We propose a model to describe stock pinning on option expiration dates. We argue that if the open interest in a particular contract is unusually large, Delta-hedging in aggregate by floor market-makers can impact the stock price and drive it to the strike price of the option. We derive a...

We study the price-evolution of stocks that are subject to restrictions on short-selling, generically referred to as hard-to-borrow. Such stocks are either subject to regulatory short-selling restrictions or have insufficient float available for lending. Traders with short positions risk being...

We model and study the behavior of bankrupt stocks. We are interested in the dynamics of stocks and options, and in particular the cost of establishing positions with negative delta.This extends a model of Avellaneda and Lipkin which was used to model hard-to-borrow stocks. This model is a...

We propose a model to describe stock pinning on option expiration dates. We argue that if the open interest on a particular contract is unusually large, delta-hedging in aggregate by floor market-makers can impact the stock price and drive it to the strike price of the option. We derive a...

We study model-driven statistical arbitrage in US equities. Trading signals are generated in two ways: using Principal Component Analysis (PCA) or regressing stock returns on sector Exchange Traded Funds (ETFs). In both cases, the idiosyncratic returns are modelled as mean-reverting processes,...

We present an algorithm for hedging option portfolios and custom-tailored derivative securities, which uses options to manage volatility risk. The algorithm uses a volatility band to model heteroskedasticity and a non- linear partial differential equation to evaluate worst-case volatility...