本文以全球智慧型手機市場為例探討了企業所採用品質策略的競爭效應並分析其對各種品質策略偏好的關鍵因素。突破以往依賴主觀判斷的傳統方法，我們使用 K-prototypes 演算法以可量化的規格資料透過分群分析客觀地衡量品質，以確定企業的品質定位。我們構建了一個不完全訊息離散選擇模型，並應用 Nested Pseudo-Likelihood（NPL）演算法，通過迭代更新選擇機率直至參數收斂來估計企業的品質策略。研究結果顯示，企業更傾向於採用與競爭對手區別的品質策略。此外，我們還發現研發強度在影響企業進入不同品質市場中扮演著關鍵角色，並計算出企業進入各種品質市場所需的研發投入臨界值，為學術研究和產業中的實際應用提供了重要的見解。

This thesis examines the competitive effects of firms' quality strategies and the key factors influencing their preferences for various quality strategies within the global smartphone industry. Moving beyond traditional methods reliant on subjective judgments, we employ data-driven clustering, specifically using the K-prototypes algorithm, to objectively measure quality using quantifiable specification data and ascertain firms' quality positioning. We construct an incomplete information discrete choice model and apply the Nested Pseudo-Likelihood (NPL) algorithm, which iteratively updates choice probabilities until parameter convergence, to estimate firms' quality strategies. The results indicate that firms tend to adopt quality strategies that differentiate them from their rivals. Furthermore, we find that R&D intensity plays a critical role in determining firms' entry into different quality markets, and we calculate the critical R&D investment thresholds necessary for firms to enter various quality market segments. These findings provide valuable insights for both academic research and practical applications in the industry.

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