Requirements are of paramount importance for the quality of software systems. Yet, requirements engineering education at universities is surprisingly hard. University students encounter difficulties in understanding the role of requirements and applying relevant methods to deal with requirements appropriately. One potential cause may be a lack of authenticity, i.e. settings that are too artificial to mirror the complexity of real-world situations adequately. This paper presents an innovative and integrated didactical approach for teaching requirements engineering that was devised in a goal- and competence-oriented manner to avoid some of these shortcomings, in particular by including requirements elicitation with real customers into an integrated didactic step-by-step approach. Obviously, requirements engineering education is far more than assembling technical knowledge. Rather, it involves many non-technical skills that obtain a specific flavor in requirements engineering. Our didactic approach also addresses these skills, while resting on a sound pedagogical underpinning. The paper also summarizes indications for the success of this approach, in particular by participants' self-evaluations.
{"title":"Experiences in Teaching and Learning Requirements Engineering on a Sound Didactical Basis","authors":"Yvonne Sedelmaier, D. Landes","doi":"10.1145/3059009.3059011","DOIUrl":"https://doi.org/10.1145/3059009.3059011","url":null,"abstract":"Requirements are of paramount importance for the quality of software systems. Yet, requirements engineering education at universities is surprisingly hard. University students encounter difficulties in understanding the role of requirements and applying relevant methods to deal with requirements appropriately. One potential cause may be a lack of authenticity, i.e. settings that are too artificial to mirror the complexity of real-world situations adequately. This paper presents an innovative and integrated didactical approach for teaching requirements engineering that was devised in a goal- and competence-oriented manner to avoid some of these shortcomings, in particular by including requirements elicitation with real customers into an integrated didactic step-by-step approach. Obviously, requirements engineering education is far more than assembling technical knowledge. Rather, it involves many non-technical skills that obtain a specific flavor in requirements engineering. Our didactic approach also addresses these skills, while resting on a sound pedagogical underpinning. The paper also summarizes indications for the success of this approach, in particular by participants' self-evaluations.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124486657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A pedagogical and technical HOW-TO for the git version control system, including administration, applications in class, for student collaboration, and assignment submission.
git版本控制系统的教学和技术指南，包括管理、课堂应用、学生协作和作业提交。
{"title":"GIT: Pedagogy, Use and Administration in Undergraduate CS","authors":"A. Rosenbloom, Sadia Sharmin, Andrew Wang","doi":"10.1145/3059009.3072980","DOIUrl":"https://doi.org/10.1145/3059009.3072980","url":null,"abstract":"A pedagogical and technical HOW-TO for the git version control system, including administration, applications in class, for student collaboration, and assignment submission.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126969357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Do students recognize the relationship between self-sufficient problem solving and exam performance? We explore this question based on log data and survey results collected over 3 semesters from 465 students who were split into cohorts based on final exam performance. Specifically, we consider three metrics: time on task, question difficulty, and self-efficacy ratings. Our results show that, on average, median values for time on task between Low and High performing cohorts are within 16%. However, increased question difficulty revealed very different modes of spending time: when working through practice tool exercises, the High cohort regularly attempted to solve problems without assistance, whereas the Low cohort frequently requested hints during initial and subsequent attempts. Overall, when re-attempting a question that was previously attempted but incorrect, slightly over 20% of the Low cohort were able to complete the question without using hints, whereas roughly 50% of the High cohort were able to do so. Most strikingly, as the semester progressed, the average increase in confidence to solve a similar question after viewing hints was greatest for students in the Low cohort. It appears that students among the Low cohort, who went on to fail the final exam, believed that viewing solutions to problems, instead of solving the problem on their own, adequately prepared them to be able to solve similar problems without assistance in the future.
