In this paper, missing attribute values in incomplete data sets have three possible interpretations: lost values, attribute-concept values and ‘do not care’ conditions. For rule induction, we use characteristic sets and generalized maximal consistent blocks. Therefore, we apply six different approaches for data mining. As follows from our previous experiments, where we used an error rate evaluated by ten-fold cross validation as the main criterion of quality, no approach is universally the best. Thus, we decided to compare our six approaches (...) using complexity of rule sets induced from incomplete data sets. We show that the smallest rule sets are induced from incomplete data sets with attribute-concept values, while the most complicated rule sets are induced from data sets with lost values. The choice between interpretations of missing attribute values is more important than the choice between characteristic sets and generalized maximal consistent blocks. (shrink)

Amblyopia, or lazy eye, is a neurological vision disorder that studies have shown to affect two to five percent of the population. Current methods of treatment produce the best visual outcome, if the condition is identified early in the patient's life. Several early screening procedures are aimed at finding the condition while the patient is a child, including an automated vision screening system. This paper aims to use artificial intelligence techniques to automatically identify children who are at risk for developing (...) the amblyopic condition and should therefore be referred to a specialist, i.e., pediatric ophthalmologist. Three techniques, namely, decision tree learning, random forest, and artificial neural network, are studied in this paper in terms of their effectiveness, using metrics of sensitivity, specificity, and accuracy. The features used by the techniques are extracted from images of patient eyes and are based on the color information. The efficacy of pixel color data is investigated with respect to the measurement of the rate of change of the color in the iris and pupil, i.e., color slope features. A 10-fold stratified cross validation procedure is used to compare the effectiveness of the three AI techniques in this medical application domain. (shrink)

In this paper incomplete data sets, or data sets with missing attribute values, have three interpretations, lost values, attribute-concept values and ‘do not care’ conditions. Additionally, the process of data mining is based on two types of probabilistic approximations, global and saturated. We present results of experiments on mining incomplete data sets using six approaches, combining three interpretations of missing attribute values with two types of probabilistic approximations. We compare our six approaches, using the error rate computed as a result (...) of ten-fold cross validation as a criterion of quality. We show that for some data sets the error rate is significantly smaller (5% level of significance) for lost values, for some data sets the smaller error rate is associated with attribute-concept values, and sometimes with ‘do not care’ conditions. Again, for some approaches the error rate is significantly smaller for saturated probabilistic approximations than for global probabilistic approximations, while for some approaches it is the other way around. Thus, for an incomplete data set, the best approach to data mining should be chosen by trying all six approaches. (shrink)

IN HIS NICOMACHEAN ETHICS, ARISTOTLE ARGUES THAT MOST DEATHS are contemptible and offer no opportunity for the exercise of virtue. Thomas Aquinas, on the other hand, considers the publicly shameful death of the martyr to be not only the highest exemplification of the virtue of courage but also the greatest proof of moral perfection more generally. What accounts for this substantial divergence from Aristotle on the possibility of virtuous action in death? This essay investigates the theologically informed metaphysical and anthropological (...) framework within which Aquinas situates his claims and then explores the implications of these claims for his broader ethical appropriation of Aristotelian virtue theory. It ultimately intends to show the extent to which Aquinas's conception of virtue depends upon a theological and specifically Christological understanding of human perfection. (shrink)

Achilles and Socrates: ancient attempts to integrate virtue, death, and human perfection -- Practical reason, perfection, and finitude in Aquinas -- Death and human perfection in Aquinas -- The role of courage in Aquinas's account of human perfection -- Aquinas on courage, martyrdom, and the common good -- Contemporary exemplarist virtue theory and moral motivation in the face of death -- The prospect and limitations of Thomistic moral exemplarism.

This paper draws upon the meta-ethical insights of Bernard Lonergan and Raimond Gaita to bolster the foundational claims of Linda Zagzebski’s exemplarist moral theory. I aim to refine Zagzebski’s approach by pointing out how a community’s inevitable prioritization of a given paradigm of moral exemplarity plays a decisive role in the trajectory of its ethical reasoning. I conclude by arguing that within the Christian community, encounters with sanctity should determine the identification of virtues rather than vice versa.