ETF Arbitrage Game
Calculate NAV from weighted stock baskets, spot mispricings between ETF bid/ask prices, and race three AI traders to the edge.
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Statistics
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Last 30 days| 1 | Boom | +$1,650 |
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How to play
Objective
Spot mispricings between an ETF and its underlying stock basket. Buy underpriced ETFs, sell overpriced ones, and compete against 3 AI traders to maximize your P&L.
What is NAV?
The Net Asset Value (NAV) is the fair value of the ETF, calculated as the weighted sum of the underlying stock prices. Each round you see a table like this:
| Ticker | Weight | Price | W × P |
|---|---|---|---|
| AAPL | 0.25 | $200.00 | $50.00 |
| MSFT | 0.25 | $400.00 | $100.00 |
| GOOGL | 0.25 | $150.00 | $37.50 |
| AMZN | 0.25 | $200.00 | $50.00 |
| $237.50 | |||
NAV = sum of W × P = $237.50
Now compare the NAV to the ETF prices shown below the table:
In this example the NAV ($237.50) is higher than the ask ($233.40), so the ETF is underpriced, so you should Buy. If the NAV were lower than the bid, the ETF would be overpriced and you’d Sell.
Each round
- A random stock basket is chosen at the start and stays the same for the whole game
- Each round the stock prices shift slightly, the Change and % columns show which moved
- Calculate the NAV mentally by summing all weight × price values
- Compare your NAV to the ETF bid and ask prices
- Decide: Buy (NAV > ask), Sell (NAV < bid), or Skip if the difference is too small
- Choose how many units (1-20) to trade, more units means more risk and reward
- Race against 3 AI traders who are also calculating and trading
Scoring example
Continuing the example above, you buy 10 units at the ask price of $233.40:
- Gross P&L
- ($237.50 - $233.40) × 10 = +$41.00
- Transaction cost
- -$10.00
- First trader bonus
- +$6.20 (20%)
- Net P&L
- +$37.20
If you had traded in the wrong direction (sold instead of bought), the gross P&L would be -$41.00, plus you’d still pay the $10 transaction cost.
Tips
- Sum the W × P column to quickly find the NAV, the table does the multiplication for you
- Speed matters, be the first to trade to earn a 20% bonus on your profit
- Skip small opportunities, if the difference between NAV and ETF price is small, the $10 transaction cost may eat your profit
- Size wisely, more units amplifies both gains and losses