{"title":"Study Habits, Exam Performance, and Confidence: How Do Workflow Practices and Self-Efficacy Ratings Align?","authors":"A. Estey, Y. Coady","doi":"10.1145/3059009.3059056","DOIUrl":"https://doi.org/10.1145/3059009.3059056","url":null,"abstract":"Do students recognize the relationship between self-sufficient problem solving and exam performance? We explore this question based on log data and survey results collected over 3 semesters from 465 students who were split into cohorts based on final exam performance. Specifically, we consider three metrics: time on task, question difficulty, and self-efficacy ratings. Our results show that, on average, median values for time on task between Low and High performing cohorts are within 16%. However, increased question difficulty revealed very different modes of spending time: when working through practice tool exercises, the High cohort regularly attempted to solve problems without assistance, whereas the Low cohort frequently requested hints during initial and subsequent attempts. Overall, when re-attempting a question that was previously attempted but incorrect, slightly over 20% of the Low cohort were able to complete the question without using hints, whereas roughly 50% of the High cohort were able to do so. Most strikingly, as the semester progressed, the average increase in confidence to solve a similar question after viewing hints was greatest for students in the Low cohort. It appears that students among the Low cohort, who went on to fail the final exam, believed that viewing solutions to problems, instead of solving the problem on their own, adequately prepared them to be able to solve similar problems without assistance in the future.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116047932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ayaan M. Kazerouni, S. Edwards, T. Hall, C. Shaffer
Good project management practices are hard to teach, and hard for novices to learn. Procrastination and bad project management practice occur frequently, and may interfere with successfully completing major programming projects in mid-level programming courses. Students often see these as abstract concepts that do not need to be actively applied in practice. Changing student behavior requires changing how this material is taught, and more importantly, changing how learning and practice are assessed. To provide proper assessment, we need to collect detailed data about how each student conducts their project development as they work on solutions. We present DevEventTracker, a system that continuously collects data from the Eclipse IDE as students program, giving us in-depth insight into students' programming habits. We report on data collected using DevEventTracker over the course of four programming projects involving 370 students in five sections of a Data Structures and Algorithms course over two semesters. These data support a new measure for how well students apply "incremental development" practices. We present a detailed description of the system, our methodology, and an initial evaluation of our ability to accurately assess incremental development on the part of the students. The goal is to help students improve their programming habits, with an emphasis on incremental development and time management.
{"title":"DevEventTracker: Tracking Development Events to Assess Incremental Development and Procrastination","authors":"Ayaan M. Kazerouni, S. Edwards, T. Hall, C. Shaffer","doi":"10.1145/3059009.3059050","DOIUrl":"https://doi.org/10.1145/3059009.3059050","url":null,"abstract":"Good project management practices are hard to teach, and hard for novices to learn. Procrastination and bad project management practice occur frequently, and may interfere with successfully completing major programming projects in mid-level programming courses. Students often see these as abstract concepts that do not need to be actively applied in practice. Changing student behavior requires changing how this material is taught, and more importantly, changing how learning and practice are assessed. To provide proper assessment, we need to collect detailed data about how each student conducts their project development as they work on solutions. We present DevEventTracker, a system that continuously collects data from the Eclipse IDE as students program, giving us in-depth insight into students' programming habits. We report on data collected using DevEventTracker over the course of four programming projects involving 370 students in five sections of a Data Structures and Algorithms course over two semesters. These data support a new measure for how well students apply \"incremental development\" practices. We present a detailed description of the system, our methodology, and an initial evaluation of our ability to accurately assess incremental development on the part of the students. The goal is to help students improve their programming habits, with an emphasis on incremental development and time management.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116236549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
While the market for the E-Discovery (Electronic Discovery) is predicted to grow rapidly in coming years, the anticipated shortage of electronic discovery professionals is a result of the lack of education programs in this emerging field. In this paper, an undergraduate minor program in electronic discovery is proposed based on the experience and accomplishment of an established computer forensics program at a public university. Not only will the new program meet the demand of a booming job market, it is also an inspiring practice in expanding computer science education to a non-programming-centric field.
{"title":"Designing an Undergraduate Minor Program in E-Discovery","authors":"Milton H. Luoma, Jigang Liu, K. Qian","doi":"10.1145/3059009.3072996","DOIUrl":"https://doi.org/10.1145/3059009.3072996","url":null,"abstract":"While the market for the E-Discovery (Electronic Discovery) is predicted to grow rapidly in coming years, the anticipated shortage of electronic discovery professionals is a result of the lack of education programs in this emerging field. In this paper, an undergraduate minor program in electronic discovery is proposed based on the experience and accomplishment of an established computer forensics program at a public university. Not only will the new program meet the demand of a booming job market, it is also an inspiring practice in expanding computer science education to a non-programming-centric field.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115862499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A key challenge for educators using online discussion forums is how to provide effective feedback and support to students, to ensure they are engaged with discussions on the forums, and do not disengage from the course. In addition, there is a significant problem of scale to address. Even relatively low population forums of less than a hundred students can generate thousands of posts, so it is infeasible for the lecturer to monitor every discussion to identify disengaging students. There is a need to understand the act of intervention, in order to provide automated tools to better assist teaching staff with this task. Measuring the impact of intervention can be challenging and requires us to, first, understand what ``standard'' behaviour looks like across different student groups and identify topics where intervention would be most effective. In this paper, we identify the impact of intervention on different groups of students, characterising their behaviour in terms of response time and activity, compare the different responses to programming-related questions and other questions, and identify the useful aspects of this study for computer science educators. We conduct an initial examination of the impact of the nature of the question on intervention effectiveness and propose an analysis method that can be applied to any computer science forum. we showcase the application of the method to three courses. Our results indicate that associating student activity with the number of forum posts is misleading, as students who are only reading the forums respond also to intervention.
