Make rank more random

backend/clubs/management/commands/rank.py

@@ -1,8 +1,8 @@
 import datetime
-import random
 from math import floor
 
 import bleach
+import numpy as np
 from django.core.management.base import BaseCommand
 from django.utils import timezone
 
@@ -220,8 +220,11 @@ def rank(self):
             if num_testimonials >= 3:
                 ranking += 5
 
-            # rng
-            ranking += random.random() * 10
+            # random number, mostly shuffles similar clubs with average of 15 points
+            # but with long right tail to periodically feature less popular clubs
+            # given ~700 active clubs, multiplier c, expected # clubs with rand > cd
+            # is 257, 95, 35, 13, 5, 2, 1 for c = 1, 2, 3, 4, 5, 6, 7
+            ranking += np.random.standard_exponential() * 15
 
             club.rank = floor(ranking)
             club.skip_history_when_saving = True

frontend/pages/rank.tsx

@@ -291,7 +291,10 @@ const Rank = (): ReactElement => (
           name: 'Random Factor',
           description: `A random factor is applied periodically in order to ensure that students see new ${OBJECT_NAME_PLURAL} when they visit ${SITE_NAME}.`,
           points: [
-            [10, 'Random number between 0 and this number, updated daily'],
+            [
+              15,
+              'Standard exponential random number scaled to average this number, updated daily',
+            ],
           ],
         },
       ]}