formatting

This commit is contained in:
mantikoros 2022-01-10 17:52:03 -06:00
parent df4ecb3fe2
commit 9a834526c0
13 changed files with 251 additions and 251 deletions

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@ -1,19 +1,19 @@
export const PHANTOM_ANTE = 200; export const PHANTOM_ANTE = 200
export const calcStartPool = (initialProbInt: number, ante?: number) => { export const calcStartPool = (initialProbInt: number, ante?: number) => {
const p = initialProbInt / 100.0; const p = initialProbInt / 100.0
const totalAnte = PHANTOM_ANTE + (ante || 0); const totalAnte = PHANTOM_ANTE + (ante || 0)
const poolYes = const poolYes =
p === 0.5 p === 0.5
? p * totalAnte ? p * totalAnte
: -(totalAnte * (-p + Math.sqrt((-1 + p) * -p))) / (-1 + 2 * p); : -(totalAnte * (-p + Math.sqrt((-1 + p) * -p))) / (-1 + 2 * p)
const poolNo = totalAnte - poolYes; const poolNo = totalAnte - poolYes
const f = PHANTOM_ANTE / totalAnte; const f = PHANTOM_ANTE / totalAnte
const startYes = f * poolYes; const startYes = f * poolYes
const startNo = f * poolNo; const startNo = f * poolNo
return { startYes, startNo, poolYes, poolNo }; return { startYes, startNo, poolYes, poolNo }
}; }

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@ -1,22 +1,22 @@
export type Bet = { export type Bet = {
id: string; id: string
userId: string; userId: string
contractId: string; contractId: string
amount: number; // bet size; negative if SELL bet amount: number // bet size; negative if SELL bet
outcome: "YES" | "NO"; outcome: 'YES' | 'NO'
shares: number; // dynamic parimutuel pool weight; negative if SELL bet shares: number // dynamic parimutuel pool weight; negative if SELL bet
probBefore: number; probBefore: number
probAfter: number; probAfter: number
sale?: { sale?: {
amount: number; // amount user makes from sale amount: number // amount user makes from sale
betId: string; // id of bet being sold betId: string // id of bet being sold
// TODO: add sale time? // TODO: add sale time?
}; }
isSold?: boolean; // true if this BUY bet has been sold isSold?: boolean // true if this BUY bet has been sold
createdTime: number; createdTime: number
}; }

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@ -1,140 +1,140 @@
import { Bet } from "./bet"; import { Bet } from './bet'
import { Contract } from "./contract"; import { Contract } from './contract'
import { FEES } from "./fees"; import { FEES } from './fees'
export const blah = () => 999; export const blah = () => 999
export const getProbability = (pool: { YES: number; NO: number }) => { export const getProbability = (pool: { YES: number; NO: number }) => {
const [yesPool, noPool] = [pool.YES, pool.NO]; const [yesPool, noPool] = [pool.YES, pool.NO]
const numerator = Math.pow(yesPool, 2); const numerator = Math.pow(yesPool, 2)
const denominator = Math.pow(yesPool, 2) + Math.pow(noPool, 2); const denominator = Math.pow(yesPool, 2) + Math.pow(noPool, 2)
return numerator / denominator; return numerator / denominator
}; }
export function getProbabilityAfterBet( export function getProbabilityAfterBet(
pool: { YES: number; NO: number }, pool: { YES: number; NO: number },
outcome: "YES" | "NO", outcome: 'YES' | 'NO',
bet: number bet: number
) { ) {
const [YES, NO] = [ const [YES, NO] = [
pool.YES + (outcome === "YES" ? bet : 0), pool.YES + (outcome === 'YES' ? bet : 0),
pool.NO + (outcome === "NO" ? bet : 0), pool.NO + (outcome === 'NO' ? bet : 0),
]; ]
return getProbability({ YES, NO }); return getProbability({ YES, NO })
} }
export function calculateShares( export function calculateShares(
pool: { YES: number; NO: number }, pool: { YES: number; NO: number },
bet: number, bet: number,
betChoice: "YES" | "NO" betChoice: 'YES' | 'NO'
) { ) {
const [yesPool, noPool] = [pool.YES, pool.NO]; const [yesPool, noPool] = [pool.YES, pool.NO]
return betChoice === "YES" return betChoice === 'YES'
? bet + (bet * noPool ** 2) / (yesPool ** 2 + bet * yesPool) ? bet + (bet * noPool ** 2) / (yesPool ** 2 + bet * yesPool)
