Remove randomness from country package

changelog_entry.yaml

@@ -0,0 +1,4 @@
+- bump: minor
+  changes:
+    changed:
+      - Remove randomness from country package by moving stochastic variable generation to data package. Variables now read pre-computed values from datasets for deterministic, reproducible calculations.

policyengine_uk/parameters/gov/social_security_scotland/scottish_child_payment/amount.yaml

@@ -11,7 +11,7 @@ metadata:
   period: week
   label: Scottish Child Payment weekly amount
   reference:
+    - title: The Scottish Child Payment Regulations 2020, Regulation 20
+      href: https://www.legislation.gov.uk/ssi/2020/351/regulation/20
     - title: Scottish Government - Scottish Child Payment
       href: https://www.gov.scot/policies/social-security/scottish-child-payment/
-    - title: Social Security Scotland - SCP statistics
-      href: https://www.socialsecurity.gov.scot/publications/2024/02/scottish-child-payment-statistics-to-31-december-2023

policyengine_uk/parameters/gov/social_security_scotland/scottish_child_payment/max_age.yaml

@@ -8,5 +8,7 @@ metadata:
   period: year
   label: Scottish Child Payment maximum age
   reference:
+    - title: The Scottish Child Payment Regulations 2020, Regulation 18
+      href: https://www.legislation.gov.uk/ssi/2020/351/regulation/18
     - title: Scottish Government - Scottish Child Payment
       href: https://www.gov.scot/policies/social-security/scottish-child-payment/

policyengine_uk/tests/policy/baseline/gov/social_security_scotland/scottish_child_payment.yaml

@@ -1,5 +1,6 @@
 # Scottish Child Payment tests
 # SCP available from Feb 2021, extended to under-16s from Nov 2022
+# scottish_child_payment is a Person-level variable
 
 - name: SCP for family receiving UC in Scotland (2024)
   period: 2024
@@ -21,8 +22,11 @@
         members: [parent, child_1, child_2]
         region: SCOTLAND
   output:
-    # £26.70/week * 52 weeks * 2 children = £2,776.80
-    scottish_child_payment: 2777
+    # £26.70/week * 52 weeks = £1,388.40 per child
+    scottish_child_payment:
+      parent: 0
+      child_1: 1388
+      child_2: 1388
 
 - name: SCP for family receiving UC in Scotland (2023)
   period: 2023
@@ -44,8 +48,11 @@
         members: [parent, child_1, child_2]
         region: SCOTLAND
   output:
-    # £25/week * 52 weeks * 2 children = £2,600
-    scottish_child_payment: 2600
+    # £25/week * 52 weeks = £1,300 per child
+    scottish_child_payment:
+      parent: 0
+      child_1: 1300
+      child_2: 1300
 
 - name: No SCP for families not receiving qualifying benefit
   period: 2024
@@ -66,7 +73,9 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    scottish_child_payment: 0
+    scottish_child_payment:
+      parent: 0
+      child_1: 0
 
 - name: No SCP in England
   period: 2024
@@ -86,7 +95,9 @@
         members: [parent, child_1]
         region: NORTH_EAST
   output:
-    scottish_child_payment: 0
+    scottish_child_payment:
+      parent: 0
+      child_1: 0
 
 - name: No SCP in Wales
   period: 2024
@@ -106,7 +117,9 @@
         members: [parent, child_1]
         region: WALES
   output:
-    scottish_child_payment: 0
+    scottish_child_payment:
+      parent: 0
+      child_1: 0
 
 - name: SCP before Nov 2022 only for under-6s
   period: 2022
@@ -129,7 +142,10 @@
         region: SCOTLAND
   output:
     # Only child_young (age 4) eligible, £20/week * 52 = £1,040
-    scottish_child_payment: 1040
+    scottish_child_payment:
+      parent: 0
+      child_young: 1040
+      child_older: 0
 
