title: A study of hierarchical and flat classification of proteins

authors: Zimek, Arthur

subjects: computer science

abstract: Automatic classification of proteins using machine learning is an important problem that has received significant attention in the literature. One feature of this problem is that expert-defined hierarchies of protein classes exist and can potentially be exploited to improve classification performance. In this article we investigate empirically whether this is the case for two such hierarchies. We compare multi-class classification techniques that exploit the information in those class hierarchies and those that do not, using logistic regression, decision trees, bagged decision trees, and support vector machines as the underlying base learners. In particular, we compare hierarchical and flat variants of ensembles of nested dichotomies. The latter have been shown to deliver strong classification performance in multi-class settings. We present experimental results for synthetic, fold recognition, enzyme classification, and remote homology detection data. Our results show that exploiting the class hierarchy improves performance on the synthetic data, but not in the case of the protein classification problems. Based on this we recommend that strong flat multi-class methods be used as a baseline to establish the benefit of exploiting class hierarchies in this area.

text: A study of hierarchical and flat classification of proteins Automatic classification of proteins using machine learning is an important problem that has received significant attention in the literature. One feature of this problem is that expert-defined hierarchies of protein classes exist and can potentially be exploited to improve classification performance. In this article we investigate empirically whether this is the case for two such hierarchies. We compare multi-class classification techniques that exploit the information in those class hierarchies and those that do not, using logistic regression, decision trees, bagged decision trees, and support vector machines as the underlying base learners. In particular, we compare hierarchical and flat variants of ensembles of nested dichotomies. The latter have been shown to deliver strong classification performance in multi-class settings. We present experimental results for synthetic, fold recognition, enzyme classification, and remote homology detection data. Our results show that exploiting the class hierarchy improves performance on the synthetic data, but not in the case of the protein classification problems. Based on this we recommend that strong flat multi-class methods be used as a baseline to establish the benefit of exploiting class hierarchies in this area.

year: 2008

title: Impact of running first year and final year electronics laboratory classes in parallel

authors: Scott, Jonathan B.

subjects: electronics laboratory

abstract: First electronics courses are considered difficult by students because of the circuit theory content, and retention of students in electronics is a problem worldwide. Retention is especially problematic at universities that offer a common first-year program since the students can change streams, for example from Electrical to Mechanical. At our university we ran the laboratory classes for a challenging first-year electronics course in the same room at the same time as a popular final-year mechatronics class that involved visible use of Lego Mindstorms, a model elevator, digital model trains and slot cars, etc. We report the outcomes of a quantitative and qualitative study of the impact of this organisation. One lab stream did not see the parallel classes and thus acted as a control group.

text: Impact of running first year and final year electronics laboratory classes in parallel First electronics courses are considered difficult by students because of the circuit theory content, and retention of students in electronics is a problem worldwide. Retention is especially problematic at universities that offer a common first-year program since the students can change streams, for example from Electrical to Mechanical. At our university we ran the laboratory classes for a challenging first-year electronics course in the same room at the same time as a popular final-year mechatronics class that involved visible use of Lego Mindstorms, a model elevator, digital model trains and slot cars, etc. We report the outcomes of a quantitative and qualitative study of the impact of this organisation. One lab stream did not see the parallel classes and thus acted as a control group.

year: 2010

title: COVID-19 and blind spaces: Responding to digital (in)accessibility and social isolation during lockdown for blind, deafblind, low vision, and vision impaired persons in Aotearoa New Zealand

authors: Graham, Rebekah Sarah

abstract: In this chapter we, as Indigenous (Māori) and non-Indigenous (Pākehā) academics, practitioners, and disability advocates critically examine the experiences of people who are blind, deafblind, low vision and vision impaired (BLV) during the COVID-19 lockdown of Aotearoa New Zealand. We pay particular attention to the ways in which access (or lack thereof) to digital spaces facilitated experiences of social inclusion (and exclusion). Digital connectivity was heavily relied upon during lockdown in Aotearoa New Zealand to disseminate health information and to connect people socially. The use of digital technologies during lockdown extended the interpersonal space of the home beyond the physicality of the urban home people were confined to, drawing people together across the country and creating a sense of shared experience. However, these experiences were not shared equally across the citizenry. Conversations during lockdown with disability advocates and practitioners working with BLV persons identified that. For example, the government website on COVID19 was initially inaccessible for BLV persons and there were assumptions of digital accessibility and literacy within the domestic space of the home. Taken together, these exacerbated existing inequities for BLV persons, some of whom experience multiple domains of exclusion (for example, Indigenous BLV persons with reduced access to services and for whom English is their second language). Drawing on Lefebvre’s (1991) work on the dialectics of space and Lewin’s (1936/2013) construction of the life-space, we consider the interplay of space and experience with regards to the digital and physical space(s) available and inhabited during the shared social experience of lockdown. We discuss possibilities for co-creating socially inclusive (digital) spaces of belonging that reflect and refract life-space relational connections across social groups. Our reflections on the lockdown experience include opportunities post-pandemic for policy makers and practitioners to address digital accessibility inequities.

text: COVID-19 and blind spaces: Responding to digital (in)accessibility and social isolation during lockdown for blind, deafblind, low vision, and vision impaired persons in Aotearoa New Zealand In this chapter we, as Indigenous (Māori) and non-Indigenous (Pākehā) academics, practitioners, and disability advocates critically examine the experiences of people who are blind, deafblind, low vision and vision impaired (BLV) during the COVID-19 lockdown of Aotearoa New Zealand. We pay particular attention to the ways in which access (or lack thereof) to digital spaces facilitated experiences of social inclusion (and exclusion). Digital connectivity was heavily relied upon during lockdown in Aotearoa New Zealand to disseminate health information and to connect people socially. The use of digital technologies during lockdown extended the interpersonal space of the home beyond the physicality of the urban home people were confined to, drawing people together across the country and creating a sense of shared experience. However, these experiences were not shared equally across the citizenry. Conversations during lockdown with disability advocates and practitioners working with BLV persons identified that. For example, the government website on COVID19 was initially inaccessible for BLV persons and there were assumptions of digital accessibility and literacy within the domestic space of the home. Taken together, these exacerbated existing inequities for BLV persons, some of whom experience multiple domains of exclusion (for example, Indigenous BLV persons with reduced access to services and for whom English is their second language). Drawing on Lefebvre’s (1991) work on the dialectics of space and Lewin’s (1936/2013) construction of the life-space, we consider the interplay of space and experience with regards to the digital and physical space(s) available and inhabited during the shared social experience of lockdown. We discuss possibilities for co-creating socially inclusive (digital) spaces of belonging that reflect and refract life-space relational connections across social groups. Our reflections on the lockdown experience include opportunities post-pandemic for policy makers and practitioners to address digital accessibility inequities.

year: 2021