: bet + (bet * yesPool ** 2) / (noPool ** 2 + bet * noPool); : bet + (bet * yesPool ** 2) / (noPool ** 2 + bet * noPool)
} }
export function calculatePayout( export function calculatePayout(
contract: Contract, contract: Contract,
bet: Bet, bet: Bet,
outcome: "YES" | "NO" | "CANCEL" | "MKT" outcome: 'YES' | 'NO' | 'CANCEL' | 'MKT'
) { ) {
const { amount, outcome: betOutcome, shares } = bet; const { amount, outcome: betOutcome, shares } = bet
if (outcome === "CANCEL") return amount; if (outcome === 'CANCEL') return amount
if (outcome === "MKT") return calculateMktPayout(contract, bet); if (outcome === 'MKT') return calculateMktPayout(contract, bet)
if (betOutcome !== outcome) return 0; if (betOutcome !== outcome) return 0
const { totalShares, totalBets } = contract; const { totalShares, totalBets } = contract
if (totalShares[outcome] === 0) return 0; if (totalShares[outcome] === 0) return 0
const startPool = contract.startPool.YES + contract.startPool.NO; const startPool = contract.startPool.YES + contract.startPool.NO
const truePool = contract.pool.YES + contract.pool.NO - startPool; const truePool = contract.pool.YES + contract.pool.NO - startPool
if (totalBets[outcome] >= truePool) if (totalBets[outcome] >= truePool)
return (amount / totalBets[outcome]) * truePool; return (amount / totalBets[outcome]) * truePool
const total = totalShares[outcome] - totalBets[outcome]; const total = totalShares[outcome] - totalBets[outcome]
const winningsPool = truePool - totalBets[outcome]; const winningsPool = truePool - totalBets[outcome]
return (1 - FEES) * (amount + ((shares - amount) / total) * winningsPool); return (1 - FEES) * (amount + ((shares - amount) / total) * winningsPool)
} }
export function calculatePayoutAfterCorrectBet(contract: Contract, bet: Bet) { export function calculatePayoutAfterCorrectBet(contract: Contract, bet: Bet) {
const { amount, outcome, shares } = bet; const { amount, outcome, shares } = bet
const { totalShares, totalBets } = contract; const { totalShares, totalBets } = contract
const startPool = contract.startPool.YES + contract.startPool.NO; const startPool = contract.startPool.YES + contract.startPool.NO
const truePool = amount + contract.pool.YES + contract.pool.NO - startPool; const truePool = amount + contract.pool.YES + contract.pool.NO - startPool
const totalBetsOutcome = totalBets[outcome] + amount; const totalBetsOutcome = totalBets[outcome] + amount
const totalSharesOutcome = totalShares[outcome] + shares; const totalSharesOutcome = totalShares[outcome] + shares
if (totalBetsOutcome >= truePool) if (totalBetsOutcome >= truePool)
return (amount / totalBetsOutcome) * truePool; return (amount / totalBetsOutcome) * truePool
const total = totalSharesOutcome - totalBetsOutcome; const total = totalSharesOutcome - totalBetsOutcome
const winningsPool = truePool - totalBetsOutcome; const winningsPool = truePool - totalBetsOutcome
return (1 - FEES) * (amount + ((shares - amount) / total) * winningsPool); return (1 - FEES) * (amount + ((shares - amount) / total) * winningsPool)
} }
function calculateMktPayout(contract: Contract, bet: Bet) { function calculateMktPayout(contract: Contract, bet: Bet) {
const p = const p =
contract.pool.YES ** 2 / (contract.pool.YES ** 2 + contract.pool.NO ** 2); contract.pool.YES ** 2 / (contract.pool.YES ** 2 + contract.pool.NO ** 2)
const weightedTotal = const weightedTotal =
p * contract.totalBets.YES + (1 - p) * contract.totalBets.NO; p * contract.totalBets.YES + (1 - p) * contract.totalBets.NO
const startPool = contract.startPool.YES + contract.startPool.NO; const startPool = contract.startPool.YES + contract.startPool.NO
const truePool = contract.pool.YES + contract.pool.NO - startPool; const truePool = contract.pool.YES + contract.pool.NO - startPool
const betP = bet.outcome === "YES" ? p : 1 - p; const betP = bet.outcome === 'YES' ? p : 1 - p
if (weightedTotal >= truePool) { if (weightedTotal >= truePool) {
