隨著人類文明的發展進步，各領域的知識越趨深入，造成知識爆炸，資訊迅速有效地取得變得非常重要。由於以前科技的發展常是增加研究深度，但發展至今廣度越來越受重視，如生物與資訊電子結合等等。也因為現代人白天必須工作，若想進一步進修學習，受限於時間、地點等，也沒有這麼方便。所以近年來開始發展的線上學習平台，變成為了現代人進修學習非常方便的管道。
現在有許多線上學習平台，並整合了許多便利的功能，例如: 線上討論區、線上討論室等等，讓大家也可以在線上進行討論。有非常多的線上學習平台，與世界各國知名的學校教授合作，開辦許多專業線上課程，讓現代人可以很便利迅速地學習不同領域的知識。由於線上課程提供了迅速、便利的學習管道，造成線上課程與實體課程規模差異巨大，如原本一位教授開課的修課人數最多可能百人，但線上課程卻可達上千人，且許多時候作業與考試的模式可能是申論式，但老師並無法批改這麼大量的作業或考試，使作業或考試的批改變的非常困難。
本論文之目的即為解決這個問題，提出同儕評分的做法，讓同儕互相評分，並於線上學習平台上進行實驗，以求較貼近專家評斷的結果。此作法除了可以解決老師在批改作業或考試的問題之外，也可讓同儕在評分過程中，再一次檢視自己學習的成果與盲點，提高學習成效。但也由於將原本需由老師批改的作業或考試，改由同儕互相評分，所以如何於同儕的評分結果獲得較為客觀的評分成績，便是本論文探討之目標。
線上學習系統越來越廣泛、功能越來越齊全，讓現代人面對知識、資訊爆炸的世代，也有便利的管道可以提升自己在不同方面的能力，促使科技文明再次進步。

With the appearance of a great amount of knowledge of different fields, the explosion of knowledge has taken place. How to get information quickly and efficiently has become extremely important. Furthermore, it is necessary for modern people to learn much more since the integration of different technologies in different fields has become more and more common; however, it is not convenient for modern people to learn due to the limit of time and place. Therefore, online learning platform has been a convenient way for learning in recent years.
There are many online learning platforms with a great number of convenient functions inclusive of online discussion forum, online face-to-face discussion room, and so on. Plenty of institutes developing online learning platforms cooperate with well-known professors all over the world, providing a good approach to learn knowledge in different fields. However, the grading tasks could be difficult for teachers since a great number of open-answer quizzes/assignments are needed to be assessed.
For the purpose of solving the assessment problem, we propose a peer grading approach and implement on the real online learning platform to do experiments to get a better assessment result which might be similar to the experts’ assessments. This mechanism not only solves the assessment problem, but also enhances the learning effectiveness of students by their review in the assessment process. Nevertheless, how to get an objective assessment by peer grading is the main topic in this thesis.
With the popularity of online learning platforms, we modern people can learn more and enhance our capabilities in a quick and convenient way when facing with the explosion of knowledge and information, and this will definitely promote the advancement in science and technology again.

Chapter 1 Introduction 1
Chapter 2 Related Works 3
2.1 Massive Open Online Courses 3
2.1.1 cMOOC 4
2.1.2 xMOOC 5
2.2 ShareCourse 5
Chapter 3 System Design and Architecture 9
3.1 System Architecture Overview 9
3.2 System Procedure 11
3.3 Design of Distributor 14
3.4 Design of Trust-Degree Updater 16
Chapter 4 Implementation and Experiment 18
4.1 Environment 18
4.1.1 Smarty Template System 19
4.1.2 CodeIgniter 20
4.2 Distributor Implementation 21
4.2.1 Distribution Flow Chart 22
4.2.2 Distribution Algorithm 25
4.3 Trust-Degree Updater Implementation 29
4.3.1 Trust-Degree Update Flow Chart 30
4.3.2 Trust-Degree Update Formula 34
4.3.3 Trust-Degree Update Algorithm 36
4.4 Experiment Results 39
Chapter 5 Conclusion and Future work 43
References 45

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