Interactive Constrained Association Rule Mining

We investigate ways to support interactive mining sessions, in the setting of association rule mining. In such sessions, users specify conditions (queries) on the associations to be generated. Our approach is a combination of the integration of querying conditions inside the mining phase, and the incremental querying of already generated associations. We present several concrete algorithms and compare their performance.Comment: A preliminary report on this work was presented at the Second International Conference on Knowledge Discovery and Data Mining (DaWaK 2000

Is conflict adaptation triggered by feature repetitions? An unexpected finding

For decades, cognitive adaptation to response conflict has been considered to be the hallmark of cognitive control. Notwithstanding a vast amount of evidence ruling out low-level interpretations of these findings, disbelief still exists with regard to the underlying cause of the observed effects. Especially when considering cognitive adaptation to unconscious conflict, it is still a matter of debate whether repetitions of features between trials might explain this intriguing finding rather than the involvement of unconscious control. To this purpose, we conducted two masked priming experiments in which four different responses to four different stimuli were required. This allowed us to completely eliminate repetitions of prime and target over consecutive trials. Independent of whether conflicting information was presented clearly visible or almost imperceptible, the results showed an unexpected pattern. Contrary to the regular congruency sequence effect (CSE; i.e., classic Gratton effect), in both experiments the congruency effect increased following incongruent trials. Interestingly, this reversed effect completely disappeared when we eliminated all trials with feature repetitions from the analysis. A third experiment, in which feature repetitions were excluded a priori, showed a small but regular CSE in the error rates only. Given that feature repetitions are theoretically thought to create a regular CSE, our results are not in line with an interpretation in terms of feature repetitions nor with an interpretation in terms of cognitive control. We conclude that examining cognitive adaptation with or without feature repetitions might be more difficult to conceive than is often suggested in the literature

Beyond trial-by-trial adaptation : a quantification of the time scale of cognitive control

The idea that adaptation to stimulus or response conflict can operate over different time scales takes a prominent position in various theories and models of cognitive control. The mechanisms underlying temporal variations in control are nevertheless poorly understood, which is partly due to a lack of appropriate empirical measures. Inspired by reinforcement learning models, we developed a method to quantify the time scale of control behaviorally, by computing trial-by-trial effects that go beyond the preceding trial. Briefly, we extended the congruency sequence effect from 1 trial to multiple trials into the past and quantified the influence of previous trials on current-trial performance as a function of trial distance. The rate at which this influence changes across trials was taken as a measure of the time scale of control. We applied the method to a flanker task with different conflict frequencies and volatility. Results showed that the time scale of control was smaller in rare-conflict and volatile contexts, compared to frequent-conflict and neutral contexts. This is in agreement with theories differentiating transient from sustained control. The method offers new opportunities to reveal temporal differences in control modes and can easily be applied to various empirical paradigms. (PsycINFO Database Recordstatus: publishe

Is conflict adaptation an illusion?

Conflict adaptation theory is one of the most popular theories in cognitive psychology. The theory argues that participants strategically modulate attention away from distracting stimulus features in response to conflict. Although results with proportion congruent, sequential congruency, and similar paradigms seem consistent with the conflict adaptation view, some researchers have expressed scepticism. The paradigms used in the study of conflict adaptation require the manipulation of stimulus frequencies, sequential dependencies, time-on-task regularities, and various other task regularities that introduce the potential for learning of conflict-unrelated information. This results in the unintentional confounding of measures of conflict adaptation with simpler learning and memory biases. There are also alternative accounts which propose that attentional adaptation does occur, but via different mechanisms, such as valence, expectancy, or effort. A significant (and often heated) debate remains surrounding the question of whether conflict adaptation exists independent of these alternative mechanisms of action. The aim of this Research Topic is to provide a forum for current directions in this area, considering perspectives from all sides of the debate