return ((betP * bet.amount) / weightedTotal) * truePool; return ((betP * bet.amount) / weightedTotal) * truePool
} }
const winningsPool = truePool - weightedTotal; const winningsPool = truePool - weightedTotal
const weightedShareTotal = const weightedShareTotal =
p * (contract.totalShares.YES - contract.totalBets.YES) + p * (contract.totalShares.YES - contract.totalBets.YES) +
(1 - p) * (contract.totalShares.NO - contract.totalBets.NO); (1 - p) * (contract.totalShares.NO - contract.totalBets.NO)
return ( return (
(1 - FEES) * (1 - FEES) *
(betP * bet.amount + (betP * bet.amount +
((betP * (bet.shares - bet.amount)) / weightedShareTotal) * winningsPool) ((betP * (bet.shares - bet.amount)) / weightedShareTotal) * winningsPool)
); )
} }
export function resolvedPayout(contract: Contract, bet: Bet) { export function resolvedPayout(contract: Contract, bet: Bet) {
if (contract.resolution) if (contract.resolution)
return calculatePayout(contract, bet, contract.resolution); return calculatePayout(contract, bet, contract.resolution)
throw new Error("Contract was not resolved"); throw new Error('Contract was not resolved')
} }
export function currentValue(contract: Contract, bet: Bet) { export function currentValue(contract: Contract, bet: Bet) {
const prob = getProbability(contract.pool); const prob = getProbability(contract.pool)
const yesPayout = calculatePayout(contract, bet, "YES"); const yesPayout = calculatePayout(contract, bet, 'YES')
const noPayout = calculatePayout(contract, bet, "NO"); const noPayout = calculatePayout(contract, bet, 'NO')
return prob * yesPayout + (1 - prob) * noPayout; return prob * yesPayout + (1 - prob) * noPayout
} }
export function calculateSaleAmount(contract: Contract, bet: Bet) { export function calculateSaleAmount(contract: Contract, bet: Bet) {
const { shares, outcome } = bet; const { shares, outcome } = bet
const { YES: yesPool, NO: noPool } = contract.pool; const { YES: yesPool, NO: noPool } = contract.pool
const { YES: yesStart, NO: noStart } = contract.startPool; const { YES: yesStart, NO: noStart } = contract.startPool
const { YES: yesShares, NO: noShares } = contract.totalShares; const { YES: yesShares, NO: noShares } = contract.totalShares
const [y, n, s] = [yesPool, noPool, shares]; const [y, n, s] = [yesPool, noPool, shares]
const shareValue = const shareValue =
outcome === "YES" outcome === 'YES'
? // https://www.wolframalpha.com/input/?i=b+%2B+%28b+n%5E2%29%2F%28y+%28-b+%2B+y%29%29+%3D+c+solve+b ? // https://www.wolframalpha.com/input/?i=b+%2B+%28b+n%5E2%29%2F%28y+%28-b+%2B+y%29%29+%3D+c+solve+b
(n ** 2 + (n ** 2 +
s * y + s * y +
@ -149,18 +149,18 @@ export function calculateSaleAmount(contract: Contract, bet: Bet) {
Math.sqrt( Math.sqrt(
y ** 4 + (s - n) ** 2 * n ** 2 + 2 * y ** 2 * n * (s + n) y ** 4 + (s - n) ** 2 * n ** 2 + 2 * y ** 2 * n * (s + n)
)) / )) /
(2 * n); (2 * n)
const startPool = yesStart + noStart; const startPool = yesStart + noStart
const pool = yesPool + noPool - startPool; const pool = yesPool + noPool - startPool
const probBefore = yesPool ** 2 / (yesPool ** 2 + noPool ** 2); const probBefore = yesPool ** 2 / (yesPool ** 2 + noPool ** 2)
const f = pool / (probBefore * yesShares + (1 - probBefore) * noShares); const f = pool / (probBefore * yesShares + (1 - probBefore) * noShares)
const myPool = outcome === "YES" ? yesPool - yesStart : noPool - noStart; const myPool = outcome === 'YES' ? yesPool - yesStart : noPool - noStart
const adjShareValue = Math.min(Math.min(1, f) * shareValue, myPool); const adjShareValue = Math.min(Math.min(1, f) * shareValue, myPool)
const saleAmount = (1 - FEES) * adjShareValue; const saleAmount = (1 - FEES) * adjShareValue
return saleAmount; return saleAmount
} }

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@ -1,12 +1,12 @@
// Currently, comments are created after the bet, not atomically with the bet. // Currently, comments are created after the bet, not atomically with the bet.