 - name: SCP for family receiving Child Tax Credit (2023 - CTC still qualifies)
   period: 2023
@@ -149,8 +165,10 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    # £25/week * 52 weeks * 1 child = £1,300
-    scottish_child_payment: 1300
+    # £25/week * 52 weeks = £1,300
+    scottish_child_payment:
+      parent: 0
+      child_1: 1300
 
 - name: No SCP before Feb 2021
   period: 2020
@@ -170,7 +188,9 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    scottish_child_payment: 0
+    scottish_child_payment:
+      parent: 0
+      child_1: 0
 
 - name: No SCP for child over 16
   period: 2024
@@ -190,7 +210,9 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    scottish_child_payment: 0
+    scottish_child_payment:
+      parent: 0
+      child_1: 0
 
 - name: Large family with multiple eligible children
   period: 2024
@@ -216,8 +238,13 @@
         members: [parent, child_1, child_2, child_3, child_4]
         region: SCOTLAND
   output:
-    # £26.70/week * 52 weeks * 4 children = £5,553.60
-    scottish_child_payment: 5554
+    # £26.70/week * 52 weeks = £1,388.40 per child
+    scottish_child_payment:
+      parent: 0
+      child_1: 1388
+      child_2: 1388
+      child_3: 1388
+      child_4: 1388
 
 # New tests for 2025 amount and qualifying benefit changes
 
@@ -239,8 +266,10 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    # £27.15/week * 52 weeks * 1 child = £1,411.80
-    scottish_child_payment: 1412
+    # £27.15/week * 52 weeks = £1,411.80
+    scottish_child_payment:
+      parent: 0
+      child_1: 1412
 
 - name: CTC no longer qualifies from 2025 (after April 2024)
   period: 2025
@@ -262,7 +291,9 @@
         region: SCOTLAND
   output:
     # CTC removed as qualifying benefit from April 2024
-    scottish_child_payment: 0
+    scottish_child_payment:
+      parent: 0
+      child_1: 0
 
 - name: CTC still qualifies in 2023 (before April 2024)
   period: 2023
@@ -283,8 +314,10 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    # £25/week * 52 weeks * 1 child = £1,300
-    scottish_child_payment: 1300
+    # £25/week * 52 weeks = £1,300
+    scottish_child_payment:
+      parent: 0
+      child_1: 1300
 
 - name: WTC no longer qualifies from 2025
   period: 2025
@@ -306,7 +339,9 @@
         region: SCOTLAND
   output:
     # WTC removed as qualifying benefit from April 2024
-    scottish_child_payment: 0
+    scottish_child_payment:
+      parent: 0
+      child_1: 0
 
 - name: Income Support still qualifies in 2025
   period: 2025
@@ -327,8 +362,10 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    # £27.15/week * 52 weeks * 1 child = £1,411.80
-    scottish_child_payment: 1412
+    # £27.15/week * 52 weeks = £1,411.80
+    scottish_child_payment:
+      parent: 0
+      child_1: 1412
 
 - name: JSA income-based still qualifies in 2025
   period: 2025
@@ -349,8 +386,10 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    # £27.15/week * 52 weeks * 1 child = £1,411.80
-    scottish_child_payment: 1412
+    # £27.15/week * 52 weeks = £1,411.80
+    scottish_child_payment:
+      parent: 0
+      child_1: 1412
 
 - name: ESA income-related still qualifies in 2025
   period: 2025
@@ -371,8 +410,10 @@
         members: [parent, child_1]
         region: SCOTLAND
   output:
-    # £27.15/week * 52 weeks * 1 child = £1,411.80
-    scottish_child_payment: 1412
+    # £27.15/week * 52 weeks = £1,411.80
+    scottish_child_payment:
+      parent: 0
+      child_1: 1412
 
 - name: Pension Credit still qualifies in 2025
   period: 2025
@@ -393,5 +434,7 @@
         members: [grandparent, child_1]
         region: SCOTLAND
   output:
-    # £27.15/week * 52 weeks * 1 child = £1,411.80
-    scottish_child_payment: 1412
+    # £27.15/week * 52 weeks = £1,411.80
+    scottish_child_payment:
+      grandparent: 0
+      child_1: 1412