Algorithmic trading is usually perceived as a complex area for beginners to get to grips with. It covers a wide range of disciplines, with certain aspects requiring a significant degree of mathematical and statistical maturity. Consequently it can be extremely off-putting for the uninitiated. In reality, the overall concepts are straightforward to grasp, while the details can be learned in an iterative, ongoing manner.
The beauty of algorithmic trading is that there is no need to test out ones knowledge on real capital, as many brokerages provide highly realistic market simulators. While there are certain caveats associated with such systems, they provide an environment to foster a deep level of understanding, with absolutely no capital risk.
A common question that I receive from readers of QuantStart is "How do I get started in quantitative trading?". I have already written a beginner's guide to quantitative trading, but one article cannot hope to cover the diversity of the subject. Thus I've decided to recommend my favourite entry-level quant trading books in this article.
The first task is to gain a solid overview of the subject. I have found it be far easier to avoid heavy mathematical discussions until the basics are covered and understood. The best books I have found for this purpose are as follows:
1) Quantitative Trading by Ernest Chan - This is one of my favourite finance books. Dr. Chan provides a great overview of the process of setting up a "retail" quantitative trading system, using MatLab or Excel. He makes the subject highly approachable and gives the impression that "anyone can do it". Although there are plenty of details that are skipped over (mainly for brevity), the book is a great introduction to how algorithmic trading works. He discusses alpha generation ("the trading model"), risk management, automated execution systems and certain strategies (particularly momentum and mean reversion). This book is the place to start.
2) Inside the Black Box by Rishi K. Narang - In this book Dr. Narang explains in detail how a professional quantitative hedge fund operates. It is pitched at a savvy investor who is considering whether to invest in such a "black box". Despite the seeming irrelevance to a retail trader, the book actually contains a wealth of information on how a "proper" quant trading system should be carried out. For instance, the importance of transaction costs and risk management are outlined, with ideas on where to look for further information. Many retail algo traders could do well to pick this up and see how the 'professionals' carry out their trading.
3) Algorithmic Trading & DMA by Barry Johnson - The phrase 'algorithmic trading', in the financial industry, usually refers to the execution algorithms used by banks and brokers to execute efficient trades. I am using the term to cover not only those aspects of trading, but also quantitative or systematic trading. This book is mainly about the former, being written by Barry Johnson, who is a quantitative software developer at an investment bank. Does this mean it is of no use to the retail quant? Not at all. Possessing a deeper understanding of how exchanges work and "market microstructure" can aid immensely the profitability of retail strategies. Despite it being a heavy tome, it is worth picking up.
Once the basic concepts are grasped, it is necessary to begin developing a trading strategy. This is usually known as the alpha model component of a trading system. Strategies are straightforward to find these days, however the true value comes in determining your own trading parameters via extensive research and backtesting. The following books discuss certain types of trading and execution systems and how to go about implementing them:
4) Algorithmic Trading by Ernest Chan - This is the second book by Dr. Chan. In the first book he eluded to momentum, mean reversion and certain high frequency strategies. This book discusses such strategies in depth and provides significant implementation details, albeit with more mathematical complexity than in the first (e.g. Kalman Filters, Stationarity/Cointegration, CADF etc). The strategies, once again, make extensive use of MatLab but the code can be easily modified to C++, Python/pandas or R for those with programming experience. It also provides updates on the latest market behaviour, as the first book was written a few years back.
5) Trading and Exchanges by Larry Harris - This book concentrates on market microstructure, which I personally feel is an essential area to learn about, even at the beginning stages of quant trading. Market microstructure is the "science" of how market participants interact and the dynamics that occur in the order book. It is closely related to how exchanges function and what actually happens when a trade is placed. This book is less about trading strategies as such, but more about things to be aware of when designing execution systems. Many professionals in the quant finance space regard this as an excellent book and I also highly recommend it.
At this stage, as a retail trader, you will be in a good place to begin researching the other components of a trading system such as the execution mechanism (and its deep relationship with transaction costs), as well as risk and portfolio management. I will dicuss books for these topics in later articles.