Simplicity and probability in causal explanation

What makes some explanations better than others? This paper explores the roles of simplicity and probability in evaluating competing causal explanations. Four experiments investigate the hypothesis that simpler explanations are judged both better and more likely to be true. In all experiments, simplicity is quantified as the number of causes invoked in an explanation, with fewer causes corresponding to a simpler explanation. Experiment 1 confirms that all else being equal, both simpler and more probable explanations are preferred. Experiments 2 and 3 examine how explanations are evaluated when simplicity and probability compete. The data suggest that simpler explanations are assigned a higher prior probability, with the consequence that disproportionate probabilistic evidence is required before a complex explanation will be favored over a simpler alternative. Moreover, committing to a simple but unlikely explanation can lead to systematic overestimation of the prevalence of the cause invoked in the simple explanation. Finally, Experiment 4 finds that the preference for simpler explanations can be overcome when probability information unambiguously supports a complex explanation over a simpler alternative. Collectively, these findings suggest that simplicity is used as a basis for evaluating explanations and for assigning prior probabilities when unambiguous probability information is absent. More broadly, evaluating explanations may operate as a mechanism for generating estimates of subjective probability.     

Mental Health Clinicians' Beliefs About the Biological, Psychological, and Environmental Bases of Mental Disorders

The current experiments examine mental health clinicians' beliefs about biological, psychological, and environmental bases of the DSM-IV-TR mental disorders and the consequences of those causal beliefs for judging treatment effectiveness. Study 1 found a large negative correlation between clinicians' beliefs about biological bases and environmental/psychological bases, suggesting that clinicians conceptualize mental disorders along a single continuum spanning from highly biological disorders (e.g., autistic disorder) to highly nonbiological disorders (e.g., adjustment disorders). Study 2 replicated this finding by having clinicians list what they thought were the specific causes of nine familiar mental disorders and rate their bio–psycho–environmental bases. Study 3 further found that clinicians believe medication to be more effective for biologically based mental disorders and psychotherapy to be more effective for psychosocially based mental disorders. These results demonstrate that even expert mental health clinicians make strong distinctions between psychological and biological phenomena.     

Back to the future: Temporal perspective in the explanation of events

Prospective hindsight involves generating an explanation for a future event as if it had already happened; i.e., one goes forward in time, and then looks back. In order to examine how shifts in perspective might influence people's perceptions of events, we investigated two possible factors: temporal perspective (whether an event is set in the future or past) and uncertainty (whether the event's occurrence is certain or uncertain). In the first experiment, temporal perspective showed little influence while outcome uncertainty strongly affected the nature of explanations for events. Explanations for sure events tended to be longer, to contain a higher proportion of episodic reasons, and to be expressed in past tense. Evidence from the second experiment supports the view that uncertainty mediates not the amount of time spent explaining, but rather subjects' choice of explanation type. The implications of these findings for the use of temporal perspective in decision aiding are discussed.     

Explanation and categorization: How “why?” informs “what?”

Recent theoretical and empirical work suggests that explanation and categorization are intimately related. This paper explores the hypothesis that explanations can help structure conceptual representations, and thereby influence the relative importance of features in categorization decisions. In particular, features may be differentially important depending on the role they play in explaining other features or aspects of category membership. Two experiments manipulate whether a feature is explained mechanistically, by appeal to proximate causes, or functionally, by appeal to a function or goal. Explanation type has a significant impact on the relative importance of features in subsequent categorization judgments, with functional explanations reversing previously documented effects of ‘causal status’. The findings suggest that a feature’s explanatory importance can impact categorization, and that explanatory relationships, in addition to causal relationships, are critical to understanding conceptual representation.     

Young children's selective learning of rule games from reliable and unreliable models

We investigated preschoolers’ selective learning from models that had previously appeared to be reliable or unreliable. Replicating previous research, children from 4 years selectively learned novel words from reliable over unreliable speakers. Extending previous research, children also selectively learned other kinds of acts – novel games – from reliable actors. More important, – and novel to this study, this selective learning was not just based on a preference for one model or one kind of act, but had a normative dimension to it. Children understood the way a reliable actor demonstrated an act not only as the better one, but as the normatively appropriate or correct one, as indicated in both their explicit verbal comments and their spontaneous normative interventions (e.g., protest, critique) in response to third-party acts deviating from the one demonstrated. These findings are discussed in the broader context of the development of children's social cognition and cultural learning.     

