Optimal Design for Sequential Online Auctions with Multiple Units

拍賣是古老商業形式的一種，也是有效率的交易方式。隨著網際網路的大眾化，相較於傳統拍賣，線上拍賣已經是較有效率的交易方式。大多數的線上拍賣研究假設拍賣場數是單一的，但是這個假設是存在疑問的。事實上，單一個拍賣可以被分割成數個序列的拍賣。本研究基於Bapna, Goes, and Gupta(2002)的拍賣利益產生模式，設定兩個可控制參數，拍賣批量和拍賣增額，以達到最佳化拍賣利潤。 本研究用數值方法，來量化拍賣批量和拍賣增額在拍賣利潤上的影響。接下來，發展模式來分配各序列拍賣的批量，並解決動態規劃的問題。例子顯示在後期，最適批量是越來越低的。且最適批量隨著總拍賣人數上升而上升，最適拍賣增額隨著總拍賣人數上升而下降。最後本研究指出，相較於單一期數的拍賣，使用本模式分割存貨能增加利潤。本研究有助於改善拍賣參數的設計。Auction is one of the oldest type of commerce and the effective trade methods. As the popularity of the Internet grows, online auctions have been the efficient way of transaction relative to traditional auctions. Most of the online auction researches focus on the assumption that the number of auctions is single. However, this assumption is open to question. In fact, a single auction of the entire inventory can be split into sequential auctions of smaller lots. This study based on the revenue generating model (Bapna, Goes, and Gupta, 2002) uses two controllable parameters, lot size and bid increment, to maximize the profits of auctions. This study takes a numerical approach to quantify the effect of auction lot size and bid increment on the profits of auctions. Next, this study develops a model to allocate inventory across sequential auctions and solve the dynamic programming problem. The author uses numerical examples to show that the optimal lot size decreases from period to period. The author also demonstrates that the optimal lot size increases as the number of total bidders increases while the optimal bid increment decreases as the number of total bidders increases. Finally, this study also shows that using our model for splitting the inventory increases benefits relative to a single-period auction. This research is beneficial in improving the design of auction parameters.摘要 i ABSTRACT ii TABLE OF CONTENTS iii LIST OF TABLES iv LIST OF FIGURES v CHAPTER 1 INTRODUCTION 1 CHAPTER 2 LITERATURE REVIEW 4 2.1 Online Auctions 4 2.2 Bidder Behaviors and Strategies 6 2.3 Bid Increment and Lot Size 7 2.3 Sequential Auctions 8 CHAPTER 3 OPTIMIZATION OF MULTI-UNIT SEQUENTIAL AUCTIONS 10 3.1 Dynamic Program for Optimal Lot Size Policy 10 3.2 Revenue Determination 12 CHAPTER 4 MODEL SOLUTION APPROACH AND NUMERICAL ANALYSIS 17 4.1 Single Multi-unit Auction 17 4.2 Multiple Sequential Auctions 21 CHAPTER 5 CONCLUSION AND FUTURE WORK 26 REFERENCE 28 APPENDIX: The detailed derived process for expression (6) 30 Variation of the expected revenue for the larger number of total bidders 3

[[alternative]]The Physical Learn and Performance in Military Academy Students: The Moderating Effect of Flow Experience

[[abstract]]本研究旨在探討軍事院校學員的運動動機、運動資源及激勵制度對運動成效的影響，並以心流經驗作為干擾變數來加以探討。採用99學年度北部某軍事院校進修教育學員在訓練期間內的前測及後測做為初級資料，以區分士官高級班49名、士官長正規班53名、軍官正規班77名，共計179名做為研究對象，採用迴歸分析檢定研究假說，研究結果發現： （1）進修學員依不同運動動機，在運動成效上具有顯著的正向影響。 （2）進修學員依不同運動資源，在運動成效上具有顯著的正向影響。 （3）進修學員在單位中，激勵制度在運動成效上，未有顯著的正向影響。 （4）進修學員在運動動機、運動資源及激勵制度的交互作用對運動成效具有顯著的正向影響。 （5）心流經驗在軍事院校學員的運動動機、運動資源、激勵制度及運動成效具有顯著的正向影響。[[abstract]]The purpose of this research is to examine the influence of military academy students’ sport motivation, sport resource and motivation system on sport effectiveness, and explore the moderating effects of flow experience. Sample was chosen from pretest academic Year 99 in military academy students’, during training of pretest-posttest data was used to collect primary data, The data including 49 of non-commissioned officers advanced course, 53 of master chief regular classes and 77 of regular class officers. A total of 179 questionnaires were collected. Regression analysis was used to test the hypotheses. The findings were listed as follow:（1）Different sport motivation have a significantly positive influence on sport effectiveness of education students.（2）Different sport resource have a significantly positive influence on sport effectiveness of education students.（3）Motivation system have not a significantly positive influence on sport effectiveness of education students.（4）Sport motivation, sport resource and motivation system have a significantly positive influence of the interaction on sport effectiveness of education students.（5） Flow experience has a significantly positive influence of sport motivation, sport resource, motivation system and sport effectiveness of education students

以連續過熱壓力流體產製絞股藍皂的保健原料之方法

一種以連續過熱壓力流體產製絞股藍皂的保健原料之方法,主要針對絞股藍所含的絞股藍總皂進行萃取及純化分離,利用壓力水萃提製程,以批次與半連續式壓力流體萃取絞股藍總皂,並以樹脂純化粗萃液中的絞股藍總皂,改進現有的有機溶劑提取及純化方式,所衍生的人體危害及環境污染問題,為其特徵者