Disciplining deliberation: a sociotechnical perspective on machine learning trade-offs

This paper focuses on two highly publicized formal trade-offs in the field of responsible artificial intelligence (AI) -- between predictive accuracy and fairness and between predictive accuracy and interpretability. These formal trade-offs are often taken by researchers, practitioners, and policy-makers to directly imply corresponding tensions between underlying values. Thus interpreted, the trade-offs have formed a core focus of normative engagement in AI governance, accompanied by a particular division of labor along disciplinary lines. This paper argues against this prevalent interpretation by drawing attention to three sets of considerations that are critical for bridging the gap between these formal trade-offs and their practical impacts on relevant values. I show how neglecting these considerations can distort our normative deliberations, and result in costly and misaligned interventions and justifications. Taken together, these considerations form a sociotechnical framework that could guide those involved in AI governance to assess how, in many cases, we can and should have higher aspirations than the prevalent interpretation of the trade-offs would suggest. I end by drawing out the normative opportunities and challenges that emerge out of these considerations, and highlighting the imperative of interdisciplinary collaboration in fostering responsible AI

Creating a Tool to Reproducibly Estimate the Ethical Impact of Artificial Intelligence

How can an organization systematically and reproducibly measure the ethical impact of its AI-enabled platforms? Organizations that create applications enhanced by artificial intelligence and machine learning (AI/ML) are increasingly asked to review the ethical impact of their work. Governance and oversight organizations are increasingly asked to provide documentation to guide the conduct of ethical impact assessments. This document outlines a draft procedure for organizations to evaluate the ethical impacts of their work. We propose that ethical impact can be evaluated via a principles-based approach when the effects of platforms’ probable uses are interrogated through informative questions, with answers scaled and weighted to produce a multi-layered score. We initially assess ethical impact as the summed score of a project’s potential to protect human rights. However, we do not suggest that the ethical impact of platforms is assessed exclusively through preservation of human rights alone, a decidedly difficult concept to measure. Instead, we propose that ethical impact can be measured through a similar procedure assessing conformity with other important principles such as: protection of decisional autonomy, explainability, reduction of bias, assurances of algorithmic competence, or safety. In this initial draft paper, we demonstrate the application of our method for ethical impact assessment to the principles of human rights and bias

Developing Unit Cell Design Guidelines for Meso-scale Periodic Cellular Materials

Periodic cellular materials can have superior mechanical effective properties such as higher stiffness, strength, and/or flexibility compared to other materials with similar density. There is a significant body of research focusing on designing meso scale periodic cellular material structures with superior effective elastic properties; however, there is only limited research on how to guide designers on developing improved unit cell topologies and shapes, for a given set of loading requirements and conditions. To address this challenge, this dissertation introduces unit cell design guidelines. The guidelines codify design knowledge to provide direction and recommendations to engineers who are trying to change the topology and shape of unit cells to improve a targeted measure of performance. The guidelines investigate the effects of changes to topology and shape characteristics of unit cells subjected to in-plane shear loading. The investigated topology and shape characteristics include side connections, transverse connections, curved beams, and vertical legs. In order to validate that the unit cell design guidelines apply to a variety of unit cells with similar topology characteristics, each guideline is applied to a variety of unit cells and numerical simulations are used to validate that the performance of the unit cell is improved by the change. More importantly, this dissertation introduces a formalized and systematic method to develop unit cell design guidelines to achieve desired mechanical effective properties of a meso scale periodic cellular materials by changing the topology and shape of a unit cell. In order to support unambiguous discussion of cellular topology, a vocabulary is developed to describe two-dimensional periodic cellular materials. The vocabulary represents the 2D periodic cellular materials through descriptions of the unit cell and of the tiling of the unit cell arrangements. A designer study is conducted to evaluate the usability of the vocabulary by engineers. The results of designer study support the idea that the vocabulary is usable by engineers who generally do not have a background in periodic cellular materials. Two user studies are conducted to evaluate the effect of subjectivity and sequencing of the guidelines. The subjectivity results show that the modified unit cells developed by different engineers using the same guideline and initial topology have similarities. However, the degree of similarity is affected by the content of the guidelines, how the guidelines are written, and the initial unit cells. The sequencing of guidelines is also investigated to evaluate if changing the order of guidelines affects modified unit cells. Ultimately, the guidelines are validated through numerical simulations and controlled studies with human subjects while the guideline development method is demonstrated through one case study with novice engineer developing new guidelines under tension loading

