OER Knowledge CloudThesisÇelik, BerkanMassive Open Online Courses (MOOCs) have made a great progress around the world in the recent years. Bilgeİş Online Learning Portal (bilgeis.net) is one of the most comprehensive MOOC portals providing pdMOOCs (Massive Open Online Courses for Professional Development) for any learner who would like to enroll in an online course in Turkey. This study provides overall understanding and exploration of presage, process, and product variables and the relationships between these variables using a variety of data sources in Bilgeİş pdMOOCs based on Biggs' 3P model of teaching and learning, and intention-behavior gap in pdMOOCs using a mixed methods research with the explanatory sequential mixed methods design. In particular, the purpose of this study is four folds. The first is to examine the motivations for enrolling in the pdMOOCs, pdMOOC completion rates based on different perspectives, and the relationship between relevant variables and pdMOOC completion. The second is to examine learner intentions with subsequent behaviors (intention-behavior gap) and explain the reasons behind intention-behavior gap. The third is to examine course satisfaction and perceived learning in MOOCs with respect to online learning readiness and perceived usability variables. The last is to explore the reasons for not starting, not completing, and completing the pdMOOCs, online learning readiness, course satisfaction, factors affecting learning, portal usability, and perceived benefits obtained from the courses. A total of four pdMOOCs (two for technical skills and two for soft skills) were selected for this study using a three stage sampling strategy. The participants were learners from these four pdMOOCs, and the number of participants was 12,666 and 704 for the quantitative stage and qualitative stage, respectively. The data were collected using quantitative and qualitative instruments, and analyzed using descriptive and inferential statistics. The results showed that learners in Bilgeİş pdMOOCs have diverse motivations including learning a new topic, personal development, increasing current knowledge, and interest in the topic. The main reason why learners did not start and complete pdMOOCs was learner related time issues. Moreover, completion rates based on traditional completion rates, active learners, and learner intentions showed very different percentages. pdMOOC completion was significantly associated with age, gender, education level, employment status,learner intent, self-directed learning dimension of online learning readiness, and learners' course behaviors, but not with previous online learning experience. The results also showed that intention-behavior gap occurs in pdMOOCs, and the main reason behind intention-behavior gap was learner related time issues. The results indicated a significant relationship between online learning readiness, course satisfaction and perceived learning, online learning readiness and course satisfaction, and perceived usability and perceived learning. In addition, learners were mostly feeling themselves ready for online learning in pdMOOCs. They were mainly satisfied with the course design, and the course design related issues influenced their learning positively. They also found the portal easy to use and well-designed. They mainly obtained knowledge benefits from the pdMOOCs. The results of the study were further discussed, and practical suggestions for MOOC designers and developers, and MOOC providers were given.Massive Open Online Courses (MOOCs) have made a great progress around the world in the recent years. Bilgeİş Online Learning Portal (bilgeis.net) is one of the most comprehensive MOOC portals providing pdMOOCs (Massive Open Online Courses for Professional Development) for any learner who would like to enroll in an online course in Turkey. This study provides overall understanding and exploration of presage, process, and product variables and the relationships between these variables using a variety of data sources in Bilgeİş pdMOOCs based on Biggs' 3P model of teaching and learning, and intention-behavior gap in pdMOOCs using a mixed methods research with the explanatory sequential mixed methods design. In particular, the purpose of this study is four folds. The first is to examine the motivations for enrolling in the pdMOOCs, pdMOOC completion rates based on different perspectives, and the relationship between relevant variables and pdMOOC completion. The second is to examine learner intentions with subsequent behaviors (intention-behavior gap) and explain the reasons behind intention-behavior gap. The third is to examine course satisfaction and perceived learning in MOOCs with respect to online learning readiness and perceived usability variables. The last is to explore the reasons for not starting, not completing, and completing the pdMOOCs, online learning readiness, course satisfaction, factors affecting learning, portal usability, and perceived benefits obtained from the courses. A total of four pdMOOCs (two for technical skills and two for soft skills) were selected for this study using a three stage sampling strategy. The participants were learners from these four pdMOOCs, and the number of participants was 12,666 and 704 for the quantitative stage and qualitative stage, respectively. The data were collected using quantitative and qualitative instruments, and analyzed using descriptive and inferential statistics. The results showed that learners in Bilgeİş pdMOOCs have diverse motivations including learning a new topic, personal development, increasing current knowledge, and interest in the topic. The main reason why learners did not start and complete pdMOOCs was learner related time issues. Moreover, completion rates based on traditional completion rates, active learners, and learner intentions showed very different percentages. pdMOOC completion was significantly associated with age, gender, education level, employment status,learner intent, self-directed learning dimension of online learning readiness, and learners' course behaviors, but not with previous online learning experience. The results also showed that intention-behavior gap occurs in pdMOOCs, and the main reason behind intention-behavior gap was learner related time issues. The results indicated a significant relationship between online learning readiness, course satisfaction and perceived learning, online learning readiness and course satisfaction, and perceived usability and perceived learning. In addition, learners were mostly feeling themselves ready for online learning in pdMOOCs. They were mainly satisfied with the course design, and the course design related issues influenced their learning positively. They also found the portal easy to use and well-designed. They mainly obtained knowledge benefits from the pdMOOCs. The results of the study were further discussed, and practical suggestions for MOOC designers and developers, and MOOC providers were given.20202020/09EnglishEnglishMiddle East Technical University472Turkeyyesmassive open online coursesMOOCmassive open online courses for professional developmentpdMOOCBilgeİşBilgeİş Online Learning Portal12625905.pdfTurkey, Asia