Abstract
In the past few decades, scholars have
made extensive research on the breadth of ownership or the comovement of equity
prices separately. However, the connection between these two factors has not
been revealed. This paper attempts to find out the relationship between them
and address this gap. Based on “A Simple Model of Capital Market Equilibrium
with Incomplete Information” built up by Merton in 1987, I find that breadth of
ownership have a great impact on the stock prices comovement with the market.
As the breadth of ownership increases, the comovement between the stock prices
and the market also increases. Besides, I find that some characters of stocks
also affect this relationship, such as growth ability, volatility and the
shareholders’ risk preferences. Higher growth ability, volatility or
risk-aversion among shareholders could amplify this effect. Using data in China
stock market between 2003 and 2014, I find that a 10%-increase in the number of
shareholders of a stock is associated with additional 0.0113-0.0170 (about
1.08%-1.62%) increase in its beta with the market when other things are hold
equal. It provides great evidence that investor behavior can affect the stock
price comovement with the market.
JEL classification numbers: G40, G11, G12
Keywords: Breadth of
Ownership, Comovement, Investor Behavior