不確定性對於國家經濟體系是一顆未爆彈，過去文獻皆表明當發生金融危機時不確定性將同步上升，反應了國民的恐慌程度，因此不確定性可以說是與金融危機高度相關的，且不確定性難以衡量，故建置不確定性代理指標有其必要性，也是近年來的重點研究領域。而台灣很少有針對不確定性指標的建置的相關研究，因此本研究嘗試為台灣建構不確定指數。
　　本文介紹了一個在網路上進行大規模資料收集的方法，通過線上搜尋引擎Google Trends中所獲得的資料，整理並建構了一個屬於台灣的經濟不確定性指標－GTU指數(Google Trends Uncertainty Index)，將台灣的經濟不確定性量化，觀察到GTU指數在金融海嘯、歐債危機、美中貿易戰期間顯著上升。
　　除了指標的建構外，本研究試圖理解經濟不確定性對台灣實質經濟的直接影響。實證結果顯示，本文所建構的GTU指數對台灣的投資市場、產出、消費、就業市場均有顯著的負面影響效果，與過去的文獻一致，則說明本文所建構的經濟不確定性指標確實能夠有效解釋台灣的總體經濟環境。
　　使用Google Trends的資料有公開、免費、快速等優勢，且能夠及時並直接地反應人民對於總體經濟環境變化的關注程度，因此本文所建構的經濟不確定性指標為國民的情緒指標提供一個不同的參考價值。

　　Uncertainty is an unexploded bomb for the economic system. Past literature shows that when a financial crisis occurs, uncertainty will rise synchronously. It reflects the level of public anxiety. Therefore, uncertainty is highly correlated with financial crises. Since uncertainty is difficult to measure, it is necessary to build a proxy indicator about uncertainty, it’s also a main research field in recent years. However, there are few related studies about how to build the uncertainty indicators of Taiwan. In this study, I attempt to construct an uncertainty index for Taiwan.
　　This study introduces a method of large-scale data collection on the Internet. Use the data that obtained from the online search engine－"Google Trends" to build an economic uncertainty index for Taiwan, the "GTU index" (Google Trends Uncertainty Index), aiming to quantify Taiwan's economic uncertainty. The study observes that the GTU index rose significantly during the period of financial crisis, the European debt crisis, and the US-China trade war respectively.
　　In addition to the construction of GTU index, this study attempts to find the direct impact of economic uncertainty on Taiwan's real economic activities. The empirical results show that the GTU index constructed in this study has a significant negative impact on Taiwan's investment market, output, consumption, and employment market, which is consistent with the literature. Thus, indicating that the economic uncertainty index constructed in this study can indeed affect the macro-economic environment of Taiwan.
　　The data searched from Google Trends has the advantages of being open, free, and fast. It can directly reflect people's thoughts on changes in the macro-economic environment without delay. Hence, the economic uncertainty index constructed in this study provides a different reference for national sentiment indicators.

論文審定書 i
誌謝 ii
摘要 iii
Abstract iv
目錄 v
表次 vii
圖次 viii
第一章 緒論 1
第一節 研究背景與動機 1
第二節 研究目的 3
第三節 研究架構 4
第二章 文獻回顧 5
第一節 使用新聞關鍵詞量化經濟不確定性的相關文獻 5
第二節 使用Google Trends研究經濟不確定性的相關文獻 6
第三節 其他相關文獻 8
第三章 研究方法 10
第一節 Google Trends介紹與GTU指數建構 10
（一） Google Trends介紹 10
（二） GTU指數建構 13
第二節 變數定義與資料來源 17
第三節 模型設定 19
（一） 單根檢定 19
（二） 向量自我迴歸模型(VAR Model) 21
（三） Granger因果關係檢定(Granger Causality) 23
（四） 衝擊反應函數(Impulse Response Function) 24
（五） 預測誤差變異數分解(Variance Decomposition) 26
第四章 實證結果與分析 27
第一節 GTU指數 27
第二節 敘述統計與單根檢定 28
第三節 VAR模型 33
第四節 Granger因果關係分析 36
第五節 衝擊反應函數分析 38
第六節 預測誤差變異數分解 42
第五章 結論 56
參考文獻 58
中文文獻 58
英文文獻 58
附錄：穩定性測試(Robustness Test) 62

中文文獻
王沁婕（2021）。恐懼的總和：投資者情緒與台灣股市的影響。國立清華大學財務金融碩士在職專班碩士論文，新竹市。
莊雅筑（2021）。中美貿易戰爭對台灣股票報酬率的影響─以google搜索量分析。國立成功大學經濟學系碩士論文，台南市。
黃裕烈、葉錦徽、陳重吉（2021）。台灣經濟政策不確定性指標之建構與分析。經濟論文叢刊，49(2)，307-334。
黃裕烈、管中閔（2019）。美國聯準會會議紀要的文字探勘與台灣經濟變數預測。經濟論文叢刊，47(3)，363-391。
黃鈺（2017）。臺灣運輸類股報酬、波動及成交量與Google搜尋量指數之關係。國立臺灣海洋大學航運管理學系碩士論文，基隆市。

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