Locally finitely presented Grothendieck categories and the pure semisimplicity conjecture

In this paper, we investigate locally finitely presented pure semisimple (hereditary) Grothendieck categories. We show that every locally finitely presented pure semisimple (resp., hereditary) Grothendieck category A is equivalent to the category of left modules over a left pure semisimple (resp., left hereditary) ring when Mod(fp(A)) is a QF-3 category and every representable functor in Mod(fp(A)) has finitely generated essential socle. In fact, we show that there exists a bijection between Morita equivalence classes of left pure semisimple (resp., left hereditary) rings $\Lambda$ and equivalence classes of locally finitely presented pure semisimple (resp., hereditary) Grothendieck categories A that Mod(fp(A)) is a QF-3 category and every representable functor in Mod(fp(A)) has finitely generated essential socle. To prove this result, we study left pure semisimple rings by using Auslander's ideas. We show that there exists, up to equivalence, a bijection between the class of left pure semisimple rings and the class of rings with nice homological properties. These results extend the Auslander and Ringel-Tachikawa correspondence to the class of left pure semisimple rings. As a consequence, we give several equivalent statements to the pure semisimplicity conjecture

The rigidity of filtered colimits of n-cluster tilting subcategories

Let $\Lambda$ be an artin algebra and $\mathcal{M}$ be an n-cluster tilting subcategory of $\Lambda$-mod with $n\ge 2$. From the viewpoint of higher homological algebra, a question that naturally arose in [17] is when $\mathcal{M}$ induces an n-cluster tilting subcategory of $\Lambda$-Mod. In this paper, we answer this question and explore its connection to Iyama's question on the finiteness of n-cluster tilting subcategories of $\Lambda$-mod. In fact, our theorem reformulates Iyama's question in terms of the vanishing of Ext; and highlights its relation with the rigidity of filtered colimits of $\mathcal{M}$. Also, we show that Add$(\mathcal{M})$ is an n-cluster tilting subcategory of $\Lambda$-Mod if and only if Add$(\mathcal{M})$ is a maximal n-rigid subcategory of $\Lambda$-Mod if and only if $\lbrace X\in \Lambda$-Mod$~|~ {\rm Ext}^i_{\Lambda}(\mathcal{M},X)=0 ~~~ {\rm for ~all}~ 0<i<n \rbrace \subseteq {\rm Add}(\mathcal{M})$ if and only if $\mathcal{M}$ is of finite type if and only if ${\rm Ext}_{\Lambda}^1({\underrightarrow{\lim}}\mathcal{M}, {\underrightarrow{\lim}}\mathcal{M})=0$. Moreover, we present several equivalent conditions for Iyama's question which shows the relation of Iyama's question with different subjects in representation theory such as purity and covering theory

Community detection forecasts material failure in a sheared granular material

The stability of a granular material is a collective phenomenon controlled by individual particles through their interactions. Forecasting when granular materials will undergo an abrupt failure is an ongoing challenge due to the intricate interactions between particles. Here, we report experiments on photoelastic disks undergoing intermittent stick-slip dynamics in a quasi-2D annular shear apparatus, with the evolving network of contact forces made visible via polarized light. We characterize the system by interpreting the interparticle forces as a multilayer network, and apply GenLouvin community detection to identify strongly correlated groups of particles. We observe that the community structure becomes increasingly volatile as the material approaches failure, and that this volatility provides a forecast that precedes what is detectable by considering the forces alone. We additionally observe that both weak and strong forces contribute to the strength of this forecast. These findings provide a new approach to detect patterns of causality and forecast impending failures

Image analysis methods in the measurement of ice loads on structures

The icing of marine vessels and offshore structures causes significant reductions in their efficiency and creates unsafe working conditions. Ice detection and removal play important roles to reduce the risk of hazards and increase operational efficiency. Ice detection and measurement on structures are a challenge in marine industries, due to a lack of studies in this field. In this research, image processing methods are developed to measure ice loads on structures. Image processing algorithms are used to detect the ice accumulated on the structures and then the ice loads are calculated. The combination of thermal and visual imaging is suggested to detect ice, in order to reduce drawbacks occurring in these types of imaging. Also, the ice load is calculated on a known structure based on the structure information and the ice detection results. Experiments are conducted to verify the results of ice load measurements obtained by the algorithms. Ice loads are calculated in a variety of situations, such as using different imaging types, changing camera positions and angles of view and using different ice load values. The calculated ice load results show good coherence with the actual values obtained by measuring the samples which are used in the experimental setups