{"title":"Understanding the Effects of Intervention on Computer Science Student Behaviour in On-line Forums","authors":"D. Vista, Nickolas J. G. Falkner, Claudia Szabo","doi":"10.1145/3059009.3059053","DOIUrl":"https://doi.org/10.1145/3059009.3059053","url":null,"abstract":"A key challenge for educators using online discussion forums is how to provide effective feedback and support to students, to ensure they are engaged with discussions on the forums, and do not disengage from the course. In addition, there is a significant problem of scale to address. Even relatively low population forums of less than a hundred students can generate thousands of posts, so it is infeasible for the lecturer to monitor every discussion to identify disengaging students. There is a need to understand the act of intervention, in order to provide automated tools to better assist teaching staff with this task. Measuring the impact of intervention can be challenging and requires us to, first, understand what ``standard'' behaviour looks like across different student groups and identify topics where intervention would be most effective. In this paper, we identify the impact of intervention on different groups of students, characterising their behaviour in terms of response time and activity, compare the different responses to programming-related questions and other questions, and identify the useful aspects of this study for computer science educators. We conduct an initial examination of the impact of the nature of the question on intervention effectiveness and propose an analysis method that can be applied to any computer science forum. we showcase the application of the method to three courses. Our results indicate that associating student activity with the number of forum posts is misleading, as students who are only reading the forums respond also to intervention.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121826400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Collaborative exams have shown promise for improving student learning in computing. Prior studies have focused on benefits for all students, whereas this study seeks to refine our understanding of which students benefit and how group composition impacts that benefit. Using a crossover experimental design, the study first investigates whether students from differing performance levels (low, medium, or high) benefit from the collaborative exam. We find that students in the middle of the class (neither high nor low performers) tend to benefit strongly from the collaborative exam. Second, we explore whether group composition based on performance levels impacts the performance of members of the group. The results suggest more homogeneous groups (i.e., students in the group are at similar performance levels) are beneficial whereas students in groups with high heterogeneity do not experience significant performance differences between the pre-test and post-test.
{"title":"Impact of Performance Level and Group Composition on Student Learning during Collaborative Exams","authors":"Yingjun Cao, Leo Porter","doi":"10.1145/3059009.3059024","DOIUrl":"https://doi.org/10.1145/3059009.3059024","url":null,"abstract":"Collaborative exams have shown promise for improving student learning in computing. Prior studies have focused on benefits for all students, whereas this study seeks to refine our understanding of which students benefit and how group composition impacts that benefit. Using a crossover experimental design, the study first investigates whether students from differing performance levels (low, medium, or high) benefit from the collaborative exam. We find that students in the middle of the class (neither high nor low performers) tend to benefit strongly from the collaborative exam. Second, we explore whether group composition based on performance levels impacts the performance of members of the group. The results suggest more homogeneous groups (i.e., students in the group are at similar performance levels) are beneficial whereas students in groups with high heterogeneity do not experience significant performance differences between the pre-test and post-test.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"221 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121464660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Elizabeth Vidal Duarte, Eveling Gloria Castro Gutierrez, Marco Aedo
Educators have long been trying to motivate students in their introductory programming courses. Games help students to practice formulas, facts and processes, motivating learning by adding fun. This work describes our experience in the use of Lightbot and the graphic library Turtle to introduce students to the concepts of algorithm and function. This approach has been implemented in two Universities in Arequipa. We present the assignments used in the first and second session of CS1. Our experience has shown us that students get a clear understanding of algorithm and functions that are later implemented with Python (Universidad La Salle) and Java (Universidad Nacional de San Agustin). We believe that the visual nature of games and the graphical component to teaching anything is more effective for students. Results were measured by students' perception in 2016.
