare Greatswords. I think exotics are too expensive to throw in. Use your rare greatswords in the 'Mystic Toilet,' and sell the exotics you get. For greatswords, this got me ~70g back from 180g I threw in. This saves quite some money. After about 250g worth of greatswords, I got Dawn. I got 'lucky', which saved me 400g. I always kept in mind, though, that it was a random process and it might fail. I figured i'd try to get it up to 600g. After that it should not be worth it and I would just have had to farm 650g.

Update: On the official forum, a guy posted his results of forging a lot of precursors. Statistics are more powerful the higher the repeats in your experiment, and this guy finally had some numbers on the average chance of a lvl 80 rare giving a precursor. From his calculations at that time I could conclude that generating a precursor with lvl 80 rares costs about 250g. It seems I was correct in assuming that 600g is way too much for a precursor. Furthermore I have tried the forge a few times again and got Zap for ~100g, Colossus for ~10g and another Dawn for ~120g. Prices of materials used to craft the rares have gone up lately, suggesting that more people are trying the Mystic Forge nowadays.

Salvaging Ectos[edit]

Globs of Ectoplasm are just as popular in GW2 as they were in GW1. In GW1, they were used as a currency besides gold, to pay for items that exceeded the 100k gold limit (different money system than GW2) and were used to craft the most expensive armor in the game, Obsidian Armor. In this game, they are used for just about anything at high levels. They are commonly aquired by salvaging high level gear, mostly rare items. I have seen people make an aweful lot of mistakes when it comes to ecto salvaging.

The Math: any rare/exotic gear piece of level 68 and higher has a chance of recieving 0 to 3 ectos. According to the forum post linked on the Ecto page, a Master's Salvage Kit produces and average 0,90 ectos/use. This means that if you salvage 20 level 80 rare weapons, you get an average of 18 ectos. The 1,25 ectos/use from the Black Lion Salvage Kit results in 25 ectos from those 20 rares. Exotics were not really worth it to salvage for ectos, especially with a Masters Kit. Most exotics are worth far more than the maximum ectos you can get (everything above ~2g will not generate a profit with ectos and should be sold). Sometimes, the rune/sigil on the exotic item is worth almost just as much as the whole item. Try to salvage that with a Black Lion Kit, to make sure you get the sigil/rune to sell. This way, the ectos you get are your extra profit, while the sigil/rune compensates for the item price. I do not think it is worth buying those items and selling the components for two reasons. 1. If it works, other people do/have done it already and the prices will even out. 2. Don't forget you have that 15% selling fee.

So which rares should you salvage and which ones should you sell? Assuming I use a Master's Kit, my general rule is: if my profit (after selling fee) from selling the item is higher than the ecto price, I sell. If the ecto price is 22s, and my level 80 rare dagger sells for 31s, I sell the dagger. Daggers and Greatswords are almost always more worth when sold, because of people using them for the Mystic Forge to get the more popular legendaries. Rare runes are worth 4-5s when sold on the TP, which is not a lot, but could be taken into account when calculating the best profit. You could also use them in the Forge and hope for a superior and much pricier rune. One advantage of salvaging weapons is a chance of getting an Orichalcum Ore or Ancient Wood Log.

A Black Lion Kit is much better, but also much more expensive. I tend to use them for Exotic pieces (which I have to salvage) only. Still want to use them for your every day rares? Keep in mind that every kit costs 300 gems (is almost 30g at the time of writing) and every use is ~24s. Generally, your dailies should provide you with enough BL kits to salvage your exotics.