We propose the PeerRank method for peer assessment. This constructs a grade for an agent based on the grades proposed by the agents evaluating the agent. Since the grade of an agent is a measure of their ability to grade correctly, the PeerRank method weights grades by the grades of the grading agent. The PeerRank method also provides an incentive for agents to grade correctly. As the grades of an agent depend on the grades of the grading agents, and as these grades themselves depend on the grades of other agents, we define the PeerRank method by a fixed point equation similar to the PageRank method for ranking web-pages. We identify some formal properties of the PeerRank method (for example, it satisfies axioms of unanimity, no dummy, no discrimination and symmetry), discuss some examples, compare with related work and evaluate the performance on some synthetic data. Our results show considerable promise, reducing the error in grade predictions by a factor of 2 or more in many cases over the natural baseline of averaging peer grades.
Another work which is close to ours is the CrowdGrader mechanism for peer evaluation from UC Santa Cruz @cite_8 . CrowdGrader lets students submit and collaboratively grade solutions to homework assignments. The tool permitted both ranking and grading of homework. However, de Alfaro and Shavlovsky found that students much preferred to grade than to rank. They expressed uneasiness in ranking their peers, perceiving ranking as a blunt tool compared to grading. At the heart of CrowdGrader is the Vancouver algorithm for combining peer grades. In each iteration, this algorithm computes a consensus estimate of the grade of each submission, weighing grades according to the (estimated) accuracy of each student; the consensus estimates are then used to update the estimated accuracy of the students. The update attempts to minimize variance.
@cite_8
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Crowdsourcing offers a practical method for ranking and scoring large amounts of items. To investigate the algorithms and incentives that can be used in crowdsourcing quality evaluations, we built CrowdGrader, a tool that lets students submit and collaboratively grade solutions to homework assignments. We present the algorithms and techniques used in CrowdGrader, and we describe our results and experience in using the tool for several computer-science assignments. CrowdGrader combines the student-provided grades into a consensus grade for each submission using a novel crowdsourcing algorithm that relies on a reputation system. The algorithm iterativerly refines inter-dependent estimates of the consensus grades, and of the grading accuracy of each student. On synthetic data, the algorithm performs better than alternatives not based on reputation. On our preliminary experimental data, the performance seems dependent on the nature of review errors, with errors that can be ascribed to the reviewer being more tractable than those arising from random external events. To provide an incentive for reviewers, the grade each student receives in an assignment is a combination of the consensus grade received by their submissions, and of a reviewing grade capturing their reviewing effort and accuracy. This incentive worked well in practice. CrowdGrader is a system that lets students submit and collaboratively review and grade homework. We describe the techniques and ideas used in CrowdGrader, and report on the experience of using CrowdGrader in disciplines ranging from Computer Science to Economics, Writing, and Technology. In CrowdGrader, students receive an overall crowd-grade that reflects both the quality of their homework, and the quality of their work as reviewers. This creates an incentive for students to provide accurate grades and helpful reviews of other students' work. Instructors can use the crowd-grades as final grades, or fine-tune the grades according to their wishes. Our results on seven classes show that students actively participate in the grading and write reviews that are generally helpful to the submissions' authors. The results also show that grades computed by CrowdGrader are sufficiently precise to be used as the homework component of class grades. Students report that the main benefits in using CrowdGrader are the quality of the reviews they receive, and the ability to learn from reviewing their peers' work. Instructors can leverage peer learning in their classes, and easily handle homework evaluation in large classes. In massive open online courses (MOOCs), peer grading serves as a critical tool for scaling the grading of complex, open-ended assignments to courses with tens or hundreds of thousands of students. But despite promising initial trials, it does not always deliver accurate results compared to human experts. In this paper, we develop algorithms for estimating and correcting for grader biases and reliabilities, showing significant improvement in peer grading accuracy on real data with 63,199 peer grades from Coursera's HCI course offerings --- the largest peer grading networks analysed to date. We relate grader biases and reliabilities to other student factors such as student engagement, performance as well as commenting style. We also show that our model can lead to more intelligent assignment of graders to gradees. Peer and self-assessment offer an opportunity to scale both assessment and learning to global classrooms. This article reports our experiences with two iterations of the first large online class to use peer and self-assessment. In this class, peer grades correlated