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1. Building for ‘We’: Safety Settings for Couples with Memory Concerns

   https://doi.org/10.1145/3411764.3445071  

   McDonald, Nora ; Mentis, Helena M. ( January 2021 , Proceedings of the 2021 CHI Conference on Human Factors in Computing Systems)

   null (Ed.)

   Designing technologies that support the mutual cybersecurity and autonomy of older adults facing cognitive challenges requires close collaboration of partners. As part of research to design a Safety Setting application for older adults with memory loss or mild cognitive impairment (MCI), we use a scenario-based participatory design. Our study builds on previous findings that couples’ approach to memory loss was characterized by a desire for flexibility and choice, and an embrace of role uncertainty. We find that couples don't want a system that fundamentally alters their relationship and are looking to maximize self-surveillance competence and minimize loss of autonomy for their partners. All desire Safety Settings to maintain their mutual safety rather than designating one partner as the target of oversight. Couples are open to more rigorous surveillance if they have control over what types of activities trigger various levels of oversight. 

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2. Savings or Selection? Initial Spending Reductions in the Medicare Shared Savings Program and Considerations for Reform

   https://doi.org/10.1111/1468-0009.12468  

   McWILLIAMS, J. MICHAEL ; HATFIELD, LAURA A. ; LANDON, BRUCE E. ; CHERNEW, MICHAEL E. ( July 2020 , The Milbank Quarterly)

   Concerns have been raised about risk selection in the Medicare Shared Savings Program (MSSP). Specifically, turnover in accountable care organization (ACO) physicians and patient panels has led to concerns that ACOs may be earning shared‐savings bonuses by selecting lower‐risk patients or providers with lower‐risk panels.

   We find no evidence that changes in ACO patient populations explain savings estimates from previous evaluations through 2015. We also find no evidence that ACOs systematically manipulated provider composition or billing to earn bonuses.

   The modest savings and lack of risk selection in the original MSSP design suggest opportunities to build on early progress.

   Recent program changes provide ACOs with more opportunity to select providers with lower‐risk patients. Understanding the effect of these changes will be important for guiding future payment policy.

   The Medicare Shared Savings Program (MSSP) establishes incentives for participating accountable care organizations (ACOs) to lower spending for their attributed fee‐for‐service Medicare patients. Turnover in ACO physicians and patient panels has raised concerns that ACOs may be earning shared‐savings bonuses by selecting lower‐risk patients or providers with lower‐risk panels.

   We conducted three sets of analyses of Medicare claims data. First, we estimated overall MSSP savings through 2015 using a difference‐in‐differences approach and methods that eliminated selection bias from ACO program exit or changes in the practices or physicians included in ACO contracts. We then checked for residual risk selection at the patient level. Second, we reestimated savings with methods that address undetected risk selection but could introduce bias from other sources. These included patient fixed effects, baseline or prospective assignment, and area‐level MSSP exposure to hold patient populations constant. Third, we tested for changes in provider composition or provider billing that may have contributed to bonuses, even if they were eliminated as sources of bias in the evaluation analyses.

   MSSP participation was associated with modest and increasing annual gross savings in the 2012‐2013 entry cohorts of ACOs that reached $139 to $302 per patient by 2015. Savings in the 2014 entry cohort were small and not statistically significant. Robustness checks revealed no evidence of residual risk selection. Alternative methods to address risk selection produced results that were substantively consistent with our primary analysis but varied somewhat and were more sensitive to adjustment for patient characteristics, suggesting the introduction of bias from within‐patient changes in time‐varying characteristics. We found no evidence of ACO manipulation of provider composition or billing to inflate savings. Finally, larger savings for physician group ACOs were robust to consideration of differential changes in organizational structure among non‐ACO providers (eg, from consolidation).

   Participation in the original MSSP program was associated with modest savings and not with favorable risk selection. These findings suggest an opportunity to build on early progress. Understanding the effect of new opportunities and incentives for risk selection in the revamped MSSP will be important for guiding future program reforms.

    

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3. PVM: Efficient Shadow Paging for Deploying Secure Containers in Cloud-native Environment

   https://doi.org/10.1145/3600006.3613158  

   Huang, Hang ; Lai, Jiangshan ; Rao, Jia ; Lu, Hui ; Hou, Wenlong ; Su, Hang ; Xu, Quan ; Zhong, Jiang ; Zeng, Jiahao ; Wang, Xu ; et al ( October 2023 , ACM)

