在機器學習於金融領域的應用中，目前較多的實驗是以每一段期間內的成交資訊作為機器學習的輸入特徵，如開盤價、收盤價以及成交量......等等。機器學習可用於預測未來市場的趨勢，並結合交易策略對歷史資料進行交易回測(Backtest)。在回測效能評估大致上可以分為收益與風險這兩個種類，模型訓練的目標即是將收益最大化以及最小化交易期間所承受的風險。
在本文中使用含有逐筆交易訊息的限價委託簿(Limit Order Book)作為深度強化學習模型的訓練資料，我使用了三個種類的特徵來描述當前交易市場的狀態作為模型的訓練特徵，分別為限價委託簿的當前狀態、限價委託簿的動態變化以及模型的帳戶狀態，經由實驗挑選出最適合用於訓練模型的特徵集。在獎勵函數(Reward Function)的設計上，我的設計目標是基於高頻交易(High Frequency Trading)的概念，在每一次的買賣間賺取小額獲利，並藉由較高的勝率以及頻繁的交易來累積獲利。設計方式是藉由在過短時間內進行平倉的行為給予懲罰，同時對於能夠賺取小額獲利的行為給予獎勵。本篇論文所使用的近端策略優化演算法(Proximal Policy Optimization, PPO)是一種演員評論家(Actor-Critic)演算法，藉由建構兩個不同的神經網路來對模型進行訓練。
本篇論文討論了模型在各種不同的情況下獲利相關指標的變化。我使用西元2022年4月26日至西元2022年6月15日的臺股期貨逐筆交易資料對模型進行訓練與回測。在考量交易經手費、結算手續費以及期貨交易稅這三個交易成本的情況下，回測期間表現最好的模型勝率可達59.55%，獲利因子可達1.62。

In the application of machine learning in the financial field, many experiments use the transaction information during a period of time as the input feature of machine learning, such as opening price, closing price, and transaction volume. Machine learning can be used to predict future market trends and combine trading strategies to backtest on historical data. The backtest performance evaluation can be roughly divided into profit and risk. The goal of training model is to maximize the profit and minimize the risk during the transaction.
In this paper, the limit order book containing tick by tick transaction information has been used as the training data for the deep reinforcement learning model. I have used three types of features to describe the current trading market state as the training features of the model. It’s the current state of limit order book, the dynamic changes of limit order book, and the account status of the deep reinforcement learning model. I have selected the most suitable feature sets for training model by doing experiment. I have designed the reward function based on the concept of high frequency trading, accumulating profit by trading frequently and high win rate. Giving negative reward for closing a position too fast and giving positive reward for earning profit. I used proximal policy optimization algorithm in my research, and constructing two different neural network to train the model.
I have discussed the profit-related indicators under different conditions. I used TAIEX tick data during 26/4/2022 to 6/15/2022 to train and test the model. Considering brokerage fee, settlement fee and transfer tax, the best-performing model reach 59.55% win rate, and the profit factor reach 1.62 during the backtest period.

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