Group Fairness in Prediction-Based Decision Making: From Moral Assessment to Implementation

Ensuring fairness of prediction-based decision making is based on statistical group fairness criteria. Which one of these criteria is the morally most appropriate one depends on the context, and its choice requires an ethical analysis. In this paper, we present a step-by-step procedure integrating three elements: (a) a framework for the moral assessment of what fairness means in a given context, based on the recently proposed general principle of "Fair equality of chances" (FEC) (b) a mapping of the assessment's results to established statistical group fairness criteria, and (c) a method for integrating the thus-defined fairness into optimal decision making. As a second contribution, we show new applications of the FEC principle and show that, with this extension, the FEC framework covers all types of group fairness criteria: independence, separation, and sufficiency. Third, we introduce an extended version of the FEC principle, which additionally allows accounting for morally irrelevant elements of the fairness assessment and links to well-known relaxations of the fairness criteria. This paper presents a framework to develop fair decision systems in a conceptually sound way, combining the moral and the computational elements of fair prediction-based decision-making in an integrated approach. Data and code to reproduce our results are available at this https UR

Effect of high energy radiation on technical polymers

Fiber reinforced polymers (FRP) offer excellent fatigue resistance in combination with low specific weight. However, in contrast to metals, microscopic damage is usually present right from the beginning of cyclic loading and calls for insights on initiation and propagation. As with other properties, the overall performance of a composite is determined by its constituents namely fiber, matrix and fiber-matrix interface. Especially, the matrix polymer is supposedly responsible for damage initiation. To study this, different methods for altering the matrix properties can be used. The presented research makes use of Co-60 irradiation to modify the polymer on a molecular level. Six potential candidate materials for FRP are investigated, two thermoplastics and four thermosets. After irradiating the neat polymer samples with (30, 100, 200 and 500 kGy) the properties are investigated by quasi-static tensile tests and fatigue experiments. The resulting fractures are inspected visually. The results for thermoplastic materials show deteriorating tensile properties, whereas some of the thermosetting resins improve. Despite this, it could also be shown that deterioration in monotonic loading does not necessarily deteriorate the fatigue properties. The fracture surfaces indicate yielding as possible cause. Finally, it was shown that irradiation is a promising modification method for the investigation of composites and possible also a method to improve the fatigue performance

Enforcing Group Fairness in Algorithmic Decision Making: Utility Maximization Under Sufficiency

Binary decision making classifiers are not fair by default. Fairness requirements are an additional element to the decision making rationale, which is typically driven by maximizing some utility function. In that sense, algorithmic fairness can be formulated as a constrained optimization problem. This paper contributes to the discussion on how to implement fairness, focusing on the fairness concepts of positive predictive value (PPV) parity, false omission rate (FOR) parity, and sufficiency (which combines the former two). We show that group-specific threshold rules are optimal for PPV parity and FOR parity, similar to well-known results for other group fairness criteria. However, depending on the underlying population distributions and the utility function, we find that sometimes an upper-bound threshold rule for one group is optimal: utility maximization under PPV parity (or FOR parity) might thus lead to selecting the individuals with the smallest utility for one group, instead of selecting the most promising individuals. This result is counter-intuitive and in contrast to the analogous solutions for statistical parity and equality of opportunity. We also provide a solution for the optimal decision rules satisfying the fairness constraint sufficiency. We show that more complex decision rules are required and that this leads to within-group unfairness for all but one of the groups. We illustrate our findings based on simulated and real data

A protocol for orphan detection and termination in mobile agent systems

Orphan detection and termination in distributed systems is a well researched field for which many solutions exist. These solutions exploit well defined parent-child relationships given in distributed systems. But they are not applicable in mobile agent systems, since no similar natural relationship between agents exist. Thus new protocols have to be developed. In this paper one such protocol for orphan detection and agent termination is presented. First we present two approaches, the energy concept and the path concept. The energy concept is a passive termination protocol, and the path concept is a protocol for finding agents, that can be used to implement active termination. The energy' approach is based on the idea that an agent is provided with a limited amount of energy, which can be spent in exchange for the resources used by the agent. From time to time the agent has to request additional energy from its creator. The agent is terminated as soon as the energy falls to 0. This approach to agent termination implicitly implements orphan detection, i.e. if the creator has terminated, the dependent agents are killed as soon as they have no energy left. The path' approach uses a chain of proxies. As soon as an agent leaves a location, a proxy is created that points to the new location. By following the chain of proxies, the path, one can find any agent, and consequently terminate it. Both approaches have disadvantages. By merging them on different levels we create a protocol that combines the advantages of both approaches, and at the same time minimizes the disadvantages. The shadow' approach uses the idea of a placeholder (shadow) which is assigned by the agent system to each new agent. The shadow records the location of all dependent agents. Removing the root shadow implies that all dependent shadows and agents are terminated recursively

