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Old 11-08-2022, 06:28 AM
Torven
Sarnak
 
Join Date: Aug 2014
Posts: 52
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How can we improve our drop tables now that we know how Sony's system works? I have a couple of examples.

In 2017 Ngreth posted a changelog for the item Obsidianwood Sap, which shows the current frequency, die size and item percent. The item table/list also includes a second item and the changelog shows the percentages for both. So we can know how the tables currently are and compare it to Magelo to get a better idea of Magelo's bias.

Quote:
Originally Posted by Ngreth
TIMESTAMP USER_NAME TRANSACTION_TYPE TABLE_NAME PK_VALUE MODIFIED_FIELD OLD_DATA NEW_DATA
17-Sep-02 <DEV2> INSERT tt 98113
17-Sep-02 <DEV2> UPDATE tt 98113 item_die_size 1 2
17-Oct-02 <DEV2> UPDATE tt 98113 item_frequency 45 40
03-Dec-02 <DEV3> UPDATE tt 98113 item_list_id 98113 981130
03-Dec-02 <DEV3> UPDATE tt 98113 item_list_id 981130 98113
17-Sep-02 <DEV2> INSERT it 98113
18-Sep-02 <DEV2> UPDATE it 98113 ITEM_2_NUM -1 15
18-Sep-02 <DEV2> UPDATE it 98113 ITEM_1_PERCENT 100 85
18-Sep-02 <DEV2> UPDATE it 98113 ITEM_2_PERCENT 0 10
18-Sep-02 <DEV2> UPDATE it 98113 ITEM_1_PERCENT 85 90
18-Sep-02 <DEV2> UPDATE it 98113 ITEM_2_NUM 15 29495
(source: https://forums.daybreakgames.com/eq/.../#post-3607870)

The treasure table item_frequency is 40%, meaning the NPC has a 40% chance to check the item table.
The treasure table item_die_size is 2, meaning it's 1d2 meaning it has one guaranteed drop if the frequency roll succeeds and a 50% chance for a second drop.
The item table has two items. The item ID is not shown but given the drop chance this drop has to be Fire Arachnid Silk.

Since the item table is 1d2, this means there should be a very small chance to get two saps from one mob. I checked old Al'Kabor logs for this and did find one case of somebody looting two saps within 1 second of each other which pretty much confirms it. Somebody could park a character in the zone with a merc to confirm this as well but I'm satisfied with the log I have.

Magelo drop rates for sap shows 5%, and for the silk 34%. Magelo rounds down for these drop percentiles, and manually calculating Magelo's data shows the drop rate about 5.5%. I've checked a lot of Magelo pages and I can say that Magelo often (but not always) has a negative bias for drops which is often around -5 to -10%, so this is pretty much as expected. This bias is clearly seen when checking drop rates for items that have a 100% drop chance but Magelo lists ~90-95%. Also Magelo counts all drops of multiples of an item as one. For silk the real drop rate (assuming my math is correct) should be 37.8%. (0.4*0.9 + 0.4*0.5*0.1*0.9) For sap the drop rate should be 5.8%. (0.4*0.1 + 0.4*0.5*0.9*0.1)

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Recently I improved the drop rates for some tradeskill items on TAKP. These items were Swirling Shadows and Shadeling Silk.

Swirling Shadows has a magelo drop rate of about 39% in Twilight Sea. I have some old AK logs of me farming these; I obtained about 2,000 of them and the average loot per kill was almost exactly 60%. Since these have a 1d2 item table die as they have a 50/50 chance to drop 1 or 2, this strongly implies a 40% chance frequency roll. It would make some sense for the Magelo bias to not be as bad there because the only reason to be there is to farm these things.

Shadeling Silk has a die size of 3, meaning 3 can drop from a kill. Magelo lists drop chances of 34% to 44% for this. I checked my old AK logs of me farming this. I killed 364 lesser shades which resulted in: 56 dropped one silk; 57 dropped 2 silks; 39 dropped 3 silks; 152 (41.7%) dropped one or more silks. I also killed 508 xakra larva which resulted in 419 shadeling silks. That is a loot per kill of 82.5%. A frequency roll of 40% with a 1d3 item die would result in a loot per kill rate of 80%. It actually makes some sense for Magelo's data to be less accurate here because with a larger die size comes more streakiness.

It's worth pointing out that often the higher drop rates on Magelo are from weaker NPCs, such is the case with Shadeling silk. This likely is the result of Sony copy and pasting the treasure tables along with the item tables for the NPCs and the lower level NPCs ending up higher due to margin of error. We can however see examples of Sony using different treasure tables for the same item table for tables of high level gems; i.e. Karnor's and City of Mist NPCs will not drop Fire Emeralds and such at the same rate as Plane of Fear NPCs even while using the same table.

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Since item tables must add up to 100% and Sony probably always used integers here, and presuming that Sony generally used multiples of 5 for frequency (it would be weird not to), this helps us improve the accuracy of drop tables.

There is an item table containing the Mithril Amulet item which drops items meant to be sold to vendors for money. By checking out multiple NPCs that drop Mithril Amulets we can see that the item table is:

Pearl Necklace, Fire Opal, Star Ruby, Fire Emerald, Sapphire, Emerald Ring, Opal Bracelet, Mithril Amulet

I added up all the drop percentiles for these items on several NPCs with a high drop chance for this table and the results were about 13-14%. It seems likely that Sony had a 15% frequency/probabiliy for this table for NPCs known to have dropped them commonly, such as planar mobs. (as mentioned above, some zones dropped these with a lower frequency)

We can attempt to get estimates for each individual item table drop percentile by dividing 1 by the sum of all of the table's drop chances and multiplying by the individual chance. Seafury Cyclopses in Ocean of Tears have the highest number of kills on Magelo, so that is the best NPC to look at:

a seafury cyclops; item table sum = 13.66%

Pearl Necklace 1.80% 13.14%
Fire Opal 1.97% 14.44%
Star Ruby 2.06% 15.08%
Fire Emerald 1.58% 11.58%
Sapphire 1.46% 10.69%
Emerald Ring 2.07% 15.13%
Opal Bracelet 1.42% 10.41%
Mithril Amulet 1.30% 9.52%

A lot of these values are close to either 10% or 15%. Sony's table may have used 10 and 15 values. The more valuable drops are the 10% values which makes this more plausible. Although Pearl Necklace and Fire Emerald are off by enough that those may have been different. I checked other tables and Fire Emerald was also significantly higher than 10% on those as well but randomness is notoriously streaky and narrowing down stuff to within one percent requires a LOT of trials, so some guesswork will always be required.

Incidentally I checked the Ruby Crown table as well and those are uniform at around 11% each.
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