Biomedical subjects

Walter Schroyens

Publications and source records attributed to Walter Schroyens.

3 recordsLinked to original sources

PubMed2003

A critique of Oaksford, Chater, and Larkin's (2000) conditional probability model of conditional reasoning.

M. Oaksford, N. Chater, and J. Larkin (2000) proffered a Bayesian model in which conditional inferences are a direct function of conditional probabilities. In the current article, the authors first considered this model regarding the processing of negatives in conditional reasoning. Its predictions were evaluated against a large-scale meta-analysis (W. J. Schroyens, W. Schaeken, & G. d'Ydewalle, 2001b). This evaluation shows that the model is flawed: The relative size of the negative effects does not match predictions. Next, the authors evaluated the model in relation to inferences about affirmative conditionals, again considering the results of a meta-analysis (W. J. Schroyens, W. Schaeken, & G. d'Ydewalle, 2001a). The conditional probability model is countered by the data reported in literature; a mental models based model produces a better fit. The authors conclude that a purely probabilistic model is deficient and incomplete and cannot do without algorithmic processing assumptions if it is to advance toward a descriptively adequate psychological theory.

Conditioning, Psychological↗

PubMed2003

In search of counter-examples: deductive rationality in human reasoning.

Dual-process theories come in many forms. They draw on the distinction between associative, heuristic, tacit, intuitive, or implicit processes (System 1) and rule-based, analytic, explicit processes (System 2). We present the results of contextual manipulations that have a bearing on the supposed primacy of System 1 (Stanovich & West, 2000). Experiment 1 showed that people who evaluated logically valid or invalid conditional inferences under a timing constraint (N=56), showed a smaller effect of logical validity than did people who were not placed under a timing constraint (N= 44). Experiment 2 similarly showed that stressing the logical constraint that only inferences that follow necessarily are to be endorsed (N = 36) increased the size of the validity effect, as compared to that of participants (N=33) given the standard instruction to make "logical" inferences. These findings concur with the thesis in dual-processing frameworks that "Rationality-2 processes" (Evans & Over, 1996), "test procedures" (Chater & Oaksford, 1999), or "conclusion validation processes" (Johnson-Laird & Byrne, 1991; Schroyens, Schaeken, & d'Ydewalle, 2001) serve to override the results of System 1 processes.

Adolescent↗

PubMed2000

Heuristic and analytic processes in propositional reasoning with negatives.

The authors report 4 studies on heuristic and analytic processes in conditional reasoning with negations and show that a heuristic negative conclusion bias cannot account for the effects observed on problem-solving latencies derived from eye-movement measures (Experiment 1) and a novel mouse-tracking methodology (Experiment 2). A double negation elimination process can account for both the latency and response-frequency effects of a negation in the clause about which an inference is made. It is further shown that other negation effects cannot be explained by an affirmative premise bias proposed in the literature. Experiments 3 and 4 demonstrate that a novel availability hypothesis provides a viable alternative. It is argued that extant analytic theories need to be extended to incorporate a validating search for counter examples and need to specify how pragmatic and comprehension processes influence such a search.

Adult↗