The quality of price formation at market openings and closings: evidence from the Nasdaq stock market

Central counterparties (CCPs) have increasingly become a cornerstone of financial markets infrastructure. We present a model where trades are time-critical, liquidity is limited and there is limited enforcement of trades. We show a CCP novating trades implements efficient trading behaviour. It is optimal for the CCP to face default losses to achieve the efficient level of trade. To cover these losses, the CCP optimally uses margin calls, and, as the default problem becomes more severe, also requires default funds and then imposes position limits

Market sidedness: Insights into motives for trade initiation

In this paper, we infer motives for trade initiation from market sidedness. We define trading as more two-sided (one-sided) if the correlation between the numbers of buyerand seller-initiated trades increases (decreases), and assess changes in sidedness (relative to a control sample) around events that identify trade initiators. Consistent with asymmetric information, trading is more one-sided prior to merger news. Consistent with belief heterogeneity, trading is more two-sided (1) before earnings and macro announcements with greater dispersions of analyst forecasts and (2) after earnings and macro news events with larger announcement surprises. A simultaneous equation system is used to examine the co-determinacy of sidedness, the bid-ask spread, volatility, the number of trades, and the order imbalance

Two-sided markets and intertemporal trade clustering: Insights into trading motives

We show that equity markets are typically two-sided and that trades cluster in certain trading intervals for both NYSE and Nasdaq stocks under a broad range of conditions-news and non-news days, different times of the day, and a spectrum of trade sizes. By “two-sided” we mean that the arrivals of buyer-initiated and seller-initiated trades are positively correlated; by “trade clustering” we mean that trades tend to bunch together in time with greater frequency than would be expected if their arrival were a random process. Controlling for order imbalance, number of trades, news, and other microstructure effects, we find that two-sided clustering is associated with higher volatility but lower trading costs. Our analysis has implications for trading motives, market structure, and the process by which new information is incorporated into market prices