1,720,998 research outputs found

    Effetti delle istruzioni sperimentali e della probabilità in un compito di inferenza con enunciati di forma se p allora non-q

    Full text link
    According to psychological theories dealing with propositional logic, conditional reasoning is a form of deductive reasoning. On the contrary, theories referring to Ramsey's suppositional interpretation posit that conditional statement (if p then q) is equivalent to the conditional probability of the consequent (q) given the antecedent (p) and that conditional reasoning is a form of probabilistic reasoning. This study compared the two competing hypotheses through an inference task where conditional syllogisms were presented with both premises (major premise «if p then not-q» and minor premises p, not-p not-q, q) or with minor premise only, and the conditional probability of «if p then not-q», the antecedent size and the consequent size were separately varied. In relation to Modus Ponens, results showed that, with the complete conditional syllogism, neither the conditional probability of «if p then not-q» nor the p and not-q size affected this inference. The theoretical implications are discussed in the text

    Probability and instruction effects in syllogistic conditional reasoning

    No full text
    The main aim of this study was to examine whether people understand indicative conditionals on the basis of syntactic factors or on the basis of subjective conditional probability. The second aim was to investigate whether the conditional probability of q given p depends on the antecedent and consequent sizes or derives from inductive processes leading to establish a link of plausible co-occurrence between events semantically or experientially associated. These competing hypotheses have been tested through a 3 x 2 x 2 x 2 mixed design involving the manipulation of four variables: type of instructions (“Consider the following statement to be true”, “Read the following statement” and condition with no conditional statement); antecedent size (high/low); consequent size (high/low); statement probability (high/low). The first variable was between-subjects, the others were within-subjects. The inferences investigated were Modus Ponens and Modus Tollens. Ninety undergraduates of the Second University of Naples, without any prior knowledge of logic or conditional reasoning, participated in this study. Results suggest that people understand conditionals in a syntactic way rather than in a probabilistic way, even though the perception of the conditional probability of q given p is at least partially involved in the conditionals’ comprehension. They also showed that, in presence of a conditional syllogism, inferences are not affected by the antecedent or consequent sizes. From a theoretical point of view these findings suggest that it would be inappropriate to abandon the idea that conditionals are naturally understood in a syntactic way for the idea that they are understood in a probabilistic way

    Compiti di inferenza con condizionali, congiunzioni e disgiunzioni incompatibili: processi di ragionamento deduttivi o probabilistici?

    No full text
    Nel presente studio sono state messe a confronto le ipotesi contrastanti derivanti dalle teorie deduttive, dagli approcci probabilistici e dalle teorie duali del ragionamento, mediante un compito inferenziale con enunciati condizionali (Se A, allora B), congiuntivi (A e B) e disgiuntivi incompatibili (o A o B). Il disegno sperimentale prevede la manipolazione di tre variabili within subjects: enunciato (condizionale/congiuntivo/disgiuntivo), livello di probabilità dell’enunciato (alto/basso) e istruzioni sperimentali (deduttiva/pragmatica). I risultati hanno messo in luce che, in linea con le previsioni degli approcci dualistici, il ragionamento umano è sensibile agli effetti della probabilità delle conclusioni ma che tale tendenza diminuisce in presenza di istruzioni deduttive che richiedono di concentrarsi sulla forma logica degli argomenti

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
    corecore