The study looked at why some companies' stock prices go up a lot on their first day of trading when they go public. They studied companies in Taiwan from 2009-2011 and found that factors like how much extra stock is sold, how much the market is going up, how much the stock is traded on the first day, and how much the managers still own of the company can affect how much the stock goes up. They found that these factors are especially important for high-tech companies.