长期以来，教育工作者一直试图在他们的编程入门课程中激励学生。游戏帮助学生练习公式、事实和过程，通过增加乐趣来激励学习。本作品描述了我们使用Lightbot和图形库Turtle的经验，向学生介绍算法和函数的概念。这一方法已在阿雷基帕的两所大学实施。我们将介绍CS1第一节和第二节课中使用的作业。我们的经验告诉我们，学生们对算法和函数有了清晰的理解，这些算法和函数后来用Python (universsidad La Salle)和Java (Universidad Nacional de San augustine)实现。我们相信，游戏的视觉本质和教学的图形组件对学生更有效。结果是通过2016年学生的感知来衡量的。
{"title":"When the Robot Meets the Turtle: A Gentle Introduction to Algorithms and Functions","authors":"Elizabeth Vidal Duarte, Eveling Gloria Castro Gutierrez, Marco Aedo","doi":"10.1145/3059009.3072974","DOIUrl":"https://doi.org/10.1145/3059009.3072974","url":null,"abstract":"Educators have long been trying to motivate students in their introductory programming courses. Games help students to practice formulas, facts and processes, motivating learning by adding fun. This work describes our experience in the use of Lightbot and the graphic library Turtle to introduce students to the concepts of algorithm and function. This approach has been implemented in two Universities in Arequipa. We present the assignments used in the first and second session of CS1. Our experience has shown us that students get a clear understanding of algorithm and functions that are later implemented with Python (Universidad La Salle) and Java (Universidad Nacional de San Agustin). We believe that the visual nature of games and the graphical component to teaching anything is more effective for students. Results were measured by students' perception in 2016.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"222 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122400804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Dee, Xefi Cufi, A. Milani, M. Marian, V. Poggioni, O. Aubreton, Anna Roura Rabionet, Tomi Rowlands
This paper describes a framework for successful interaction between universities and schools. It is common for computing academics interested in outreach (computer science evangelism) to work with local schools, particularly in countries where the computing curriculum in K-12 is new or underdeveloped. However it is rare for these collaborations to be ongoing, and for resources created through these school-university links to be shared beyond the immediate neighborhood. We have achieved this, through shared resources, careful evaluation, and cross-country collaboration. The activities themselves are inspired by ideas from the Lifelong Kindergarten group at MIT, emphasizing playful exploration of computational concepts and interdisciplinary working.
{"title":"Playfully Coding: Embedding Computer Science Outreach in Schools","authors":"H. Dee, Xefi Cufi, A. Milani, M. Marian, V. Poggioni, O. Aubreton, Anna Roura Rabionet, Tomi Rowlands","doi":"10.1145/3059009.3059038","DOIUrl":"https://doi.org/10.1145/3059009.3059038","url":null,"abstract":"This paper describes a framework for successful interaction between universities and schools. It is common for computing academics interested in outreach (computer science evangelism) to work with local schools, particularly in countries where the computing curriculum in K-12 is new or underdeveloped. However it is rare for these collaborations to be ongoing, and for resources created through these school-university links to be shared beyond the immediate neighborhood. We have achieved this, through shared resources, careful evaluation, and cross-country collaboration. The activities themselves are inspired by ideas from the Lifelong Kindergarten group at MIT, emphasizing playful exploration of computational concepts and interdisciplinary working.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"25 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132119320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Steve Cooper, S. Rodger, K. Isbister, M. Schep, RoxAnn H. Stalvey, L. Pérez
We offered professional development to in-service K-12 teachers. Teachers learned programming, and how to teach programming. During the subsequent academic year, they taught programming in their schools. We interviewed the teachers to better understand their experiences. This poster describes case studies of K-12 teachers as they teach programming for the first time. As this study is qualitative, it does not attempt to measure findings. Rather, in exploring individual teachers' experiences, we hope to benefit both future teachers who will need to teach computing as well as those who will be helping those teachers.
{"title":"K-12 Teachers Experiences with Computing: A Case Study","authors":"Steve Cooper, S. Rodger, K. Isbister, M. Schep, RoxAnn H. Stalvey, L. Pérez","doi":"10.1145/3059009.3072989","DOIUrl":"https://doi.org/10.1145/3059009.3072989","url":null,"abstract":"We offered professional development to in-service K-12 teachers. Teachers learned programming, and how to teach programming. During the subsequent academic year, they taught programming in their schools. We interviewed the teachers to better understand their experiences. This poster describes case studies of K-12 teachers as they teach programming for the first time. As this study is qualitative, it does not attempt to measure findings. Rather, in exploring individual teachers' experiences, we hope to benefit both future teachers who will need to teach computing as well as those who will be helping those teachers.","PeriodicalId":174429,"journal":{"name":"Proceedings of the 2017 ACM Conference on Innovation and Technology in Computer Science Education","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132201162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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