避險基金在金融市場中是獨具特色的投資工具，其資訊的不透明性與多樣的投資策略讓它帶有較高的收益，但同時也使得其運作依賴基金經理人的專業知識。當基金經理人的投資決策導致失敗，避險基金可能會被撤銷，造成投資者遭受資金損失。因此，掌握避險基金撤銷事件的可能觸發因素，以及進行適當的風險管理，顯得尤為重要。
過去的研究多採用 Cox 比例風險模型來研究避險基金在市場上的存活時間，模型假設存活時間與設限時間必須為獨立。而在實際的金融市場中，避險基金的存活時間可能受到許多因素的影響，從而使得存活時間與設限時間可能存在相依性。
鑒於此，本研究將採用 Clayton Copula 函數，以彌補 Cox 比例風險模型的一些限制，運用 Copula 模型和 Cox 比例風險模型於模擬實驗和實際的避險基金資料上，比較兩種模型的預測結果。本研究使用 BFGS 迭代方法來提升 Copula 模型執行效率，並且在研究中發現，無論在模擬實驗和避險基金資料 Copula 模型的預測能力都比 Cox 比例風險模型佳。通過此研究，期望能更深入理解不同變數如何影響避險基金的風險模型，並提供給基金經理人作為參考。

Hedge funds constitute a distinctive investment vehicle in the financial market. Their effective operation, owing to information asymmetry and diverse investment strategies, hinges significantly on the professional acumen of fund managers. Hence, it is paramount to identify potential triggers contributing to hedge fund failures and implement effective risk management strategies.
Liquidation risk has played an important part in the hedge fund literature. Traditionally, the Cox proportional hazard model has become a popular approach to estimating causal effects for censored timing observations. One key assumption of the Cox model is the independence of survival time and censoring time. Nevertheless, a multitude of factors potentially influences the survival time of hedge funds. To address this problem, we apply the Copula model to gauge the impact and account for dependent censoring when estimating the propensity of hedge fund liquidation risk. Further, a comparative analysis is performed between the behaviors of the Copula model and the Cox model, utilizing both simulation and the case study. From simulations and case study, it can be seen that the Copulas model demonstrates superior performance over the Cox proportional hazards model.

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