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G Haubensak

Publications and source records attributed to G Haubensak.

7 recordsLinked to original sources
PubMed2001

Higher order sequential effects in psychophysical judgments.

We found that the depth of sequential effects depends on the judgment task. An experiment with squares indicated that stimulus-response pairs up to two trials back were included in the judgment process when subjects were required to make category judgments of size, whereas only the immediately preceding event was incorporated when subjects were making magnitude estimations. In the case of category judgment, interactions between the current stimulus and prior stimuli as well as configural effects indicated that events one and two trials back meet an equivalent function in the judgment process and that these events may jointly operate in one trial. These findings can be explained by a class of models that assume that the position of preceding stimuli relative to the current stimulus is decisive in the judgment process. The multiple-standards model is a representative of this class according to which there are two types of standards: (1) the endpoints of the range as long-term standards and (2) traces of preceding stimuli as short-term standards.

Adult↗
PubMed1994

[What is the origin of the frequency effect in absolute judgment? A contribution to the theory of judgment].

The same stimuli receive higher ratings when the distribution in which they appear is positively skewed than when it is negatively skewed (frequency effect). The effect depends on the number of stimuli (stimulus effect) and the number of categories (category effect). The effect may be caused by one of the following tendencies: (a) the tendency to assign the same number of stimuli to each category (frequency model; Parducci, 1965; Parducci & Perrett, 1972); (b) the tendency to exaggerate the difference between the preceding stimulus and the present one (contrast model; Haubensak, 1984); and (c) the tendency to assign the same categories to the same stimuli (consistency model; Haubensak 1989, 1992a, 1992b, 1993). The three models are briefly described and evaluated in the light of old and new data. The consistency model seems superior to its competitors in several respects.

Attention↗
PubMed1992

[Sequence effects in absolute judgment? Critical comments on the method].

Several methods for demonstrating sequential effects in psychophysical judgments are discussed. None of them is free of problems. Simple simulations show that pseudosequential effects occur whenever some subjects judge the stimuli higher or lower than they should. Such effects may also be produced by response drifts during the course of an experiment. Breaks in the psychophysical function might be another source of pseudosequential effects. Contrary to a wide-spread opinion, it still remains to be shown that genuine sequence effects really exist.

Arousal↗
PubMed1989

[Primacy effects in psychophysical judgements].

In the first of a series of three experiments, two groups of 10 subjects judged either the bottom half or the top half of a series of 16 squares according to their size. After two presentations with the pretraining series, 10 trials with the total series followed. The initial judgments of the pretraining stimuli showed a marked tendency to persist all through the experiment, thus demonstrating a primacy effect. The effect was not completely removed by instructions to modify the judgment scale (Experiment 2). In the third experiment, the number of categories was varied. With a larger number of categories the primacy effect tended to wear off after a few postshift trials. The results are interpreted as providing an alternative explanation of the frequency effect and the number-of-categories effect discovered by Parducci. The present paper considers the frequency effect a special case of the primacy effect. The explanation is based on the fact that ordinarily stimulus frequency and time of first occurrence are confounded.

Adult↗