// They're uniquely identified by the pair contractId/betId. // They're uniquely identified by the pair contractId/betId.
export type Comment = { export type Comment = {
contractId: string; contractId: string
betId: string; betId: string
text: string; text: string
createdTime: number; createdTime: number
// Denormalized, for rendering comments // Denormalized, for rendering comments
userName?: string; userName?: string
userUsername?: string; userUsername?: string
userAvatarUrl?: string; userAvatarUrl?: string
}; }

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@ -1,29 +1,29 @@
export type Contract = { export type Contract = {
id: string; id: string
slug: string; // auto-generated; must be unique slug: string // auto-generated; must be unique
creatorId: string; creatorId: string
creatorName: string; creatorName: string
creatorUsername: string; creatorUsername: string
question: string; question: string
description: string; // More info about what the contract is about description: string // More info about what the contract is about
outcomeType: "BINARY"; // | 'MULTI' | 'interval' | 'date' outcomeType: 'BINARY' // | 'MULTI' | 'interval' | 'date'
// outcomes: ['YES', 'NO'] // outcomes: ['YES', 'NO']
startPool: { YES: number; NO: number }; startPool: { YES: number; NO: number }
pool: { YES: number; NO: number }; pool: { YES: number; NO: number }
totalShares: { YES: number; NO: number }; totalShares: { YES: number; NO: number }
totalBets: { YES: number; NO: number }; totalBets: { YES: number; NO: number }
createdTime: number; // Milliseconds since epoch createdTime: number // Milliseconds since epoch
lastUpdatedTime: number; // If the question or description was changed lastUpdatedTime: number // If the question or description was changed
closeTime?: number; // When no more trading is allowed closeTime?: number // When no more trading is allowed
isResolved: boolean; isResolved: boolean
resolutionTime?: number; // When the contract creator resolved the market resolutionTime?: number // When the contract creator resolved the market
resolution?: "YES" | "NO" | "CANCEL"; // Chosen by creator; must be one of outcomes resolution?: 'YES' | 'NO' | 'CANCEL' // Chosen by creator; must be one of outcomes
volume24Hours: number; volume24Hours: number
volume7Days: number; volume7Days: number
}; }

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@ -1,4 +1,4 @@
export const PLATFORM_FEE = 0.01; // == 1% export const PLATFORM_FEE = 0.01 // == 1%
export const CREATOR_FEE = 0.01; export const CREATOR_FEE = 0.01
export const FEES = PLATFORM_FEE + CREATOR_FEE; export const FEES = PLATFORM_FEE + CREATOR_FEE

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@ -1,42 +1,42 @@
import { Bet } from "./bet"; import { Bet } from './bet'
import { Contract } from "./contract"; import { Contract } from './contract'
import { User } from "./user"; import { User } from './user'
export const getNewBetInfo = ( export const getNewBetInfo = (
user: User, user: User,
outcome: "YES" | "NO", outcome: 'YES' | 'NO',
amount: number, amount: number,
contract: Contract, contract: Contract,
newBetId: string newBetId: string
) => { ) => {
const { YES: yesPool, NO: noPool } = contract.pool; const { YES: yesPool, NO: noPool } = contract.pool
const newPool = const newPool =
outcome === "YES" outcome === 'YES'
? { YES: yesPool + amount, NO: noPool } ? { YES: yesPool + amount, NO: noPool }
: { YES: yesPool, NO: noPool + amount }; : { YES: yesPool, NO: noPool + amount }
const shares = const shares =
outcome === "YES" outcome === 'YES'
? amount + (amount * noPool ** 2) / (yesPool ** 2 + amount * yesPool) ? amount + (amount * noPool ** 2) / (yesPool ** 2 + amount * yesPool)
