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  1. This special issue includes papers from some of the leading competitors in the ASSISTments Longitudinal Data Mining Competition 2017, as well as some research from non-competitors, using the same data set. In this competition, participants attempted to predict whether students would choose a career in a STEM field or not, making this prediction using a click-stream dataset from middle school students working on math assignments inside ASSISTments, an online tutoring platform. At the conclusion of the competition on December 3rd, 2017, there were 202 participants, 74 of whom submitted predictions at least once. In this special issue, some of themore »leading competitors present their results and what they have learned about the link between behavior in online learning and future STEM career development.« less
  2. The use of computer-based systems in classrooms has provided teachers with new opportunities in delivering content to students, supplementing instruction, and assessing student knowledge and comprehension. Among the largest benefits of these systems is their ability to provide students with feedback on their work and also report student performance and progress to their teacher. While computer-based systems can automatically assess student answers to a range of question types, a limitation faced by many systems is in regard to open-ended problems. Many systems are either unable to provide support for open-ended problems, relying on the teacher to grade them manually, ormore »avoid such question types entirely. Due to recent advancements in natural language processing methods, the automation of essay grading has made notable strides. However, much of this research has pertained to domains outside of mathematics, where the use of open-ended problems can be used by teachers to assess students’ understanding of mathematical concepts beyond what is possible on other types of problems. This research explores the viability and challenges of developing automated graders of open-ended student responses in mathematics. We further explore how the scale of available data impacts model performance. Focusing on content delivered through the ASSISTments online learning platform, we present a set of analyses pertaining to the development and evaluation of models to predict teacher-assigned grades for student open responses.« less
  3. Sensor-free affect detectors can detect student affect using their activities within intelligent tutoring systems or other online learning environments rather than using sensors. This technology has made affect detection more scalable and less invasive. However, existing detectors are either interpretable but less accurate (e.g., classical algorithms such as logistic regression) or more accurate but uninterpretable (e.g., neural networks). We investigate the use of a new type of neural networks that are monotonic after the first layer for affect detection that can strike a balance between accuracy and interpretability. Results on a real- world student affect dataset show that monotonic neuralmore »networks achieve comparable detection accuracy to their non-monotonic counterparts while offering some level of interpretability.« less
  4. There is a long history of research on the development of models to detect and study student behavior and affect. Developing computer-based models has allowed the study of learning constructs at fine levels of granularity and over long periods of time. For many years, these models were developed using features based on previous educational research from the raw log data. More recently, however, the application of deep learning models has often skipped this feature-engineering step by allowing the algorithm to learn features from the fine-grained raw log data. As many of these deep learning models have led to promising results,more »researchers have asked which situations may lead to machine-learned features performing better than expert-generated features. This work addresses this question by comparing the use of machine-learned and expert-engineered features for three previously-developed models of student affect, off-task behavior, and gaming the system. In addition, we propose a third feature-engineering method that combines expert features with machine learning to explore the strengths and weaknesses of these approaches to build detectors of student affect and unproductive behaviors.« less
  5. We present and evaluate a machine learning based system that automatically grades audios of students speaking a foreign language. The use of automated systems to aid the assessment of student performance holds great promise in augmenting the teacher’s ability to provide meaningful feedback and instruction to students. Teachers spend a significant amount of time grading student work and the use of these tools can save teachers a significant amount of time on their grading. This additional time could be used to give personalized attention to each student. Significant prior research has focused on the grading of closed-form problems, open-ended essaysmore »and textual content. However, little research has focused on audio content that is much more prevalent in the language-study education. In this paper, we explore the development of automated assessment tools for audio responses in a college-level Chinese language-learning course. We analyze several challenges faced while working with data of this type as well as the generation and extraction of features for the purpose of building machine learning models to aid in the assessment of student language learning.« less
  6. Because Chinese reading and writing systems are not phonetic, Mandarin Chinese learners must construct six-way mental connections in order to learn new words, linking characters, meanings, and sounds. Little research has focused on the difficulties inherent to each specific component involved in this process, especially within digital learning environments. The present work examines Chinese word acquisition within ASSISTments, an online learning platform traditionally known for mathematics education. Students were randomly assigned to one of three conditions in which researchers manipulated a learning assignment to exclude one of three bi-directional connections thought to be required for Chinese language acquisition (i.e., sound-meaningmore »and meaning-sound). Researchers then examined whether students’ performance differed significantly when the learning assignment lacked sound-character, character-meaning, or meaning-sound connection pairs, and whether certain problem types were more difficult for students than others. Assessment of problems by component type (i.e., characters, meanings, and sounds) revealed support for the relative ease of problems that provided sounds, with students exhibiting higher accuracy with fewer attempts and less need for system feedback when sounds were included. However, analysis revealed no significant differences in word acquisition by condition, as evidenced by next-day post-test scores or pre- to post-test gain scores. Implications and suggestions for future work are discussed.« less
  7. There is a long history of research on the development of models to detect and study student behavior and affect. Developing computer-based models has allowed the study of learning constructs at fine levels of granularity and over long periods of time. For many years, these models were developed using features based on previous educational research from the raw log data. More recently, however, the application of deep learning models has often skipped this feature engineering step by allowing the algorithm to learn features from the fine-grained raw log data. As many of these deep learning models have led to promisingmore »results, researchers have asked which situations may lead to machine-learned features performing better than expert-generated features. This work addresses this question by comparing the use of machine-learned and expert-engineered features for three previously-developed models of student affect, off-task behavior, and gaming the system. In addition, we propose a third feature-engineering method that combines expert features with machine learning to explore the strengths and weaknesses of these approaches to build detectors of student affect and unproductive behaviors.« less
  8. We present and evaluate a machine learning based system that automatically grades audios of students speaking a foreign language. The use of automated systems to aid the assessment of student performance holds great promise in augmenting the teacher’s ability to provide meaningful feedback and instruction to students. Teachers spend a significant amount of time grading student work and the use of these tools can save teachers a significant amount of time on their grading. This additional time could be used to give personalized attention to each student. Significant prior research has focused on the grading of closed-form problems, open-ended essaysmore »and textual content. However, little research has focused on audio content that is much more prevalent in language study education. In this paper, we explore the development of automated assessment tools for audio responses in a college-level Chinese language-learning course. We analyze several challenges faced while working with data of this type as well as the generation and extraction of features for the purpose of building machine learning models to aid in the assessment of student language learning.« less
  9. Online learning environments allow for the implementation of psychometric scales on diverse samples of students participating in authentic learning tasks. One such scale, the Intrinsic Motivation Inventory (IMI) can be used to inform stakeholders of students’ subjective motivational and regulatory styles. The IMI is a multidimensional scale developed in support of Self-Determination Theory [1, 2, 3], a strongly validated theory stating that motivation and regulation are moderated by three innate needs: autonomy, belonging, and competence. As applied to education, the theory posits that students who perceive volition in a task, those who report stronger connections with peers and teachers, andmore »those who perceive themselves as competent in a task are more likely to internalize the task and excel. ASSISTments, an online mathematics platform, is hosting a series of randomized controlled trials targeting these needs to promote integrated learning. The present work supports these studies by attempting to validate four subscales of the IMI within ASSISTments. Iterative factor analysis and item reduction techniques are used to optimize the reliability of these subscales and limit the obtrusive nature of future data collection efforts. Such scale validation efforts are valuable because student perceptions can serve as powerful covariates in differentiating effective learning interventions.« less