Learning about machine learning and deep learning algorithm trading, characteristics, and how to generate data over time

1. Introduction

In recent years, algorithmic trading has rapidly developed in the financial markets. Machine learning and deep learning technologies have significantly contributed to improving data analysis and prediction accuracy, thereby becoming essential elements in the composition and operation of automated trading systems. In this course, we will understand the basic concepts and characteristics of algorithmic trading based on machine learning and deep learning, and learn about data generation and processing over time.

2. Understanding the Basics of Machine Learning and Deep Learning

Machine learning is an algorithm that learns patterns and makes predictions from data. The main goal of machine learning is to derive outcomes from given input data. Deep learning is a field of machine learning that uses artificial neural networks to learn more complex patterns. In the stock market, three types of machine learning models are commonly used:

  • Supervised Learning: The model learns based on given input data and output data.
  • Unsupervised Learning: Only input data is provided, and the model learns the patterns or structures of the data on its own.
  • Reinforcement Learning: An agent selects actions and learns the optimal policy by receiving rewards as a result of those actions.

3. Data Generation and Preprocessing

3.1. Data Collection

For algorithmic trading, financial data is needed first. Data such as stock prices, trading volumes, and technical analysis indicators are primarily used. This data can be collected from various APIs or financial data providers. For example, you can collect stock data using the yfinance library in Python.

import yfinance as yf

# Get Apple's stock data.
data = yf.download("AAPL", start="2020-01-01", end="2023-01-01")
print(data.head())
            

3.2. Data Preprocessing

Collected data often includes noise or incompleteness. Therefore, it needs to be preprocessed into a suitable form for analysis. The preprocessing stage generally includes handling missing values, normalization, scaling, and so on. For example, to scale the data, you can use Min-Max scaler to convert stock prices to a range between 0 and 1.

from sklearn.preprocessing import MinMaxScaler

# Initialize and fit MinMaxScaler
scaler = MinMaxScaler()
scaled_data = scaler.fit_transform(data[['Close']])
            

4. Feature Generation and Selection

The performance of machine learning models greatly depends on the features. Therefore, the process of generating and selecting appropriate features is very important. Commonly used feature generation methods include technical indicators and statistical indicators such as moving averages and the Relative Strength Index (RSI).

4.1. Moving Average

The moving average is used to determine the trend of stock prices by calculating the average price over a specific period. For example, the code to calculate the 20-day moving average is as follows.

data['SMA_20'] = data['Close'].rolling(window=20).mean()
            

4.2. Relative Strength Index (RSI)

The RSI is an indicator used to determine whether the stock price is overbought or oversold. To calculate the RSI, the averages of gains and losses must be utilized.

def compute_rsi(data, window=14):
    delta = data['Close'].diff()
    gain = (delta.where(delta > 0, 0)).rolling(window=window).mean()
    loss = (-delta.where(delta < 0, 0)).rolling(window=window).mean()
    rs = gain / loss
    rsi = 100 - (100 / (1 + rs))
    return rsi

data['RSI'] = compute_rsi(data)
            

5. Model Training and Evaluation

5.1. Model Selection

Machine learning models include regression models, decision trees, random forests, and SVMs, while deep learning models include LSTM (Long Short-Term Memory) and CNN (Convolutional Neural Network). Each model has its unique characteristics and advantages, and it is important to choose the model suitable for the given problem.

5.2. Model Training

The chosen model is trained using the training data. Model training is generally carried out in the direction of minimizing the loss function. For example, the code to configure an LSTM model using TensorFlow is shown below.

import tensorflow as tf
from tensorflow.keras.models import Sequential
from tensorflow.keras.layers import LSTM, Dense

model = Sequential()
model.add(LSTM(50, activation='relu', input_shape=(X_train.shape[1], X_train.shape[2])))
model.add(Dense(1))
model.compile(optimizer='adam', loss='mean_squared_error')
model.fit(X_train, y_train, epochs=50, batch_size=32)
            

5.3. Model Evaluation

During the model evaluation stage, the test data is used to measure the model's performance. Various metrics, such as MSE (Mean Squared Error), can be used for evaluation. Additionally, the predictions of the trained model can be visualized for intuitive evaluation.

import matplotlib.pyplot as plt

predictions = model.predict(X_test)
plt.plot(y_test, label='Actual Values')
plt.plot(predictions, label='Predicted Values')
plt.legend()
plt.show()
            

6. Building an Actual Algorithmic Trading System

Based on what we have learned so far, we can build a real algorithmic trading system. This system will include the ability to make decisions based on given data and automatically execute orders.

6.1. Generating Trade Signals

Trade signals are indicators that determine the timing of buying or selling stocks. For example, you can generate trade signals using a moving average crossover. The code below is an example of implementing a simple trading strategy.

data['Signal'] = 0
data['Signal'][20:] = np.where(data['SMA_20'][20:] > data['Close'][20:], 1, 0)
            

6.2. Order Execution and Portfolio Management

Once trade signals are generated, actual orders are executed based on them. Most trading platforms support executing orders automatically via APIs, and there should also be features for managing the performance of the portfolio.

import requests

def send_order(signal):
    if signal == 1:
        # Code to execute a buy order
        requests.post("API_ENDPOINT", data={"action": "buy", "quantity": 1})
    elif signal == -1:
        # Code to execute a sell order
        requests.post("API_ENDPOINT", data={"action": "sell", "quantity": 1})
            

7. Conclusion

Machine learning and deep learning algorithmic trading are powerful tools for gaining profits in the financial markets. This course covered the process from data collection, preprocessing, feature generation, model training and evaluation, to building a real algorithmic trading system. Above all, it is important to remember that the success of algorithmic trading relies on continuous data analysis and model improvement.

8. References

  • Goodfellow, I., Bengio, Y., & Courville, A. (2016). Deep Learning. MIT Press.
  • Harvey, C. R., Liu, Y., & Zhu, H. (2016). ...
  • Kirkpatrick, S., & Hoyer, C. (2020). ...