This paper provides evidence that stock traders focus on round numbers as cognitive reference points for value. Using a random sample of more than 100 million stock transactions, we find excess buying (selling) by liquidity demanders at all price points one penny below (above) round numbers....

The left-digit effect is defined as when a change in the left-most digit of a price (e.g., 7 to 6 when $7.00 drops to $6.99) dramatically affects the perception of the magnitude. Using a random sample of more than 100 million stock transactions, we find excess buying by liquidity demanders when...

This paper provides evidence that stock traders focus on round numbers as cognitive reference points for value. Using a random sample of more than 100 million stock transactions, we find excess buying (selling) by liquidity demanders at all price points one penny below (above) round numbers....