: amount + (amount * yesPool ** 2) / (noPool ** 2 + amount * noPool); : amount + (amount * yesPool ** 2) / (noPool ** 2 + amount * noPool)
const { YES: yesShares, NO: noShares } = contract.totalShares; const { YES: yesShares, NO: noShares } = contract.totalShares
const newTotalShares = const newTotalShares =
outcome === "YES" outcome === 'YES'
? { YES: yesShares + shares, NO: noShares } ? { YES: yesShares + shares, NO: noShares }
: { YES: yesShares, NO: noShares + shares }; : { YES: yesShares, NO: noShares + shares }
const { YES: yesBets, NO: noBets } = contract.totalBets; const { YES: yesBets, NO: noBets } = contract.totalBets
const newTotalBets = const newTotalBets =
outcome === "YES" outcome === 'YES'
? { YES: yesBets + amount, NO: noBets } ? { YES: yesBets + amount, NO: noBets }
: { YES: yesBets, NO: noBets + amount }; : { YES: yesBets, NO: noBets + amount }
const probBefore = yesPool ** 2 / (yesPool ** 2 + noPool ** 2); const probBefore = yesPool ** 2 / (yesPool ** 2 + noPool ** 2)
const probAfter = newPool.YES ** 2 / (newPool.YES ** 2 + newPool.NO ** 2); const probAfter = newPool.YES ** 2 / (newPool.YES ** 2 + newPool.NO ** 2)
const newBet: Bet = { const newBet: Bet = {
id: newBetId, id: newBetId,
@ -48,9 +48,9 @@ export const getNewBetInfo = (
probBefore, probBefore,
probAfter, probAfter,
createdTime: Date.now(), createdTime: Date.now(),
}; }
const newBalance = user.balance - amount; const newBalance = user.balance - amount
return { newBet, newPool, newTotalShares, newTotalBets, newBalance }; return { newBet, newPool, newTotalShares, newTotalBets, newBalance }
}; }

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@ -1,6 +1,6 @@
import { calcStartPool } from "./antes"; import { calcStartPool } from './antes'
import { Contract } from "./contract"; import { Contract } from './contract'
import { User } from "./user"; import { User } from './user'
export function getNewContract( export function getNewContract(
id: string, id: string,
@ -15,12 +15,12 @@ export function getNewContract(
const { startYes, startNo, poolYes, poolNo } = calcStartPool( const { startYes, startNo, poolYes, poolNo } = calcStartPool(
initialProb, initialProb,
ante ante
); )
const contract: Contract = { const contract: Contract = {
id, id,
slug, slug,
outcomeType: "BINARY", outcomeType: 'BINARY',
creatorId: creator.id, creatorId: creator.id,
creatorName: creator.name, creatorName: creator.name,
@ -40,9 +40,9 @@ export function getNewContract(
volume24Hours: 0, volume24Hours: 0,
volume7Days: 0, volume7Days: 0,
}; }
if (closeTime) contract.closeTime = closeTime; if (closeTime) contract.closeTime = closeTime
return contract; return contract
} }

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@ -1,17 +1,17 @@
import { Bet } from "./bet"; import { Bet } from './bet'
import { Contract } from "./contract"; import { Contract } from './contract'
import { CREATOR_FEE, FEES } from "./fees"; import { CREATOR_FEE, FEES } from './fees'
export const getCancelPayouts = (truePool: number, bets: Bet[]) => { export const getCancelPayouts = (truePool: number, bets: Bet[]) => {
console.log("resolved N/A, pool M$", truePool); console.log('resolved N/A, pool M$', truePool)
const betSum = sumBy(bets, (b) => b.amount); const betSum = sumBy(bets, (b) => b.amount)
return bets.map((bet) => ({ return bets.map((bet) => ({
userId: bet.userId, userId: bet.userId,
payout: (bet.amount / betSum) * truePool, payout: (bet.amount / betSum) * truePool,
})); }))
}; }
export const getStandardPayouts = ( export const getStandardPayouts = (
outcome: string, outcome: string,
@ -19,26 +19,26 @@ export const getStandardPayouts = (