A comparison of mechanisms for locating mobile agents

In this paper we present different possible approaches for locating mobile agents and introduce a classification for them. We will use this classification to categorize mechanisms proposed in standards and implemented in mobile agent systems. Then we assess the different mechanisms regarding their fault tolerance, their message complexity and the migration delay they induce. We conclude by combining the different assessments to allow a comparison of all mechanisms

ATP binding to bovine serum albumin

AbstractSpecific binding or ATP to bovine serum albumin (BSA) is demonstrated employing ATP derivatives spin-labeled at either N6 or C8 of adenine ring or at the ribose moiety. Based on a 1:1 stoichiometry binding constants are in the 50–100 μM range. Binding is largely competitive with ATP or stearic acid. A small fraction of the labeled nucleotides could not be liberated by these ligands. Binding of AMP is in the millimolar range, only

Cisplatin-Based Chemotherapy for Pulmonary Metastasized Germ Cell Tumors of the Testis - Be Aware of Acute Respiratory Distress Syndrome

Background: Cisplatin-based combination chemotherapy is regarded as standard of care for patients with advanced germ cell tumors. In patients with lung metastases and a high tumor load, an association between induction chemotherapy and the development of a `tumor-associated' acute respiratory distress syndrome (ARDS) has been hypothesized. Case Report: We report the clinical course of a 19-year-old patient who rapidly developed fatal ARDS during the first cycle of chemotherapy using the PEI regimen (cisplatin, etoposide and ifosfamide) for a metastasized (lung, liver, lymph nodes) germ cell tumor of the testis. Conclusion: Further clinical research in order to better define risk factors for developing ARDS in this patient population as well as novel strategies for the prevention and treatment of ARDS in those patients are necessary

Distributive Justice as the Foundational Premise of Fair ML: Unification, Extension, and Interpretation of Group Fairness Metrics

Group fairness metrics are an established way of assessing the fairness of prediction-based decision-making systems. However, these metrics are still insufficiently linked to philosophical theories, and their moral meaning is often unclear. In this paper, we propose a comprehensive framework for group fairness metrics, which links them to more theories of distributive justice. The different group fairness metrics differ in their choices about how to measure the benefit or harm of a decision for the affected individuals, and what moral claims to benefits are assumed. Our unifying framework reveals the normative choices associated with standard group fairness metrics and allows an interpretation of their moral substance. In addition, this broader view provides a structure for the expansion of standard fairness metrics that we find in the literature. This expansion allows addressing several criticisms of standard group fairness metrics, specifically: (1) they are parity-based, i.e., they demand some form of equality between groups, which may sometimes be detrimental to marginalized groups; (2) they only compare decisions across groups but not the resulting consequences for these groups; and (3) the full breadth of the distributive justice literature is not sufficiently represented

The shadow approach : an orphan detection protocol for mobile agents

Orphan detection in distributed systems is a well researched field for which many solutions exist. These solutions exploit well defined parent-child relationships given in distributed systems. But they are not applicable in mobile agent systems, since no similar natural relationship between agents exist. Thus new protocols have to be developed. In this paper one such protocol for controlling mobile mobile agents and for orphan detection is presented. The shadow' approach presented in this paper uses the idea of a placeholder (shadow) which is assigned by the agent system to each new agent. This defines an artificial relationship between agents and shadow. The shadow records the location of all dependent agents. Removing the root shadow implies that all dependent agents are declared orphan and are eventually terminated. We introduce agent proxies that create a path from shadow to every agent. In an extension of the basic protocol we additionally allow the shadow to be mobile. The shadow approach can be used for termination of groups of agents even if the exact location of each single agent is not known