Analysis of how time of day influences different Pokemon Type spawns

Introduction

After receiving several reports of anecdotal evidence that Dark Pokemon spawn more during the evening hours of the day, we went on to investigate. Our goal was to answer the following questions:

  • Is there any correlation between particular Type spawns and current time of day?
  • How does the game use local time and does it use it for spawns?

This is the first installment in our analysis of a data set that contains 1.8 million spawns recorded from February 18 to February 22. You can download the data set and analyse it on your own here. 

Methodology and data set

For this research we’ve used a CSV file provided by a reddit user that manages a private tracker. For obvious reasons, we are not publishing the name of our source, but the entire data set is available on Github for results verification and reproduction.

In order to create these results we’ve used SQL queries, mostly pretty standard stuff: CTEs, GROUP BY, ORDER BY and LEFT JOIN. The data set is organised into three tables:

  • feb18 – contains spawn info (spawnId, pokeId, spawnTime)
  • types – contains Pokemon specie typing information
  • pokemon_types – contains generic Pokemon type descriptions

The spawns were aggregated by the hour (hh portion of DateTime) when they occurred. All times in the database are recorded as local server time.

IMPORTANT NOTE

The data in the data set is not normalized. This means that recorded values per hour depend on number of pings during that period. The provider of the data set did not specify if pings are organic from users or from automated bots. Thanks to j16sdiz for highlighting the problem on GitHub. We are investigating the issue and will update results here as soon as possible.

Results and discoveries

After analyzing and verifying the results, we were able to provide answers to all initial questions, with some rather surprising discoveries, especially in terms of popular

Is there any correlation between particular Pokemon Type spawns and time of day?

Yes, there is! According to our research, Pokemon Types fall into various “spawn patterns” in regards to “time of day”.

  • Types like DARK and GHOST spawn heavily during the night, starting at 20:00 and continuing to 02:00 (local time)
    • We found no connection with the in game visual Day/Night cycle
  • A majority of other types mainly fall into the “normal daily cycle”
    • “normal daily cycle” lasts from 10:00 to 20:00 (local time) and is similar for a number of types
  • Types in the third group, mostly featuring ICE and DRAGON, have low sample sizes and don’t seem to follow any observable spawn pattern

We’ve observed two curious phenomena, both which could be due to method of recording the spawns and are still a mystery:

  • spawn numbers drop off aggressively around 02:00 (local time)
  • spawn numbers are unusually high from 00:00 to 01:00 (local time)

How does the game use local time and does it use it for spawns?

As data suggests, the game servers use local time to generate spawns. 

Niantic’s server side orchestrates the spawns in regards to current local time in the players area. The in-app day and night cycle is cosmetic only and has no correlation to actual world spawns and encounters.

Visual Representations

Raw Data

Hour of day Bug Dark Dragon Electric Fairy Fighting Fire Flying Ghost Grass Ground Ice Normal Poison Psychic Rock Water Grand Total
0 17590 11008 60 791 3653 134 687 37924 989 1036 5513 42 9203 1503 1049 207 5339 96728
1 17299 10556 33 808 3558 124 653 36496 952 1045 5283 26 8986 1559 1002 193 5347 93920
2 16934 10896 39 775 3530 137 722 36406 934 1062 5481 36 8972 1510 1084 237 5135 93890
3 13874 8830 33 574 2888 115 569 29856 858 869 4329 28 7508 1200 821 161 4192 76705
4 12210 7860 28 521 2570 87 515 26346 713 720 3845 22 6430 1121 725 127 3684 67524
5 12747 7870 43 525 2726 91 470 27532 751 782 3977 28 6730 1161 773 133 3862 70201
6 13282 8628 43 627 2803 115 624 29290 746 831 4154 24 7365 1157 806 134 3990 74619
7 13342 8654 35 581 2930 126 532 29192 802 844 4178 24 7237 1192 808 132 4077 74686
8 13393 8590 31 665 2736 99 561 29542 720 786 4047 22 7249 1240 834 158 4145 74818
9 12552 6000 44 648 3130 155 640 25874 437 1027 4582 36 9780 1312 763 187 4365 71532
10 12142 4650 34 708 3297 145 638 24556 233 1166 4702 32 10846 1343 776 186 4580 70034
11 12261 5036 43 681 3407 156 634 24842 287 1226 4874 30 10812 1316 806 166 4475 71052
12 13733 5204 37 840 3817 223 690 26558 366 1269 5151 34 11448 1667 910 196 4889 77032
13 14635 5288 42 786 3911 197 699 27322 335 1335 5524 30 11321 1571 890 217 5094 79197
14 14667 5534 38 846 4060 193 764 27996 330 1366 5765 42 11911 1612 942 203 5379 81648
15 13705 5480 52 876 3784 237 812 27048 396 1260 5607 36 11622 1480 906 213 5010 78524
16 14683 5198 31 884 3937 207 730 26564 353 1319 5719 36 11138 1556 882 199 5010 78446
17 14372 5452 40 814 4055 220 745 27376 302 1339 5842 38 11138 1516 914 217 5141 79521
18 14549 5360 42 792 3896 202 744 27216 307 1276 5490 28 11257 1503 833 197 5169 78861
19 14574 6838 34 758 3667 181 628 29158 568 1222 5208 34 9931 1506 920 221 4846 80294
20 15346 9550 37 758 3231 110 655 32310 817 911 4927 52 7673 1346 903 164 4587 83377
21 15494 9486 36 639 3243 124 601 32206 793 893 4560 30 7796 1276 937 160 4519 82793
22 14900 9524 34 670 3371 136 587 32612 855 803 4694 34 7927 1267 1000 168 4637 83219
23 14487 9228 49 686 3002 117 621 31498 837 850 4516 28 7744 1351 837 173 4282 80306
Grand Total 342771 180720 938 17253 81202 3631 15521 705720 14681 25237 117968 772 222024 33265 21121 4349 111754 1898927