Media trading groups and short selling manipulation
研究了通过社交媒体形成的交易群体如何影响股价，以及这一动态博弈对市场效率和社会福利的经济后果。
This paper models how chatroom traders, forming a coalition via social media platforms, influence the stock price in the presence of large and strategic short sellers. The economic consequences of this dynamic game are studied in an equilibrium framework with strategic trading. Various equilibrium phenomena arise, including price bubbles, short squeezes, forced liquidations, and precautionary savings by the large trader. Media groups discipline the large trader's incentive to short sell, but it can either increase or decrease market allocational efficiency. Additionally, it uniformly improves social welfare under the belief-neutral welfare criterion.