highly with staff-assigned grades. The second iteration had 42.9p of students’ grades within 5p of the staff grade, and 65.5p within 10p. On average, students assessed their work 7p higher than staff did. Students also rated peers’ work from their own country 3.6p higher than those from elsewhere. We performed three experiments to improve grading accuracy. We found that giving students feedback about their grading bias increased subsequent accuracy. We introduce short, customizable feedback snippets that cover common issues with assignments, providing students more qualitative peer feedback. Finally, we introduce a data-driven approach that highlights high-variance items for improvement. We find that rubrics that use a parallel sentence structure, unambiguous wording, and well-specified dimensions have lower variance. After revising rubrics, median grading error decreased from 12.4p to 9.9p. We have implemented a peer grading system for review of student assignments over the World Wide Web and used it in approximately eight courses in computing and electrical engineering. Students prepare their assignments and submit them to our Peer Grader (PG) system. Other students are then assigned to review and grade the assignments. The system allows authors and reviewers to communicate, with authors being able to update their submissions. Unique features of our approach include the ability to submit arbitrary sets of Web pages for review, and mechanisms for encouraging careful review of submissions. Electronic peer review facilitates collaborative learning in several ways. First, there is the obvious fact that students can learn from their reviewers' comments. Second, students help each other to improve their communication skills. Third, in team projects, peer review allows team members to be assessed by each other. Finally, peer review makes it possible to break up a large project into small chunks. In fact, new releases of PG are being developed in exactly this way. The need for automated grading tools for essay writing and open-ended assignments has received increasing attention due to the unprecedented scale of Massive Online Courses (MOOCs) and the fact that more and more students are relying on computers to complete and submit their school work. In this paper, we propose an efficient memory networks-powered automated grading model. The idea of our model stems from the philosophy that with enough graded samples for each score in the rubric, such samples can be used to grade future work that is found to be similar. For each possible score in the rubric, a student response graded with the same score is collected. These selected responses represent the grading criteria specified in the rubric and are stored in the memory component. Our model learns to predict a score for an ungraded response by computing the relevance between the ungraded response and each selected response in memory. The evaluation was conducted on the Kaggle Automated Student Assessment Prize (ASAP) dataset. The results show that our model achieves state-of-the-art performance in 7 out of 8 essay sets. We propose the PeerRank method for peer assessment. This constructs a grade for an agent based on the grades proposed by the agents evaluating the agent. Since the grade of an agent is a measure of their ability to grade correctly, the PeerRank method weights grades by the grades of the grading agent. The PeerRank method also provides an incentive for agents to grade correctly. As the grades of an agent depend on the grades of the grading agents, and as these grades themselves depend on the grades of other agents, we define the PeerRank method by a fixed point equation similar to the PageRank method for ranking web-pages. We identify some formal properties of the PeerRank method (for example, it satisfies axioms of unanimity, no dummy, no discrimination and symmetry), discuss some examples, compare with related work and evaluate the performance on some synthetic data. Our results show considerable promise, reducing the error in grade predictions by a factor of 2 or more in many cases over the natural baseline of averaging peer grades. Collaborative information filtering techniques play a key role in many Web 2.0 applications. While they are currently mainly used for business purposes such as product recommendation, collaborative filtering also has potential for usage in eLearning applications. The quality of a student provided solution can be heuristically determined by peers who review the solution, thus effectively disburdening the workload of tutors. This paper presents a collaborative filtering approach which is specifically designed for eLearning applications. A controlled lab study with the system confirmed that the underlying algorithm is suitable as a diagnostic tool: The system-generated quality heuristic correlated highly with an expert-provided manual grading of the student solutions. This was true independent of whether the students provided fine-grained or coarsegrained evaluations of peer solutions, and independent of the task type that the students worked on. Further, the system required only few peer evaluations in order to achieve an acceptable prediction quality. An automatic grading system is presented for grading assignments in scientific computing. A student can interactively use this system to check the correctness of his program assignments. The grade for a correct solution is automatically recorded. This paper also considers the security problems with such an automatic grading system. We describe Mechanical TA, an automated peer