Effects of agreement and disagreement in groups on recognition memory performance and confidence

Three dependent variables, derived from an extended Signal-Detection paradigma, were used in each of 3 experiments: memory performance, confidence-level, and response-bias. Each memory item was first judged by S and then fictitiously by 2 confederates providing different degrees of agreement and disagreement. As compared to agreement moderate disagreement yielded both better recognition performance and, if S's judgements were false, less confidence. Strong disagreement failed to repeat these findings. Balanced agreement/disagreement raised the level of both performance and confidence relative to a situation without information from the group. In all the experiments correct decisions yielded higher confidence than errors. Festinger's theory of social comparison processes accounts for all results in performance, but for explaining the confidence shifts assumptions on ‘internal cues’ should also be incorporated. The response-bias was not affected by social treatment differences, thus supporting the view of some Signal-Detection theorists. Proposals towards a general theory of stimulus processing in social context are outlined and some of its consequences are discussed by taking as examples some conformity experiments.     

Nondirected light signals and the structure of time

Temporal betweenness in space-time is defined solely in terms of light signals, using a signalling relation that does not distinguish between the sender and the receiver of a light signal. Special relativity and general relativity are considered separately, because the latter can be treated only locally. We conclude that the (local) coherence of time can be described if we know only which pairs of space-time points are light-connected. Other consequences in the case of special relativity: (1) a categorical axiom system exists in terms of nondirected light connection alone, with neither particle nor time order as a primitive concept, though we do not actually present the axioms; (2) any concept definable by coordinates is also definable in terms of nondirected light signals if and only if it is invariant under Lorentz transformations, translations, dilations, space reflections, and time reflections; and (3) any transformation of space-time (not necessarily continuous) which preserves nondirected light connection is a product of transformations just listed above. The bulk of the paper is devoted to proving that the definitions we give correspond to their intended interpretations in the usual space-time continua.     

The asymptotic distribution of response probabilities in the Audley-Jonckheere learning model

The asymptotic distributions of response probabilities in the Audley-Jonckheere learning model, as applied to the two-choice learning situation, are described for (1) the experimenter-controlled events model, (2) the subject-controlled events model, and (3) the experimenter-subject-controlled events model.     

Detection of extraneous signals during sentence recognition

In two separate experiments, 40 Ss were presented with recorded sentences during each of which a click occurred. Ss had to depress a key as soon as they heard the click. RTs were f aster when the click was located at the major syntactic break of the sentence compared with RTs to clicks not at a break. This confirmed the hypothesis that processing load is a function of the surface structure of sentences, although the role of minor breaks was not clear. A second finding was that RTs were slower when the click was in the first rather than in the second half of the sentence. This can also be explained in terms of differential processing loads.