Beyond A/B Testing: Sequential Randomization for Developing Interventions in Scaled Digital Learning Environments

Randomized experiments ensure robust causal inference that are critical to effective learning analytics research and practice. However, traditional randomized experiments, like A/B tests, are limiting in large scale digital learning environments. While traditional experiments can accurately compare two treatment options, they are less able to inform how to adapt interventions to continually meet learners' diverse needs. In this work, we introduce a trial design for developing adaptive interventions in scaled digital learning environments -- the sequential randomized trial (SRT). With the goal of improving learner experience and developing interventions that benefit all learners at all times, SRTs inform how to sequence, time, and personalize interventions. In this paper, we provide an overview of SRTs, and we illustrate the advantages they hold compared to traditional experiments. We describe a novel SRT run in a large scale data science MOOC. The trial results contextualize how learner engagement can be addressed through inclusive culturally targeted reminder emails. We also provide practical advice for researchers who aim to run their own SRTs to develop adaptive interventions in scaled digital learning environments

High-sensitivity troponin I concentrations are a marker of an advanced hypertrophic response and adverse outcomes in patients with aortic stenosis

Aims: High-sensitivity cardiac troponin I (cTnI) assays hold promise in detecting the transition from hypertrophy to heart failure in aortic stenosis. We sought to investigate the mechanism for troponin release in patients with aortic stenosis and whether plasma cTnI concentrations are associated with long-term outcome. Methods and results: Plasma cTnI concentrations were measured in two patient cohorts using a high-sensitivity assay. First, in the Mechanism Cohort, 122 patients with aortic stenosis (median age 71, 67% male, aortic valve area 1.0 ± 0.4 cm2) underwent cardiovascular magnetic resonance and echocardiography to assess left ventricular (LV) myocardial mass, function, and fibrosis. The indexed LV mass and measures of replacement fibrosis (late gadolinium enhancement) were associated with cTnI concentrations independent of age, sex, coronary artery disease, aortic stenosis severity, and diastolic function. In the separate Outcome Cohort, 131 patients originally recruited into the Scottish Aortic Stenosis and Lipid Lowering Trial, Impact of REgression (SALTIRE) study, had long-term follow-up for the occurrence of aortic valve replacement (AVR) and cardiovascular deaths. Over a median follow-up of 10.6 years (1178 patient-years), 24 patients died from a cardiovascular cause and 60 patients had an AVR. Plasma cTnI concentrations were associated with AVR or cardiovascular death HR 1.77 (95% CI, 1.22 to 2.55) independent of age, sex, systolic ejection fraction, and aortic stenosis severity. Conclusions: In patients with aortic stenosis, plasma cTnI concentration is associated with advanced hypertrophy and replacement myocardial fibrosis as well as AVR or cardiovascular death

'I would rather die': reasons given by 16-year-olds for not continuing their study of mathematics

Improving participation rates in specialist mathematics after the subject ceases to be compulsory at age 16 is part of government policy in England. This article provides independent and recent support for earlier findings concerning reasons for non- participation, based on free response and closed items in a questionnaire with a sample of over 1500 students in 17 schools, close to the moment of choice. The analysis supports findings that perceived difficulty and lack of confidence are important reasons for students not continuing with mathematics, and that perceived dislike and boredom, and lack of relevance, are also factors. There is a close relationship between reasons for non-participation and predicted grade, and a weaker relation to gender. An analysis of the effects of schools, demonstrates that enjoyment is the main factor differentiating schools with high and low participation indices. Building on discussion of these findings, ways of improving participation are briefly suggested

Cardiac Troponin Mutations and Restrictive Cardiomyopathy

Mutations in sarcomeric proteins have recently been established as heritable causes of Restrictive Cardiomyopathy (RCM). RCM is clinically characterized as a defect in cardiac diastolic function, such as, impaired ventricular relaxation, reduced diastolic volume and increased end-diastolic pressure. To date, mutations have been identified in the cardiac genes for desmin, α-actin, troponin I and troponin T. Functional studies in skinned muscle fibers reconstituted with troponin mutants have established phenotypes consistent with the clinical findings which include an increase in myofilament Ca2+ sensitivity and basal force. Moreover, when RCM mutants are incorporated into reconstituted myofilaments, the ability to inhibit the ATPase activity is reduced. A majority of the mutations cluster in specific regions of cardiac troponin and appear to be mutational “hot spots”. This paper highlights the functional and clinical characteristics of RCM linked mutations within the troponin complex

Academic achievement : the role of praise in motivating students

The motivation of students is an important issue in higher education, particularly in the context of the increasing diversity of student populations. A social-cognitive perspective assumes motivation to be dynamic, context-sensitive and changeable, thereby rendering it to be a much more differentiated construct than previously understood. This complexity may be perplexing to tutors who are keen to develop applications to improve academic achievement. One application that is within the control of the tutor, at least to some extent, is the use of praise. Using psychological literature the article argues that in motivating students, the tutor is not well served by relying on simplistic and common sense understandings of the construct of praise and that effective applications of praise are mediated by students' goal orientations, which of themselves may be either additive or interactive composites of different objectives and different contexts

Promoting a Growth Mindset in CS1: Does One Size Fit All? A Pilot Study

This paper describes a pilot intervention conducted in CS1, in theacademic year of 2016-2017. The intervention was based on thework of Dweck, promoting a growth Mindset in an effort to in-crease performance in introductory programming. The study alsoexamined data from a previous year (as a control group) to compareand contrast the results. Multiple factors related to programmingperformance were recorded with the control and treatment group,which were measured at multiple intervals throughout the course,to monitor changes as the pilot intervention was implemented.This study found a significant increase in programming perfor-mance when the intervention was deployed. However, althoughperformance increased for the treatment group, the average Mindsetdid not significantly change towards a growth Mindset (replicatingthe findings of Cutts et al, 2010). To further explore this finding,a preliminary deeper investigation using k-means clustering wascarried out. The investigation found that the intervention promoteda growth Mindset for some student profiles and a fixed Mindset forothers. This finding is important for educators considering interven-tion development or implementation of Mindset, and demonstratesthat a Mindset intervention may not be suitable for all learners

I doubt very seriously whether anyone will hire me; factors predicting employability perceptions in higher education

Understanding what makes people feel employable is enhanced by studying both the structural and individual dimensions of human behaviour. This paper examines the relative impact of three variables on perceptions of the employability of students in Higher Education (18–25); the way in which students think about themselves (mindset), their ability to overcome adversity (resilience) and the relationships and values that govern their interactions (social capital). It is reported that perceptions of employability are predicted largely by two subscales of the CD-RISC scale; “support” (p < .01, ηp2 = .07) and, “goal orientation” (p < .01 ηp2 = .29) and social capital “bridging” (P < .01, ηp2 = .05). Whilst mindset had no direct effect on perceived employability, both the fixed and growth mindsets have significant roles to play in personal resilience. We argue that contrary to previous findings, having a fixed mindset possibly supports the building of self-trust, self-respect and an acceptance of why you may be different from others. Results suggest that developing goal-oriented attitudes in students will support stronger beliefs about the extent to which they are employable.Published onlin