本國股市波動易受投資者之情緒變化，而投資者則會因為新聞而導致投資決策的改變。本文透過爬蟲技術取得近十年華爾街日報科技版的每日新聞資料，結合深度學習模型進行情感分析，期望能夠幫助投資者更好地了解股票市場的變化。現有的情感分析大多缺少金融詞彙的訓練，故本文利用 FinBERT 預訓練模型去學習金融新聞語義的特徵，解決上述問題並針對臺灣及美國的科技類股指數的市場報酬率進行分析。研究發現，在科技領域的股市中，華爾街日報只會影響臺灣股價，並不會影響美國股價，故華爾街日報在臺灣股市之中可視為領先指標，反之，在美國股市中為落後指標，另外，在臺灣科技股股市中， COVID19 事件發生後會增加股市的波動性，對市場的可解釋力也上升。除此之外，由華爾街日報得出的情緒分數變動量和台灣及美國科技股市中之報酬率存在邊際效果遞減，故本研究認為情緒因子可以加入其他迴歸模型以得到更好的預測能力。

The domestic stock market is highly sensitive to changes in investor sentiment, and investors often make investment decisions based on news. This paper uses web crawling technology to obtain daily news data from the technology section of The Wall Street Journal over the past decade. The author then use a deep learning model for sentiment analysis to better understand changes in the stock market. Existing sentiment analysis methods mostly lack training on financial vocabulary, so this study uses the FinBERT pre-training model to learn the semantic features of financial news, addressing this issue and analyzing the market returns of Taiwan and US technology sector indices. The study found that The Wall Street Journal only affects Taiwan's stock prices in the technology sector, and doesn't affect US stock prices. Therefore, The Wall Street Journal can be considered a leading indicator in the Taiwan stock market, whereas it is a lagging indicator in the US stock market. After the COVID-19 event, not only did it increase the volatility of the stock market, but also the market's interpretability. In addition, the marginal effect of the sentiment score volatility derived from The Wall Street Journal on the returns of both Taiwan and US markets exhibits diminishing marginal returns, so this study believes that sentiment factors can be added to other regression models to achieve better predictive ability.

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