review system, and report on our experience using it over three years. Mechanical TA differs from many other peer review systems by involving human teaching assistants (TAs) as a way to assure review quality. Human TAs both evaluate the peer reviews of students who have not yet demonstrated reviewing proficiency and spot check the reviews of students who have. Mechanical TA also features "calibration" reviews, allowing students to quickly gain experience with the peer-review process. We used Mechanical TA for weekly essay assignments in a class of about 70 students, a course design that would have been impossible if every assignment had had to be graded by a TA. We show evidence that it helped to support student learning, leading us to believe that the system may also be useful to others. A system for automatic grading of programming assignments is described here. This grading system consists of a suite of Perl and Java programs, linked by a database, and driven by an interactive, user-grader controlled grading process. The rationale for the process, the process itself-and the process's interaction-with the programs, the database, and the user himself are discussed. This grading system has the ability to discover and accommodate unanticipated solutions by means of a grading process that is highly interactive with its user-the grader. It also has the ability to automatically accommodate a wide range of simple student errors, which can easily befuddle a more naive grading system. This system has been used since the Spring 2000 semester at Rutgers University, as a core part of the students' performance evaluation activities, in the Introduction to computer science course, where it routinely grades some 300-600 weekly assignments. Online labor markets, such as Amazon's Mechanical Turk, have been used to crowdsource simple, short tasks like image labeling and transcription. However, expert knowledge is often lacking in such markets, making it impossible to complete certain classes of tasks. In this work we introduce an alternative mechanism for crowdsourcing tasks that require specialized knowledge or skill: communitysourcing --- the use of physical kiosks to elicit work from specific populations. We investigate the potential of communitysourcing by designing, implementing and evaluating Umati: the communitysourcing vending machine. Umati allows users to earn credits by performing tasks using a touchscreen attached to the machine. Physical rewards (in this case, snacks) are dispensed through traditional vending mechanics. We evaluated whether communitysourcing can accomplish expert work by using Umati to grade Computer Science exams. We placed Umati in a university Computer Science building, targeting students with grading tasks for snacks. Over one week, 328 unique users (302 of whom were students) completed 7771 tasks (7240 by students). 80 of users had never participated in a crowdsourcing market before. We found that Umati was able to grade exams with 2 higher accuracy (at the same price) or at 33 lower cost (at equivalent accuracy) than traditional single-expert grading. Mechanical Turk workers had no success grading the same exams. These results indicate that communitysourcing can successfully elicit high-quality expert work from specific communities. Peer assessment is the most common approach to evaluating scientific work, and it is also gaining popularity for scaling evaluation of student work in large and distributed classes. The key idea is that each peer reviewer or grader rates a relatively small subset of the items, and that some method of manual, semi-automatic, or fully-automatic aggregation of all assessments defines the eventual rating of all items – the grade in peer grading, or whether to accept or reject a scientific manuscript. In this paper, we explore in how far a Bayesian Ordinal Peer Assessment (BOPA) method can provide additional decision support when making acceptance rejection decisions for a scientific conference. Using data from the 2015 ACM Conference on Knowledge Discovery and Data Mining (KDD), where this system was deployed, we discuss the potential merit of the BOPA approach compared to conventional decision support offered by the Microsoft Conference Management System (CMT). Three applications of computerized adaptive testing (CAT) to help solve problems encountered in educational settings are described and discussed. Each of these applications makes use of item response theory to select test questions from an item pool to estimate a student's achievement level and its precision. These estimates may then be used in conjunction with certain testing strategies to facilitate certain educational decisions. The three applications considered are (a) adaptive mastery testing for determining whether or not a student has mastered a particular content area, (b) adaptive grading for assigning grades to students, and (c) adaptive self-referenced testing for estimating change in a student's achievement level. Differences between currently used classroom procedures and these CAT procedures are discussed. For the adaptive mastery testing procedure, evidence from a series of studies comparing conventional and adaptive testing procedures is presented showing that the adaptive procedure results in more accurate mastery classifications than do conventional mastery tests, while using fewer test questions. This article describes a model and implementation of a system for automatically testing, evaluating, grading and providing critical feedback for submitted programming assignments. Complete automation of