Update default alpha from 1/2 to 2/3

contracts/staking/contracts/src/sys/MixinParams.sol

@@ -92,13 +92,18 @@ contract MixinParams is
         _assertParamsNotInitialized();
 
         // Set up defaults.
-        // These cannot be set to variables, or we go over the stack variable limit.
+        uint256 _epochDurationInSeconds = 10 days;
+        uint32 _rewardDelegatedStakeWeight = (90 * PPM_DENOMINATOR) / 100;
+        uint256 _minimumPoolStake = 100 * MIN_TOKEN_VALUE;
+        uint32 _cobbDouglasAlphaNumerator = 2;
+        uint32 _cobbDouglasAlphaDenominator = 3;
+
         _setParams(
-            10 days,                       // epochDurationInSeconds
-            (90 * PPM_DENOMINATOR) / 100,  // rewardDelegatedStakeWeight
-            100 * MIN_TOKEN_VALUE,         // minimumPoolStake
-            1,                             // cobbDouglasAlphaNumerator
-            2                              // cobbDouglasAlphaDenominator
+            _epochDurationInSeconds,
+            _rewardDelegatedStakeWeight,
+            _minimumPoolStake,
+            _cobbDouglasAlphaNumerator,
+            _cobbDouglasAlphaDenominator
         );
     }
 

contracts/staking/test/utils/constants.ts

@@ -14,8 +14,8 @@ export const constants = {
         epochDurationInSeconds: new BigNumber(TEN_DAYS),
         rewardDelegatedStakeWeight: new BigNumber(PPM * 0.9),
         minimumPoolStake: new BigNumber(10).pow(testConstants.DUMMY_TOKEN_DECIMALS).times(100),
-        cobbDouglasAlphaNumerator: new BigNumber(1),
-        cobbDouglasAlphaDenominator: new BigNumber(2),
+        cobbDouglasAlphaNumerator: new BigNumber(2),
+        cobbDouglasAlphaDenominator: new BigNumber(3),
     },
     PPM,
 };