鑽石舞台

picture from Internet

1. 群組層次的信息衰減與庫存檢查：一種經驗分析方法

儘管已有許多優化技術來解決庫存記錄不準確（inventory record inaccuracy, IRI）的問題，但對IRI的實證評估仍然缺乏，現有的項目級檢查策略也不能滿足將檢查工作分配給項目組的管理需求。本文在與一家零售商合作來收集檔案數據的基礎上，開發了針對IRI的統計估計和實用優化技術來解決上述問題。本文提出一個連續時間模型（continuous-time model）來解釋群組層次的信息衰減，並基於該模型開發了一個將（庫存記錄）檢查工作分配給一組項目以滿足管理需求的檢查策略。本文對模型行為進行分析，並利用現有信息量化難以觀察的成本因素後，在零售環境中測試了上述檢查策略的有效性，發現其優於零售商的檢查程序和成熟的行業標準。最後，本文對如何優化分組和檢查決策進行說明，並顯示了優化群組構成的潛在效益。本文基於實證的建模工作產生了有關提升庫存準確度的可遷移方法和概括性見解。

Despite numerous optimization techniques proposed to address inventory record inaccuracy (IRI), there continues to be a lack of empirical appreciation of IRI, nor do existing item-level inspection policies accommodate managerial needs for allocating inspection effort to groups of items. We address these issues by collaborating with a retailer to collect archival data and develop statistical estimation and practical optimization techniques that address IRI. We propose a continuous-time model to explain group-level information decay and, based on the model's structure, develop an inspection policy that satisfies managerial needs for allocating inspection effort to a group of items. After analyzing model behavior and quantifying unobservable cost factors using information readily available, we test the efficacy of the proposed policy within the retailing environment and find it to outperform both the retailer's inspection routines and a well-established industry benchmark. Finally, we illustrate how to optimize grouping and inspection decisions jointly and show potential benefits from optimized group formation. Our empirically grounded modeling effort yields transferable methods and generalizable insights for improving inventory integrity.

參考文獻：Chuang, H. H.-C., Oliva, R., & Kumar, S. (2022). Group-level information decay and inventory inspection: An empirical-analytical approach. Journal of Operations Management, 68(2), 130-152. https://doi.org/10.1002/joom.1167

2.在運營效率和生產率的測量中考慮跨地區技術異質性

出於對理解區位因素如何影響企業績效的長期興趣，本文提供了一個半參數方法來探討生產分析中的區位異質性。本文所用方法的新穎性在於通過允許投入彈性和生產率參數作為企業地理位置的未知函數，並運用局部核方法對其進行估計，明確地模擬了生產函數估計中參數的空間變化。這既允許生產技術在空間上存在差異，從而將鄰近地區對企業生產的影響納入考量，也可檢驗跨地區差異對企業間運營生產率差異影響作用。本文所述模型優於其他空間生產函數模型，因為它（1）明確估計了生產函數中的跨地區差異，（2）易與傳統生產原則相協調，更重要的是，（3）可以通過構建常用的代理變量方法從數據中識別出來，本文將其擴展到包含位置異質性。本文運用上述方法對中國的化學品製造業進行研究，發現技術差異（相對於獨特的的企業異質性差異）是該行業總生產率跨地區差異的主要來源。

Motivated by the long-standing interest in understanding the role of location for firm performance, this paper provides a semiparametric methodology to accommodate locational heterogeneity in production analysis. Our approach is novel in that we explicitly model spatial variation in parameters in the production-function estimation. We accomplish this by allowing both the input-elasticity and productivity parameters to be unknown functions of the firm's geographic location and estimate them via local kernel methods. This allows the production technology to vary across space, thereby accommodating neighborhood influences on firm production. In doing so, we are also able to examine the role of cross-location differences in explaining the variation in operational productivity among firms. Our model is superior to the alternative spatial production-function formulations because it (i) explicitly estimates the cross-locational variation in production functions, (ii) is readily reconcilable with the conventional production axioms and, more importantly, (iii) can be identified from the data by building on the popular proxy-variable methods, which we extend to incorporate locational heterogeneity. Using our methodology, we study China's chemicals manufacturing industry and find that differences in technology (as opposed to in idiosyncratic firm heterogeneity) are the main source of the cross-location differential in total productivity in this industry.

參考文獻：Malikov, E., Zhang, J., Zhao, S., & Kumbhakar, S. C. (2022). Accounting for cross-location technological heterogeneity in the measurement of operations efficiency and productivity. Journal of Operations Management, 68(2), 153-184. https://doi.org/10.1002/joom.1166

3.以標準化同儕指導促進護理過渡：採用隨機對照試驗的干預性研究

本文對經歷改變人生的大手術（如腎移植）後，患者在醫院和家庭之間轉移護理時如何共同創造價值進行了研究。本文通過與美國一家大型醫院的醫療服務提供者合作，採用干預性研究方法讓曾經的患者在出院後對現在的患者進行為期30天的輔導，以開發標準化的同儕指導計劃。此項研究招募了80名移植患者，並通過隨機對照試驗評估了該計劃對患者焦慮和30天內再入院的影響。對患者焦慮的分析結果發現，治療組的患者在30天內焦慮評分多下降了3.42分，這表明導師輔導的護理過渡降低了患者的焦慮水平。對（患者30天內）再入院的分析發現，治療組的患者在頭30天內再次入院的風險是對照組的12.6倍。探索性分析表明，再入院率的提高可能是由於患者能更早報告併發症，這使其得以更早得到治療。總體上，此項研究為醫療保健業務如何利用具有成本效益的資源設計有效的護理過渡計劃和使用以患者為中心的指標提供了建議和見解。

We investigate how patients can co-create value when transitioning care between the hospital and home after a major life altering surgery such as kidney transplant. Collaborating with health care providers at a large U.S. hospital, we adopted an intervention-based research approach to develop a standardized peer-mentoring program where former patients mentor current patients for 30 days postdischarge. We assessed the impact of the program on patient anxiety and 30-day readmissions through a randomized control trial that recruited 80 transplant patients. Our analyses of patient anxiety indicated that patients in the treatment arm experienced 3.42 points greater decrease in anxiety score over 30 days, suggesting that care transitions using mentors decreases anxiety levels among patients. Our analyses of readmissions led to an unexpected but explainable result. We found that patients in the treatment arm were at 12.6 times greater risk of readmission during the first 30 days. Exploratory analysis suggests that increased readmission may have been due to patients reporting complications sooner, which allowed them to get treated earlier. Overall, our study informs healthcare operations on how to design effective transition of care programs using cost-effective resources and offers new insights on using patient-centric metrics.

參考文獻：Chun, Y., Harris, S. L., Chandrasekaran, A., & Hill, K. (2022). Improving care transitions with standardized peer mentoring: Evidence from intervention based research using randomized control trial. Journal of Operations Management, 68(2), 185-214. https://doi.org/10.1002/joom.1170