the evaluation process, with proper attention towards monitoring studentâ€™s progress and performing a finegrained analysis is addressed. The tool provides online support to both the instructors and students and is designed for service-oriented integration with a course management system using Web services. Rapid feedback is a core component of mastery learning, but feedback on open-ended work requires days or weeks in most classes today. This paper introduces PeerStudio, an assessment platform that leverages the large number of students' peers in online classes to enable rapid feedback on in-progress work. Students submit their draft, give rubric-based feedback on two peers' drafts, and then receive peer feedback. Students can integrate the feedback and repeat this process as often as they desire. In MOOC deployments, the median student received feedback in just twenty minutes. Rapid feedback on in-progress work improves course outcomes: in a controlled experiment, students' final grades improved when feedback was delivered quickly, but not if delayed by 24 hours. More than 3,600 students have used PeerStudio in eight classes, both massive and in-person. This research demonstrates how large classes can leverage their scale to encourage mastery through rapid feedback and revision. The growing prevalence of e-learning systems and on-line courses has made educational material widely accessible to students of varying abilities, backgrounds and styles. There is thus a growing need to accomodate for individual differences in such e-learning systems. This paper presents a new algorithm for personliazing educational content to students that combines collaborative filtering algorithms with social choice theory. The algorithm constructs a “difficulty” ranking over questions for a target student by aggregating the ranking of similar students, as measured by different aspects of their performance on common past questions, such as grades, number of retries, and time spent solving questions. It infers a difficulty ranking directly over the questions for a target student, rather than ordering them according to predicted performance, which is prone to error. The algorithm was tested on two large real world data sets containing tens of thousands of students and a million records. Its performance was compared to a variety of personalization methods as well as a non-personalized method that relied on a domain expert. It was able to significantly outperform all of these approaches according to standard information retrieval metrics. Our approach can potentially be used to support teachers in tailoring problem sets and exams to individual students and students in informing them about areas they may need to strengthen. In many settings, an effective way of evaluating objects of interest is to collect evaluations from dispersed individuals and to aggregate these evaluations together. Some examples are categorizing online content and evaluating student assignments via peer grading. For this data science problem, one challenge is to motivate participants to conduct such evaluations carefully and to report them honestly, particularly when doing so is costly. Existing approaches, notably peer-prediction mechanisms, can incentivize truth telling in equilibrium. However, they also give rise to equilibria in which agents do not pay the costs required to evaluate accurately, and hence fail to elicit useful information. We show that this problem is unavoidable whenever agents are able to coordinate using low-cost signals about the items being evaluated (e.g., text labels or pictures). We then consider ways of circumventing this problem by comparing agents' reports to ground truth, which is available in practice when there exist trusted evaluators---such as teaching assistants in the peer grading scenario---who can perform a limited number of unbiased (but noisy) evaluations. Of course, when such ground truth is available, a simpler approach is also possible: rewarding each agent based on agreement with ground truth with some probability, and unconditionally rewarding the agent otherwise. Surprisingly, we show that the simpler mechanism achieves stronger incentive guarantees given less access to ground truth than a large set of peer-prediction mechanisms. Pearson product–moment correlations found significant relationships between students' grades in the online class and their GPA, attendance at a class orientation session, the number of previous course withdrawals, ASSET reading scores, the number of previous online courses, age, and ACT English scores. Regression analysis found that two variables serve as the best predictors: attendance at an orientation session, and the student's grade point average. We introduce a new approach to the machine-assisted grading of short answer questions. We follow past work in automated grading by first training a similarity metric between student responses, but then go on to use this metric to group responses into clusters and subclusters. The resulting groupings allow teachers to grade multiple responses with a single action, provide rich feedback to groups of similar answers, and discover modalities of misunderstanding among students; we refer to this amplification of grader effort as “powergrading.” We develop the means to further reduce teacher effort by automatically performing actions when an answer key is available. We show results in terms of grading progress with a small “budget” of human actions, both from our method and an LDA-based approach, on a test corpus of 10 questions answered by 698 respondents.