contract: Contract, contract: Contract,
bets: Bet[] bets: Bet[]
) => { ) => {
const [yesBets, noBets] = partition(bets, (bet) => bet.outcome === "YES"); const [yesBets, noBets] = partition(bets, (bet) => bet.outcome === 'YES')
const winningBets = outcome === "YES" ? yesBets : noBets; const winningBets = outcome === 'YES' ? yesBets : noBets
const betSum = sumBy(winningBets, (b) => b.amount); const betSum = sumBy(winningBets, (b) => b.amount)
if (betSum >= truePool) return getCancelPayouts(truePool, winningBets); if (betSum >= truePool) return getCancelPayouts(truePool, winningBets)
const creatorPayout = CREATOR_FEE * truePool; const creatorPayout = CREATOR_FEE * truePool
console.log( console.log(
"resolved", 'resolved',
outcome, outcome,
"pool: M$", 'pool: M$',
truePool, truePool,
"creator fee: M$", 'creator fee: M$',
creatorPayout creatorPayout
); )
const shareDifferenceSum = sumBy(winningBets, (b) => b.shares - b.amount); const shareDifferenceSum = sumBy(winningBets, (b) => b.shares - b.amount)
const winningsPool = truePool - betSum; const winningsPool = truePool - betSum
const winnerPayouts = winningBets.map((bet) => ({ const winnerPayouts = winningBets.map((bet) => ({
userId: bet.userId, userId: bet.userId,
@ -46,12 +46,12 @@ export const getStandardPayouts = (
(1 - FEES) * (1 - FEES) *
(bet.amount + (bet.amount +
((bet.shares - bet.amount) / shareDifferenceSum) * winningsPool), ((bet.shares - bet.amount) / shareDifferenceSum) * winningsPool),
})); }))
return winnerPayouts.concat([ return winnerPayouts.concat([
{ userId: contract.creatorId, payout: creatorPayout }, { userId: contract.creatorId, payout: creatorPayout },
]); // add creator fee ]) // add creator fee
}; }
export const getMktPayouts = ( export const getMktPayouts = (
truePool: number, truePool: number,
@ -59,30 +59,30 @@ export const getMktPayouts = (
bets: Bet[] bets: Bet[]
) => { ) => {
const p = const p =
contract.pool.YES ** 2 / (contract.pool.YES ** 2 + contract.pool.NO ** 2); contract.pool.YES ** 2 / (contract.pool.YES ** 2 + contract.pool.NO ** 2)
console.log("Resolved MKT at p=", p, "pool: $M", truePool); console.log('Resolved MKT at p=', p, 'pool: $M', truePool)
const [yesBets, noBets] = partition(bets, (bet) => bet.outcome === "YES"); const [yesBets, noBets] = partition(bets, (bet) => bet.outcome === 'YES')
const weightedBetTotal = const weightedBetTotal =
p * sumBy(yesBets, (b) => b.amount) + p * sumBy(yesBets, (b) => b.amount) +
(1 - p) * sumBy(noBets, (b) => b.amount); (1 - p) * sumBy(noBets, (b) => b.amount)
if (weightedBetTotal >= truePool) { if (weightedBetTotal >= truePool) {
return bets.map((bet) => ({ return bets.map((bet) => ({
userId: bet.userId, userId: bet.userId,
payout: payout:
(((bet.outcome === "YES" ? p : 1 - p) * bet.amount) / (((bet.outcome === 'YES' ? p : 1 - p) * bet.amount) /
weightedBetTotal) * weightedBetTotal) *
truePool, truePool,
})); }))
} }
const winningsPool = truePool - weightedBetTotal; const winningsPool = truePool - weightedBetTotal
const weightedShareTotal = const weightedShareTotal =
p * sumBy(yesBets, (b) => b.shares - b.amount) + p * sumBy(yesBets, (b) => b.shares - b.amount) +
(1 - p) * sumBy(noBets, (b) => b.shares - b.amount); (1 - p) * sumBy(noBets, (b) => b.shares - b.amount)
const yesPayouts = yesBets.map((bet) => ({ const yesPayouts = yesBets.map((bet) => ({
userId: bet.userId, userId: bet.userId,
@ -90,7 +90,7 @@ export const getMktPayouts = (
(1 - FEES) * (1 - FEES) *
(p * bet.amount + (p * bet.amount +
((p * (bet.shares - bet.amount)) / weightedShareTotal) * winningsPool), ((p * (bet.shares - bet.amount)) / weightedShareTotal) * winningsPool),
})); }))
