I study a model of market-liquidity provision by levered intermediaries that, besides operating trading desks, run deposit-taking franchises. Levered intermediaries’ heightened incentive to absorb risk helps to counteract liquidity-provision frictions that, in an unlevered economy, would lead...

We introduce a dynamic network model with probabilistic link functions that depend on stochastically time-varying parameters. We adopt the widely used blockmodel framework and allow the high-dimensional vector of link probabilities to be a function of a low-dimensional set of dynamic factors....

We introduce a new model for time-varying spatial dependence. The model extends the well-known static spatial lag model. All parameters can be estimated conveniently by maximum likelihood. We establish the theoretical properties of the model and show that the maximum likelihood estimator for the...

This paper links the recent fragmentation in equity trading to high frequency traders (HFTs). It shows how the success of a new market, Chi-X, critically depended on the participation of a large HFT who acts as a modern market-maker. The HFT, in turn, benefits from low fees in the entrant...