本文旨在從金融治安的觀點，檢驗在什麼時間比較可能發生銀行搶劫案件，而金融機構搶案結果和時間的關連性為何？作者藉由「理性選擇理論」（rational choice theory）的觀點，闡述銀行搶匪的行為動機，以及說明時間因素為什麼是搶犯決定採取行動的重要考量。為檢證相關命題，本文蒐集1982年至2020年《聯合知識庫》和《司法院法學資料檢索系統》資料，臺灣共計發生378件金融機構搶劫案件，這些案件的犯案人數有504位，本文以這些搶犯做為分析對象。根據依變數特性，本文以「層狀勝算對數模型」（hierarchical logit model）進行兩個分析層級，檢證搶劫案件的成功與否受到什麼因素的影響，尤其在時間因素方面有無顯著差異。除了量化分析之外，本文亦進行「半結構式深度訪談」（semi-structured intensive interviews）。資料顯示，金融機構類型、星期、時段、犯案人數、犯案工具等變數，對於銀行搶案結果具有顯著效應。整體而言，在時間因素方面，週五、上午11時至中午13時59分，以及15時之後的時段，安全警戒心態可能較為鬆散，致使搶匪心生歹念，這是金融單位安全防備需要強化的時刻。

This study investigates the questions of when bank robberies are most likely to occur, and what is the proximate relationship between the outcomes and the timing of financial institution heists from the perspective of crime prevention. Using rational choice theory, we examine the behavioral motives of bank robbers and explain why the time factor is a major consideration in the robber’s decision to act. To test the hypotheses, this study collected bank heist data from the United Daily News Database (UDNDATA) and the Law and Regulations Retrieving System of the Judicial Yuan. A total of 378 bank robberies occurred in Taiwan between 1982 and 2020, involving 504 criminals. Given the characteristic of the dependent variable, the study conducts a two-level analysis using hierarchical logit models. We evaluate the factors that affect the success (or failure) of bank robberies, paying close attention to whether significant differences exist with respect to time factors. In addition to quantitative analyses, we conduct semi-structured intensive interviews. Empirical results reveal that variables such as the type of financial institution, the day of the week, the time of day, the number of criminals, and the tools used in the heist all have a statistically significant effect on the outcome of bank robberies. In general, levels of security alert are likely lower on Fridays, in the hours between 11 a.m. and 2 p.m., and in the period after 3 p.m., which leads robbers to strike at those times. Accordingly, these are the time periods during which financial institutions need to beef up their security precautions.