const noPayouts = noBets.map((bet) => ({ const noPayouts = noBets.map((bet) => ({
userId: bet.userId, userId: bet.userId,
@ -99,30 +99,30 @@ export const getMktPayouts = (
((1 - p) * bet.amount + ((1 - p) * bet.amount +
(((1 - p) * (bet.shares - bet.amount)) / weightedShareTotal) * (((1 - p) * (bet.shares - bet.amount)) / weightedShareTotal) *
winningsPool), winningsPool),
})); }))
const creatorPayout = CREATOR_FEE * truePool; const creatorPayout = CREATOR_FEE * truePool
return [ return [
...yesPayouts, ...yesPayouts,
...noPayouts, ...noPayouts,
{ userId: contract.creatorId, payout: creatorPayout }, { userId: contract.creatorId, payout: creatorPayout },
]; ]
}; }
const partition = <T>(array: T[], f: (t: T) => boolean) => { const partition = <T>(array: T[], f: (t: T) => boolean) => {
const yes = []; const yes = []
const no = []; const no = []
for (let t of array) { for (let t of array) {
if (f(t)) yes.push(t); if (f(t)) yes.push(t)
else no.push(t); else no.push(t)
} }
return [yes, no] as [T[], T[]]; return [yes, no] as [T[], T[]]
}; }
const sumBy = <T>(array: T[], f: (t: T) => number) => { const sumBy = <T>(array: T[], f: (t: T) => number) => {
const values = array.map(f); const values = array.map(f)
return values.reduce((prev, cur) => prev + cur, 0); return values.reduce((prev, cur) => prev + cur, 0)
}; }

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@ -1,7 +1,7 @@
import { Bet } from "./bet"; import { Bet } from './bet'
import { Contract } from "./contract"; import { Contract } from './contract'
import { CREATOR_FEE, PLATFORM_FEE } from "./fees"; import { CREATOR_FEE, PLATFORM_FEE } from './fees'
import { User } from "./user"; import { User } from './user'
export const getSellBetInfo = ( export const getSellBetInfo = (
user: User, user: User,
@ -9,17 +9,17 @@ export const getSellBetInfo = (
contract: Contract, contract: Contract,
newBetId: string newBetId: string
) => { ) => {
const { id: betId, amount, shares, outcome } = bet; const { id: betId, amount, shares, outcome } = bet
const { YES: yesPool, NO: noPool } = contract.pool; const { YES: yesPool, NO: noPool } = contract.pool
const { YES: yesStart, NO: noStart } = contract.startPool; const { YES: yesStart, NO: noStart } = contract.startPool
const { YES: yesShares, NO: noShares } = contract.totalShares; const { YES: yesShares, NO: noShares } = contract.totalShares
const { YES: yesBets, NO: noBets } = contract.totalBets; const { YES: yesBets, NO: noBets } = contract.totalBets
const [y, n, s] = [yesPool, noPool, shares]; const [y, n, s] = [yesPool, noPool, shares]
const shareValue = const shareValue =
outcome === "YES" outcome === 'YES'
? // https://www.wolframalpha.com/input/?i=b+%2B+%28b+n%5E2%29%2F%28y+%28-b+%2B+y%29%29+%3D+c+solve+b ? // https://www.wolframalpha.com/input/?i=b+%2B+%28b+n%5E2%29%2F%28y+%28-b+%2B+y%29%29+%3D+c+solve+b
(n ** 2 + (n ** 2 +
s * y + s * y +
@ -34,50 +34,50 @@ export const getSellBetInfo = (
Math.sqrt( Math.sqrt(
y ** 4 + (s - n) ** 2 * n ** 2 + 2 * y ** 2 * n * (s + n) y ** 4 + (s - n) ** 2 * n ** 2 + 2 * y ** 2 * n * (s + n)
)) / )) /
(2 * n); (2 * n)
const startPool = yesStart + noStart; const startPool = yesStart + noStart
const pool = yesPool + noPool - startPool; const pool = yesPool + noPool - startPool
const probBefore = yesPool ** 2 / (yesPool ** 2 + noPool ** 2); const probBefore = yesPool ** 2 / (yesPool ** 2 + noPool ** 2)
const f = pool / (probBefore * yesShares + (1 - probBefore) * noShares); const f = pool / (probBefore * yesShares + (1 - probBefore) * noShares)
const myPool = outcome === "YES" ? yesPool - yesStart : noPool - noStart; const myPool = outcome === 'YES' ? yesPool - yesStart : noPool - noStart
