The TRADE 63 - Q1 2020 | Page 96

[ D ATA ] DO YOU KNOW HOW YOUR ORDERS ARE ROUTED? Do you know how your order is routed? Should you care? Lately, more and more emphasis is being placed on how orders are routed. Typically concerns are raised around whether brokers are routing in their own best interest or in their clients’ best interest. Other considerations relate to whether certain trading venues are ‘toxic’ and lead to deterioration of performance. L et’s begin with a bit of back- ground. In order to realise an investment opportunity, traders must first acquire a position. They can do this by buying or selling shares of stock in the ‘market’. While this sounds quite simple and maybe obvious, the term ‘market’ hides a lot of complexity. The reason is that the ‘market’ consists of many places to trade. While many years ago, there was typically only a single place to trade (often called an exchange), we now have many places to trade, some with names like MTFs, ATSs or ECNs. This means that we need to make choices about which of these venues to interact with when we go to purchase shares of stock. We also need to consider the ways in which we interact with the collection of trading venues we refer to as 96 // TheTRADE // Spring 2020 the ‘market’. While there are many possible ques- tions to address, three key questions we would like to answer regarding our order are: When did we execute? Where did we execute? and how did we execute? The portfolio manager generally knows why they want to execute, but the other three questions all relate to how the order was managed by a broker. The brokers use technologies such as algos that determine timing, and routers that determine where to direct the order and the way to execute. One of the key things being managed in this approach is market impact. When we go to the market, we don’t want to move the market too much as that can only hurt our performance. At the same time, the role of the market is to provide price discovery – the process of finding equilibrium prices that balance supply and demand. Therefore, we want to develop tools that can allow us to de- termine the answers to the questions of where, when and how we should trade so we can understand why we got the outcome we did. Ultimately, what we want to be able to do is to see the big picture of how our order interacted with the market. It therefore seems natural to visualise this interaction in a picture. We can develop such a picture by plotting the way we interacted along three dimensions. The first dimension we care about is time – we want to answer the question ‘when did we trade?’ We want to be able to show how much volume we traded as a function of