本研究旨在探討基於基因演算法(genetic algorithm)在同時考量先備知識水平及學習角色異質互補，以及社會互動關係同質因素下，發展之最佳化問題導向網路合作學習分組策略，是否有助於提升問題導向網路合作學習之學習成效、互動關係、團體效能與團體凝聚力。 本研究採用準實驗研究法，以新北市某國小六年級三個不同班級合計83名學生為研究對象，並將三個班級學生隨機分派為採用基因演算法最佳化分組策略的實驗組，以及分別採用隨機分組及學生自行選擇分組策略的控制組一與控制組二，三組學習者皆在問題導向學習系統（Problem-based learning system,簡稱PBL）上進行不同分組策略之問題導向網路合作學習活動。藉由學習成效與團體效能與團體凝聚力評量，以及分析三組學習者在問題導向學習系統上的學習歷程與互動關係，最後再輔以半結構式訪談，以驗證三種不同分組策略在學習成效、互動關係、團體效能與團體凝聚力上的差異。 結果顯示本研究所提出之最佳化問題導向網路合作學習分組策略具有提升學習成效之效益；本研究所提出之最佳化分組策略對於促進問題導向網路合作學習之同儕互動具有正面效益；採用不同問題導向網路合作學習分組策略組別學習者在團體效能與團體凝聚力上具有顯著差異；採用最佳化分組策略組別學習者在問題導向網路合作學習的滿意度接近同意的水準。 / This study aims to explore whether the optimized group formation scheme based on genetic algorithm helps students enhance learning performance, interaction, collective efficacy, and group cohesion in collaborative problem-based learning environment. Factors associated with heterogeneous complementation of students’ prior knowledge levels and learning roles and the homogeneity of social interaction relationship were simultaneously considered in the genetic algorithm-based optimized group formation scheme. In this paper, a quasi-experimental research method is employed to assess the effects of three different group formation schemes on the learning performance, interaction, collective efficacy, and group cohesion in collaborative problem-based learning environment. Eighty-three students in three different sixth-grade classes in an elementary school in New Taipei City were invited to participant in the experiment and were randomly divided into three groups: the experimental group, which adopts genetic algorithm-based optimized group formation scheme, and two control groups, one is randomly grouped; while the other allows students group themselves. Learners in these three groups all use collaborative problem-based learning system (CPBL) to perform collaborative problem-based learning activities. Learning performance, interaction, group efficacy and group cohesion evaluation are applied to analyze the learning process and interaction among learners in these three groups. Finally, a semi-structured interview is supplemented to validate the variation of these three different group formation schemes in learning performance, interaction, group efficacy and cohesion. The result showed that the genetic algorithm-based optimized group formation scheme helps students promote learning performance and provides positive effects on peer interaction in collaborative problem-based learning. Three group learners adopting different group formation schemes for collaborative problem-based learning show significant difference on group effectiveness and group cohesion. The satisfaction of learners adopting genetic algorithm-based optimized group formation scheme for collaborative problem-based learning reached a nearly agreed standard.

隨著資訊科技的發展，數位學習的觀念逐漸興起，在二十一世紀強調知識經濟的今天，自主學習及問題解決能力的養成更顯重要，而藉由網路進行問題導向合作學習，學習者可更方便的透過自主學習方式培養問題解決能力。然而學習者在進行網路合作學習的互動期間會接收到大量來自同儕的資訊，有些學習者常會因為無法判斷資訊的正確性，而無法有效選擇、判斷、分析與整合所獲得的資訊，進而觀望同儕或是意見領袖的意見。因此，本研究利用學習者在問題導向網路合作學習歷程中所產生的社會網路互動資料，利用品質Q函數結合基因算法進行社群探勘，並搭配PageRank演算法找尋出每個社群中的較意見領袖，探討採用教師直接進行資訊傳播的一級資訊傳播模式與透過社群意見領袖進行資訊傳播的二級資訊傳播模式對於學習者的學習成效、社會網路互動及團體凝聚力的影響。此外，也探討採用這兩種資訊傳播模式的不同性別及不同人格特質學習者的學習成效、社會網路互動及團體凝聚力是否具有顯著差異。 研究結果發現：(1)在問題導向網路合作學習環境下，採用發佈訊息給意見領袖之二級資訊傳播模式的實驗組學習者，在學習成效上顯著優於教師透過網站公告之一級傳播模式的控制組學習者；(2)在問題導向網路合作學習環境下，採用發佈訊息給意見領袖之二級資訊傳播模式的實驗組女性學習者，在學習成效上顯著優於透過教師網站公告之一級資訊傳播模式的控制組女性學習者，但兩組男性學習者之間則無顯著差異；(3)在問題導向網路合作學習環境下，採用發佈訊息給意見領袖之二級資訊傳播模式的實驗組學習者，在促進同儕互動成效上顯著優於教師透過網站公告之一級傳播模式的控制組學習者;(4)透過品質Q函數結合基因演算法偵測社群，以及使用PageRank找尋社群意見領袖之方法，能精確的協助教師找到問題導向網路合作學習社群之意見領袖。 最後，根據研究結果，本研究提出教學實施及未來研究方向建議，供後續研究參考以進行更深入的探究。 / The concept of e-learning gradually emerges with the development of information technology. In the 21st century when knowledge economy is emphasized, the cultivation of self-directed learning and problem-solving ability becomes more important. Learners with problem-based cooperative learning through networks can more conveniently cultivate the problem-solving ability with self-directed learning. Nonetheless, learners would receive large amount of peer information during the network cooperative learning interaction; some learners therefore could not effectively select, judge, analyze, and integrated the acquired information by judging the accuracy of information to further observe the opinions of peers or opinion leaders. For this reason, learners’ social network interaction data generated in the problem-based network cooperative learning process are proceeded community mining by combining quality function Q and genetic algorithm, and PageRank algorithm is applied to search for the opinion leader in each community in order to discuss the effects of teachers directly proceeding first-order information communication model and second-order information communication model through community opinion leaders on learners’ learning outcome, social network interaction, and group cohesiveness. Furthermore, the effects of