const adjShareValue = Math.min(Math.min(1, f) * shareValue, myPool); const adjShareValue = Math.min(Math.min(1, f) * shareValue, myPool)
const newPool = const newPool =
outcome === "YES" outcome === 'YES'
? { YES: yesPool - adjShareValue, NO: noPool } ? { YES: yesPool - adjShareValue, NO: noPool }
: { YES: yesPool, NO: noPool - adjShareValue }; : { YES: yesPool, NO: noPool - adjShareValue }
const newTotalShares = const newTotalShares =
outcome === "YES" outcome === 'YES'
? { YES: yesShares - shares, NO: noShares } ? { YES: yesShares - shares, NO: noShares }
: { YES: yesShares, NO: noShares - shares }; : { YES: yesShares, NO: noShares - shares }
const newTotalBets = const newTotalBets =
outcome === "YES" outcome === 'YES'
? { YES: yesBets - amount, NO: noBets } ? { YES: yesBets - amount, NO: noBets }
: { YES: yesBets, NO: noBets - amount }; : { YES: yesBets, NO: noBets - amount }
const probAfter = newPool.YES ** 2 / (newPool.YES ** 2 + newPool.NO ** 2); const probAfter = newPool.YES ** 2 / (newPool.YES ** 2 + newPool.NO ** 2)
const creatorFee = CREATOR_FEE * adjShareValue; const creatorFee = CREATOR_FEE * adjShareValue
const saleAmount = (1 - CREATOR_FEE - PLATFORM_FEE) * adjShareValue; const saleAmount = (1 - CREATOR_FEE - PLATFORM_FEE) * adjShareValue
console.log( console.log(
"SELL M$", 'SELL M$',
amount, amount,
outcome, outcome,
"for M$", 'for M$',
saleAmount, saleAmount,
"M$/share:", 'M$/share:',
f, f,
"creator fee: M$", 'creator fee: M$',
creatorFee creatorFee
); )
const newBet: Bet = { const newBet: Bet = {
id: newBetId, id: newBetId,
@ -93,9 +93,9 @@ export const getSellBetInfo = (
amount: saleAmount, amount: saleAmount,
betId, betId,
}, },
}; }
const newBalance = user.balance + saleAmount; const newBalance = user.balance + saleAmount
return { return {
newBet, newBet,
@ -104,5 +104,5 @@ export const getSellBetInfo = (
newTotalBets, newTotalBets,
newBalance, newBalance,
creatorFee, creatorFee,
}; }
}; }

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@ -1,10 +1,10 @@
export type User = { export type User = {
id: string; id: string
email: string; email: string
name: string; name: string
username: string; username: string
avatarUrl: string; avatarUrl: string
balance: number; balance: number
createdTime: number; createdTime: number
lastUpdatedTime: number; lastUpdatedTime: number
}; }

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@ -1 +1 @@
export const randomString = () => Math.random().toString(16).substr(2, 14); export const randomString = () => Math.random().toString(16).substr(2, 14)

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@ -1,16 +1,16 @@
export const slugify = ( export const slugify = (
text: string, text: string,
separator = "-", separator = '-',
maxLength = 35 maxLength = 35
): string => { ): string => {
return text return text
.toString() .toString()
.normalize("NFD") // split an accented letter in the base letter and the acent .normalize('NFD') // split an accented letter in the base letter and the acent
.replace(/[\u0300-\u036f]/g, "") // remove all previously split accents .replace(/[\u0300-\u036f]/g, '') // remove all previously split accents
.toLowerCase() .toLowerCase()
.trim() .trim()
.replace(/[^a-z0-9 ]/g, "") // remove all chars not letters, numbers and spaces (to be replaced) .replace(/[^a-z0-9 ]/g, '') // remove all chars not letters, numbers and spaces (to be replaced)
.replace(/\s+/g, separator) .replace(/\s+/g, separator)
.substring(0, maxLength) .substring(0, maxLength)
.replace(new RegExp(separator + "+$", "g"), ""); // remove terminal separators .replace(new RegExp(separator + '+$', 'g'), '') // remove terminal separators
}; }