Response frequency equalization: A bias model for psychophysics

A model for response bias in psychophysics is derived. Of the model’s two aspects, one is concerned with the generation of sensory states and the other with rules for transforming sensory states into responses. The model incorporates the bias rule that Ss tend to use available responses with equal frequency. Applications to experiments which use the method of constant stimuli are discussed. Despite the contrary claims of Restle and Levison (1971), the model not only predicts their data quite well but also, under certain conditions, does so better than the theory of adaptation level used by Restle and Levison themselves.     

Response bias in deaf and hearing subjects as a function of motivational factors

This experiment assessed the effect of different payoff matrices on 6 deaf and 6 hearing subjects on a visual brightness discrimination task. Subjects were required to make forced-choice responses to three different monetary payoff conditions, designed to induce a liberal, a conservative, and an equal-bias response criterion, respectively. The results showed that the deaf did not select the superior response strategies they had exhibited in a previous study (Bross, 1979) on the effect of changes in stimulus probability. Furthermore, the deaf earned significantly less money than the controls for all three conditions, indicating that the introduction of motivational demands affects their response strategies adversely.     

Response bias and the discrimination of stimulus duration

Pigeons discriminated stimulus duration in a psychophysical choice situation. Following presentation of any duration from a set of short duration (11 to 15 sec), responses on a red key were reinforced intermittently. Following presentation of any duration from a set of long durations (16 to 22 sec), responses on a green key were reinforced intermittently. Relative reinforcement rates were manipulated for choice responses across conditions. As relative reinforcement rates were varied, psychometric functions showed shifts in green-key responses at all durations. A signal-detection analysis showed that sensitivity remained roughly constant across conditions while response bias changed as a function of changes in relative reinforcement rate. Relative error rates tended to match relative reinforcement rates.     

Response bias and the measurement of choice alternation

The problem of devising a measure of alternation of choices that is independent of response bias is considered. Previous solutions are equivalent to the correction for chance guessing in the Yes/No experiment of psychophysics, and require an estimate of response bias, usually from choices on the first of two daily trials. This involves the questionable assumption that response bias is homogeneous over time or across subjects. It is suggested that spontaneous alternation is analogous to the two alternative forced choice situation of psychophysics, and the fourfold point correlation is proposed as an index of alternation that is statistically independent of response bias. Implications for interpreting the effect upon spontaneous alternation of hippocampal and other lesions are considered.     

Dissociation of sensory facilitation and decision bias in statistical learning

ABSTRACT

The detection of regularities in the sensory environment, known as statistical learning, is an important brain function that has been observed in many experimental contexts. In these experiments, statistical learning of patterned sensory stimulation leads to improvements in the speed and/or accuracy with which subsequent stimuli are recognized. That is, statistical learning facilitates the transformation of sensory stimuli into motor responses, but the mechanism by which this occurs is unclear. Statistical learning could improve the efficiency of sensory processing, or it could bias responses toward particular outcomes. The distinction is important, as these different hypotheses imply different functions and different neural substrates for statistical learning. Here we address this problem by studying statistical learning as a decision-making process, which allows us to leverage the extensive computational literature on this topic. Specifically we describe a method for applying the Diffusion Decision Model (DDM) to isolate different sensory and cognitive processes associated with decision-making. The results indicate that statistical learning improves performance on a visual learning task in two distinct ways: by altering the efficiency of sensory processing and by introducing biases in the decision-making process. By fitting the parameters of the DDM to data from individual subjects, we find that the prominence of these two factors differed substantially across the population, and that these differences were predictive of individual performance on the psychophysical task. Overall, these results indicate that different cognitive processes can be recruited by statistical learning, and that the DDM is a powerful framework for detecting these influences.     

Response bias,social desirability and dissimulation

This review set out to review the extensive literature on response bias, and particularly dissimulating a socially desirable response to self-report data. Various terminological differences are discussed as well as the way test constructors attempt to measure or overcome social desirability response sets. As an example of the research in this field, four types of studies measuring social desirability in the Eysenckian personality measures (MPI, EPI, EPQ) are reviewed. Also studies of faking in psychiatric symptom inventories, and a wide range of other tests are briefly reviewed. Various equivocal results from attempts to determine what makes some measures more prone to social desirability than others. However there appears to be growing evidence that social desirability is a relatively stable, multidimensional trait, rather than a situationally-specific response set. Faking studies may also be used to examine people's stereotypes and images of normality and abnormality, and various studies of‘abnormal groups’ perception of normality are examined. Recommendations for further work in this area are proposed.     