such two information communication models on learning outcome, social network interaction, and group cohesiveness of learners with different genders and personality traits are also investigated. The research findings show (1) learners in the experimental group with second-order information communication model by distributing information to opinion leaders, under the problem-based network cooperative learning environment, significantly outperform learners in the control group with first-order communication model through network announcement on the learning outcome; (2) female learners in the experimental group with second-order information communication model by distributing information to opinion leaders, under the problem-based network cooperative learning environment, present remarkably better learning outcome than female learners in the control group with first-order information communication model through network announcement, while no significant difference appears between male learners in both groups; (3) learners in the experimental group with second-order information communication model by distributing information to opinion leaders, under the problem-based network cooperative learning, notably show better peer interaction effectiveness than learners in the control group with first-order communication model through network announcement; and (4) combining quality function Q with genetic algorithm to detect community and applying PageRank to search for community opinion leaders could accurately assist teachers in finding out the problem-based network cooperative learning community opinion leaders. Finally, suggestions for teaching practice and future research, according to the research results, are proposed in this study for successive research.

潛水是網路社群中的普遍行為，並且潛水者常為網路社群中的多數，通常潛水者從社群中獲取得多，但卻貢獻得少，雖然對於整體社群無害，但對於網路社群的貢獻卻相當有限，無助於整體社群的發展與成長。因此，如何激發潛水者更積極參與互動討論，樂於貢獻一己之力，對於網路社群的發展甚為關鍵。特別是在數位學習環境中，更應該積極發展有效激發潛水者策略，以促進潛水者更積極參與社群互動討論的意願，提昇整體社群合作學習動力。而透過讓潛水者感受到自己參與社群互動的重要，提昇潛水者的社會知覺，是否有助於激發潛水者表現出更積極的互動行為，值得進行深入的探討。 因此，本研究基於提昇潛水者的社會知覺，於問題導向學習環境中發展「社會互動排名」與「學習夥伴推薦」激勵機制，以探究其對於激發潛水者在社群互動之「討論區與訊息區的文章張貼篇數及內容層次」、「四階段問題導向學習閱讀心得寫作成效」，以及學習社群中的「網路密度」、「網路直徑」、「中心度」。除此之外，也探究「外向－內向」、「人際和諧－人際問題」、「信任感－迫害感」等基本人格特質，是否與潛水者被激發與否的成效有關，進而歸納激發潛水者的具體有效策略。 研究結果顯示，具「社會互動排名」與「學習夥伴推薦」激勵機制之問題導向學習平台，對於提昇社群討論互動以及學習成效具有正向顯著效益；激勵機制確實能有效激發潛水者，降低潛水情形，並且實施激勵機制對於凝聚整體學習社群網絡亦具有正向的效用。 / Lurking is a common behavior in the network community, and lurkers often take the majority in the network community. They often get more from the community, but give less to it. To the whole community, although it doesn’t do any harm, the contribution they make to the network community is so limited, which can’t help the development and growth of the entire community. Therefore, it is quite crucial for the development of the network community about how to motivate the lurkers to participate in the interactive discussion and contribute to the community actively. Especially in the digital learning environment, it should actively develop the strategies to motivate the lurkers effectively, so as to promote the willingness of the lurkers to participate in the interactive discussion of the community more actively. In this way, it can improve the driving force of the cooperative learning in the community. It deserves deep exploration about whether it can help to motivate the lurkers to present more active behaviors in the interaction by making them feel important to participate in the community interaction and improving their social awareness. Therefore, based on the purpose of improving the social awareness of the lurkers, this study develops the motivation mechanism of “social interaction ranking” and ” learning partner recommendation” in the learning-oriented environment to explore the effects of motivating the lurkers in the community interaction, such as “the number and content levels of the articles posted in the forum and bulletin board”, “writing effects of the four-stage problem-based learning and reading”, as well as the “network density”, “network diameter” and “concentration” in the learning community. Besides, it also discusses whether the basic personality is correlated to the effect of motivating the lurkers, including “introversion-extraversion”, “interpersonal problems- interpersonal harmony”, “sense of persecution- sense of trust”, so as to further summarize the concrete and effective strategies of motivating the lurkers. The study results show the problem-based learning platform with the motivation mechanism of “social interaction ranking” and ” learning partner recommendation” show positive and significant benefits to improve the social discussion interaction and learning effect. Moreover, the motivation mechanism system is proven to motivate the lurkers and reduce the lurking situation effectively, and the practice of the motivation mechanism system has positive effect on the cohesion of the whole learning community.