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SEBI Registration (Research Analyst) : INH000000743
August 8, 2016
Interview With A High-Frequency Trader
High-frequency trading (HFT) – wherein computers transact thousands of times per second with incomprehensible speed – now accounts for over 60% of all trades on American exchanges. How does this sweeping market change affect retail investors?
There are two very different answers to that question. Supporters claim that high-frequency traders (HFTs) are a net-positive market force because they provide liquidity and tighten bid-ask spreads. They say that high-frequency trading is rarely if ever used for nefarious purposes, and regulators make sure of it.
On the other side, detractors claim that HFTs regularly manipulate unaware investors and otherwise destabilize markets. They say that HFTs are a net-negative force on the market and should be reined in.
The answer surely lies somewhere in between. But which is closer to the truth? To find out, we talked to Garrett, an expert on market systems and high-frequency trading. Having experienced first-hand the problems HFTs can cause, he fits firmly in the “detractor” camp, for reasons you’ll read below. Garrett gave us excellent insight into how HFTs profit, along with tips on how to make sure they don’t profit at your expense.
I found this interview highly educational, and I hope you do too. It contains the kind of inside intelligence that separates the informed from the uninformed and allows us as individual investors to understand and adapt to our changing markets.
The Casey Report: Hello Garrett, and thanks for taking the time to chat with us. First, can you tell us your back-story and explain how you got into high-frequency trading and real-time trading research?
GARRETT: Sure. I worked for an asset management firm as a portfolio manager’s assistant. We used traditional fundamental analysis to calculate company prices. Beginning with the July 2011 crash, our strategy no longer seemed to be working. We lost a lot of our clients’ money – nearly 40%. It was brutal.
During that same time, I started to notice odd price movements on my charts, ones that I had never seen before. Prices would randomly spike in amounts and directions that made no sense. When I dug deeper, I realized the movements were too fast and too uniform to be human. Computers caused them.
My bosses didn’t understand this, and didn’t want to. I couldn’t raise my concerns because of the old-school culture of the firm. But that refusal to acknowledge the new reality – that computers were increasingly driving the market – was leaving my firm at an enormous competitive disadvantage. Essentially, the market was changing, and we weren’t adapting.
I began to study high-frequency trading on my own. I started by following a few professionals who were sounding the alarm, trying to alert investors that the game has changed. My favorite sources were (and are) Themis Trading and Nanex.
Eventually, I narrowed my focus to study the market micro-structure – which is basically what happens to orders after you click the “buy” or “sell” button on your brokerage platform. That’s where all the action is, and it’s where you can see exactly what the HFTs are doing.
I came to the conclusion that, because of HFTs, our markets are broken and fragmented. I left my old firm in mid-December, took my own money and started running my own shop, based on this premise. My strategy uses software to exploit the dislocations caused by HFT.
TCR: What made you think that high-frequency trading was behind those strange price movements you were seeing?