Response bias in judging deceptive movements

Two not mutually exclusive explanations, perceptual and motor expertise, account for the finding that experts outperform novices in recognizing deceptive actions from bodily (kinematic) cues. The aim of the present study was twofold: First, we sought to examine the impact of motor and perceptual expertise on distinguishing deceptive and non-deceptive actions. Second, we tested the hypothesis that differences in perceptual judgments on deceptive movements vs. non-deceptive movements do not necessarily need to be caused by either perceptual or motor expertise differences, but can also be a result of response bias. Skilled handball players (field players and goalkeepers) and novices had to detect whether a penalty-taker shot or faked a shot at the goal. Signal detection theory (SDT) analysis revealed that skilled handball players outperformed novices in discriminating shots from fakes. No differences in perceptual sensitivity were found between the goalkeepers and the field players. However, SDT analysis showed that goalkeepers were significantly biased to judge movements as deceptive, while neither field players nor novices showed this response bias.     

Response bias in sex-role attitude measurement

The widespread use of survey research by social scientists as a means for generating data has prompted an examination of the interview situation for sources of bias. Two potential aspects of the interview have been of particular interest to analysts — dissimilarities between interviewers and subjects on key sociopersonal variables and the nature of the subject matter of the interview. This study examines the impact of sex differences between interviewers and subjects on responses to a sensitive subject-matter area — sex-role orientations — in a telephone interview situation.The authors wish to acknowledge the assistance of members of an introductory research methods class at LSU during spring 1980 for their help in gathering the data upon which this article is based.     

Response bias and judgments of the location of clicks in sentences

This study examines the view that response bias is the basis of the “click effect,” i.e., the influence of grammatical structure on subjects’ location of clicks sounded during the presentation of a sentence. It is argued that, since response bias is more likely to operate when one is unsure of one’s perception, if response bias generates the “click effect,” the effect should be weaker for certain than for uncertain responses. Subjects were asked to identify the location of the click and allowed to make more than one response if they were uncertain of their first choice. Using the number of locations selected as an index of uncertainty, it was found that when a subject was less certain, the click was less likely to be judged as having occurred in the major grammatical break. Further, performance was superior when the click had been in the break, and this effect, which was more pronounced for “certain” responses, was not eliminated by correcting for possible response bias. It is concluded that the "click effect" is not attributable solely to response bias.     

Response bias and hemispheric differences in dot localization

A series of studies investigated the accuracy of dot localization in left and right visual fields. The left visual field superiority previously reported for this task was found to be small and statistically inconsistent. It was unaffected by the presence of a frame of reference, the location of the response card, or the sex of the subject. It was observed, however, that the majority of subjects showed a response bias favoring the report of items in the left visual field. This suggests that the right hemisphere is less critical than the left in its assessment of incoming information, and may provide a basis for understanding previous reports of right hemispheric superiority on dot localization. It is concluded that dot localization does not provide a reliable measure of right hemisphere performance.     

Response restriction and substitution with autistic children.

Few studies to date have examined time reallocation in naturalistic, multiresponse human repertoires when one or more responses are restricted. For this experiment, free-operant baseline levels of six responses were measured for four autistic children. The high-probability responses were made unavailable, one at a time, such that subjects had access to five, four, three, and two responses in successive restriction conditions. A return to the six-response free-operant baseline condition completed the experiment. Results were compared to predictions made by four time-reallocation models. These results were described accurately only by the selective substitution model. Further analyses examined alternative explanations for the individual reallocation patterns obtained. An expanded selective substitution definition is proposed that may characterize orderly patterns observed in multiresponse repertoires under restriction conditions more accurately than the other existing models.     

The truth and bias model of judgment

We present a new model for the general study of how the truth and biases affect human judgment. In the truth and bias model, judgments about the world are pulled by 2 primary forces, the truth force and the bias force, and these 2 forces are interrelated. The truth and bias model differentiates force and value, where the force is the strength of the attraction and the value is the location toward which the judgment is attracted. The model also makes a formal theoretical distinction between bias and moderator variables. Two major classes of biases are discussed: biases that are measured with variables (e.g., assumed similarity) and directional bias, which refers to the extent to which judgments are pulled toward 1 end of the judgment continuum. Moderator variables are conceptualized as variables that affect the accuracy and bias forces but that do not affect judgments directly. We illustrate the model with 4 examples. We discuss the theoretical, empirical, methodological, measurement, and design implications of the model.