The influence of different instructions on the effects of stimulus membership in category ratings. Primary data.

Cognitive Psychology

Authors(s) / Creator(s)

Petzold, Peter
Haubensak, Gert

Abstract

According to the model of multiple standards, the boundaries of the stimulus area and the memory representations of previous stimuli have an equivalent function in the decision process: They serve as internal standards by which the depicted stimulus is compared. If this assumption is correct, then the influence of stimulus area and the influence of preceding stimuli follow the same regularities.
This hypothesis was examined for the effect of instruction on the modification of judgments via stimulant classification. Subjects assessed the size of squares on a 5-point rating scale. There were two classes of squares: empty or shaded. In Experiment 3, the subjects were asked to judge the empty squares only in relation to the other empty squares and the shaded squares only in relation to the other shaded squares (separation instruction). In Experiment 4, subjects were instructed to ignore the stimulus classes and to assess the individual squares in terms of all the squares (integration instructions). The discrepancies between the results of Experiments 3 and 4 confirmed the predictions of the model. In Experiment 3, the increase in the psychophysical function demonstrated that the class-specific area of the squares had been used. However, in Experiment 4, the entire stimuli area was decisive for assessing the size of the squares. For example, in Experiment 3 the sequence effect was stronger when the preceding stimulus belonged to the same class as the following stimulus, while in Experiment 4 the strength of the sequence effect was independent of any similarities between the presented stimuli. This confirms the equivalent effect of procedural structure on area effects and sequence effects.
The effect of stimulus classification on sequence effects was studied in more detail in Experiment 3. Interactions between the stimulus-judgment events were found in one and two trials prior to the actual trial. When both the preceding stimuli belong to the same class as the presented stimulus, the correlation between successive judgments is lower than when only the immediately preceding stimulus (but not the stimulus two trials prior) belongs to the same class as the presented stimulus.

Persistent Identifier

https://doi.org/10.5160/psychdata.pdpr99ei20

Year of Publication

2004

Funding

German Research Foundation

Citation

Petzold, P. & Haubensak, G. (2004). The influence of different instructions on the effects of stimulus membership in category ratings. Primary data. (Version 1.0.0) [Data and Documentation]. Trier: Research Data Center at ZPID. https://doi.org/10.5160/psychdata.pdpr99ei20

Study Description

Research Questions/Hypotheses:

Null hypotheses:

The instruction affects only the class specificity from the influence of the stimulus range.
With regard to the sequential dependencies, there is no interaction between the specified class of the stimuli 1 and 2 trials back.

Alternative hypotheses:

The instruction influences both the class specificity of area effects and sequential dependencies in the same way.
The effects of sequence immediately preceding stimuli and judgments are lower when both the stimulus from 1 trial back as well as the stimulus from 2 trials back belong to the same class as compared to when only the proffered stimulus from 1 trial back belongs to the same class.

Research Design:

Experimental Design, Mixed Design, Laboratory Experiment; single measurements

Measurement Instruments/Apparatus:

Stimuli consisted of 16 squares belonging to 2 classes: empty and shaded squares. The lengths of the squares in the 2 classes were chosen so that 1) a class of small and a class of larger squares were formed and 2) an overlap occurred in the classes, so that there were squares with the same length in both classes (4 squares of the edge lengths of 62-71mm).
12 students took part, having no previous experience with this kind of experiment. These subjects were divided and randomly given either the “separation” instructions (Experiment 3) or the “integration” instructions (Experiment 4). The wording of the instructions is found in the experimental program. The subjects were asked to judge the size of the squares on a 5-point rating scale . They had to press the corresponding number key on the keyboard. The next square appeared 1 second after each response. No feedback was given. Sessions consisted of 3 parts, each lasting about 15 minutes with 5-minute breaks. Square were randomly presented. It was verified that the autocorrelation function of the stimuli up to 8 trials back adopted no significant value.

Data Collection Method:

Data collection in the presence of an experimenter

Individual administration
Computer-supported

Population:

Survey Time Period:

1998 to 1999

Sample:

Convenience sample

Gender Distribution:

58,3% female subjects (n=7)
41,7% male subjects (n=5)

Age Distribution: 20-26 years

Spatial Coverage (Country/Region/City): Germany

Subject Recruitment:

Sample Size:

12 individuals

Return/Drop Out:

pdpr99ei20_readme.txt

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