   In cloud-native environments, containers are often deployed within lightweight virtual machines (VMs) to ensure strong security isolation and privacy protection. With the growing demand for customized cloud services, third-party vendors are turning to infrastructure-as-a-service (IaaS) cloud providers to build their own cloud-native platforms, necessitating the need to run a VM or a guest that hosts containers inside another VM instance leased from an IaaS cloud. State-of-the-art nested virtualization in the x86 architecture relies heavily on the host hypervisor to expose hardware virtualization support to the guest hypervisor, not only complicating cloud management but also raising concerns about an increased attack surface at the host hypervisor. This paper presents the design and implementation of PVM, a high-performance guest hypervisor for KVM that is transparent to the host hypervisor and assumes no hardware virtualization support. PVM leverages two key designs: 1) a minimal shared memory region between the guest and guest hypervisor to facilitate state transition between different privilege levels and 2) an efficient shadow page table design to reduce the cost of memory virtualization. PVM has been adopted by a major IaaS cloud provider for hosting tens of thousands of secure containers on a daily basis. Our experiments demonstrate that PVM significantly outperforms current nested virtualization in KVM for memory virtualization, particularly for concurrent workloads, while maintaining comparable performance in CPU and I/O virtualization. 

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4. Realizing Choice: Online Safeguards for Couples Adapting to Cognitive Challenges

   McDonald, Nora ; Larsen, Alison ; Battisti, Allison ; Madjaroff, Galina ; Massey, Aaron ; Mentis, Helena ( January 2020 , Sixteenth Symposium on Usable Privacy and Security ({SOUPS} 2020))

   This paper investigates qualitatively what happens when couples facing a spectrum of options must arrive at consensual choices together. We conducted an observational study of couples experiencing memory concerns (one or both) while the partners engaged in the process of reviewing and selecting “Safety Setting” options for online activities. Couples’ choices tended to be influenced by a desire to secure shared assets through mutual surveillance and a desire to preserve autonomy by granting freedom in social and personal activities. The availability of choice suits the uneven and unpredictable process of memory loss and couples’ acknowledged uncertainty about its trajectory, leading them to anticipate changing Safety Settings as one or both of them experience further cognitive decline. Reflecting these three decision drivers, we conclude with implications for a design system that offers flexibility and adaptability in variety of settings, accommodates the uncertainty of memory loss, preserves autonomy, and supports collaborative management of shared assets. 

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5. Approaches to Evidencing Intra-Team Equity in Student Collaborative Design Decision-Making Interactions

   Moffat, A. D. ; Fowler, R. R. ; Matz, R. L. ; JaQuay, S. ( June 2023 , American Society for Engineering Education)

   Team- and project-based pedagogies are increasingly normative in engineering education and beyond. Student teamwork holds the promise of developing collaborative skills deemed essential for new engineers by professional accreditation bodies such as ABET. The emphasis on these models, furthermore, reflects developments in pedagogical theory, stressing the importance of experiential learning and the social construction of knowledge, repositioning the instructor as a facilitator and guide. Teamwork in an educational context differs from that in professional contexts in that learning outcomes for all team members – both in terms of technical knowledge and team-working skills – are a primary goal of the activity, even while more tangible task-related outcomes might be the main concern of the students themselves. However, team-based learning also holds the potential for team members to have negative experiences, of which instructors may have little or no awareness, especially in real-time. Teams may achieve team-level outcomes required for successful completion, in spite of uneven levels of participation and contribution. Reduced participation on the part of an individual team member may have many causes, pro-active or reactive: it may be a deliberate refusal to engage, a lack of self-confidence, or a response to hostility from other members, among other possibilities. Inequitable team interactions will lead to uneven uptake of desired learning outcomes. Fostering equity in interactions and identifying inequitable practices among team members is therefore an important part of implementing team-based pedagogies, and an essential first step in identifying and challenging systematic patterns of inequity with regard to members of historically marginalized groups. This paper will therefore explore ways in which equity in group decision-making may be conceptualized and observed, laying the foundations for identifying and addressing inequities in the student experience. It will begin by considering different potential manifestations of interactional equity, surveying notions derived from prior education research in the fields of health, mathematics, engineering, and the natural sciences. These notions include: equity of participation on the basis of quantified vocal contributions (in terms of words, utterances, or clausal units); distribution and evolution of interactional roles; equity of idea endorsement and uptake; distribution of inchargeness and influence; equity of access to positional identities and discourse practices; and team member citizenship. In the paper’s empirical component, we trial measures of equity taken or developed from this literature on a small dataset of transcripts showing verbal interactions between undergraduate student team members in a first-year engineering design course. Some measures will be qualitative and others quantitative, depending on the particular form and manifestation of equity they are designed to examine. Measures include manual coding of speech acts and interactional ‘bids’, statistical measures of utterance frequency and length, and computational approaches to modeling interactional features such as social impact and receptivity. Results are compared with the students’ own reflections on the interactions, taken immediately afterward. Recommendations are made for the application of the measures, both from research and practice perspectives. Keywords: Teamwork, Equity, Interaction, Design 

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