目的：探討中華職業棒球大聯盟(簡稱中華職棒)野手球員於一軍例行賽中，球員的國籍、在中華職棒的年資、所屬球隊、與換隊次數等因素及交互作用對其績效表現的影響。方法：使用二階段分析1990年至2010年所有中華職棒野手球員的資料。第一階段首先使用產出導向型資料包絡分析衡量球員的效率值作為績效指標。第二階段再以截斷式迴歸與拔靴法進行2000次重複抽樣，以降低傳統二階段分析法產生的偏誤。結果：在控制不同球隊的效果後，在主效果方面，國籍和年資對球員的績效有正向影響，換隊次數則為負向效果，國籍與年資則具有交互作用。結論：中華職棒外籍野手球員在一軍例行賽中，績效顯著優於本國籍野手球員。隨年資的累積，野手球員在中華職棒的績效也漸入佳境。但野手球員的績效會隨其換隊次數的增加而下降。當野手球員在中華職棒的年資增加時，外籍球員的績效會隨之上昇，但本國籍球員卻逐漸下降。

Purpose: The present study aimed to explore the impact of nationality, team, tenure, frequency of switching teams, and the interaction effects on batters’ efficiency on regular season for Chinese Professional Baseball League (CPBL) during 1990-2010. Methods: A two-staged data envelopment analysis (DEA) with the output-oriented assumption was used to assess batters’ efficiency in the first stage. To diminish the biases generated from a two-staged estimation, a truncated regression with 2000 bootstrapped procedure (Simar & Wilson, 2007) was employed to evaluate the contributions of independent variables and the interaction effects on batters’ efficiency. Results: The results indicated that after the effect of teams was controlled, there were positive main effects of nationality and tenure in CPBL on batters’ efficiency, but a negative effect of the frequency of team switching in CPBL on batters’ efficiency. The interaction of nationality and tenure in CPBL was significantly impacted batters’ efficiency. Conclusion: The efficiency of foreign batters was higher than that of domestic batters. In addition, the tenure in CPBL would benefit batter’s efficiency. On the contrary, frequency of team switching in CPBL would be harmful to batter’s efficiency. Notably, the relationship between the tenure in CPBL and efficiency to regular season would be positive among foreign batters, whereas it would be negative among domestic batters.