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G Haubensak

Publications and source records attributed to G Haubensak.

5 recordsLinked to original sources
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↗