Children's understanding of belief as a normative concept

The variety of accounts of theory of mind development, arising from distinct theoretical perspectives, have focused on children's causal-explanatory views on the mind and have not developed accounts of children's normative judgments of the mental domain. This review maintains that such a focus is unfortunate and leaves our understanding of belief as a concept incomplete. First, by presenting an alternative framework that treats belief as a normative concept, this account discusses the central importance of children's understanding of epistemic justification and their appreciation of the normative significance of others’ reasons for belief. Next, this review of the relevant theory of mind literature proposes a new way of thinking about the findings of various domains in this field and gives particular attention to prior work on false belief, origins or sources of belief, and the distinctions between fantastical and epistemic states. On the basis of this review, it is concluded that in order to accurately assess the development of the concept of belief, further research is required on children's views of how beliefs ought to be formed, their evaluation of justified and unjustified believers, and the notions of duty or responsibility they associate with epistemic agents.     

Summarizing information by means of causal sentences through causal graphs

The objective of this work is to propose a complete system able to extract causal sentences from a set of text documents, select the causal sentences contained, create a causal graph in base to a given concept using as source these causal sentences, and finally produce a text summary gathering all the information connected by means of this causal graph. This procedure has three main steps. The first one is focused in the extraction, filtering and selection of those causal sentences that could have relevant information for the system. The second one is focused on the composition of a suitable causal graph, removing redundant information and solving ambiguity problems. The third step is a procedure able to read the causal graph to compose a suitable answer to a proposed causal question by summarizing the information contained in it.     

A Schutzian Perspective on the Phenomenology of Law in the Context of Positivistic Practices

The paper outlines Schutz’s phenomenology of law in the context of the transformation of positivistic practices in a post-totalitarian society. His major contribution is seen in the disentanglement of social phenomena from any form of naturalness by incorporating the dimension of meaning and interpretation into them. This philosophical gesture is made possible by renouncing any theory of transcendent ground(s) of a pre-formed order (Section 1) and leads to an interpretive concept of law, in which the reciprocity of perspectives play the major role. The conclusions are pointing toward a phenomenological concept of law able to take our freedom seriously. Presented as the Alfred Schutz Memorial Lecture at the meetings of the Society for Phenomenology and the Human Sciences (SPHS), Chicago, 2007, and co-sponsored by the American Philosophical Association (APA) and the Center for Advanced Research in Phenomenology (CARP). I am grateful to Lester Embree and Nicoleta Szabo for their comments on an earlier draft of this essay.     

Normativity and context in young children's pretend play

In two studies 3-year-olds’ understanding of the context-specificity of normative rules was investigated through games of pretend play. In the first study, children protested against a character who joined a pretend game but treated the target object according to its real function. However, they did not protest when she performed the same action without having first joined the game. In the second study, children protested when the character mixed up an object's pretend identities between two different pretend games. However, they did not protest when she performed the same pretend action in its correct game context. Thus, the studies show that young children see the pretence–reality distinction, and the distinction between different pretence identities, as normative. More generally, the results of these studies demonstrate young children's ability to enforce normative rules in their pretence and to do so context-specifically.     

Attention focusing instructions and coordination bias: Implications for learning a novel bimanual task

Four groups learnt a novel bimanual coordination movement pattern under instructions designed to manipulate focus of attention. It was predicted that instructions directing attention onto the effects of the action would facilitate learning. Three groups received demonstrations of the required 90° relative phase movement. Two of the demonstration groups also received instruction directing attention either towards the feedback (EXTERNAL), or the relationship between their arm movements and the feedback (RELATION). The third group received no attention directing instructions (DEMO). A final group was only provided with goal relevant feedback (NO DEMO). A scanning task enabled coordination bias to be assessed pre-practice. This was conducted to ensure task novelty and assign participants equally across groups based on strength of bias to in- and/or anti-phase. Acquisition rate was slower for the DEMO only group, especially compared to the EXTERNAL group. Additionally, participants biased to in-phase (as compared to anti-phase) during the scanning trial also showed high error early in practice. These differences remained in retention. Irrespective of feedback condition the DEMO group evidenced the most error in retention. However, all groups were affected by the removal of on-line feedback, although the attention-directing instructions provided during practice somewhat decreased the negative effects associated with feedback removal. Overall, the in-phase-biased participants were most affected by withdrawal of feedback. It was concluded that movement demonstrations alone do not facilitate learning of a novel coordination task, unless additional goal-directed instruction is provided. Additionally, individual differences in coordination bias pre-practice can be used to predict learning rate and quality.