Correlation when it counts

Two coins' daily returns have a correlation of 0 over a month. What does that tell you?

• They will never fall on the same day
• Over that month, being above or below average on one coin said nothing consistent about the other
• They each moved by about the same amount

A dollar token holds $1 on most exchanges but prints $0.70 on the exchange where it backs your loan. Which price is used for your position?

• $1, because that is the fair price
• The average of all exchanges
• $0.70, because your position is valued on its own venue