Multidimensional scaling models for reaction times and same-different judgments

A method for joint analysis of reaction times and same-different judgments is discussed. A set of stimuli is assumed to have some parametric representation which uniquely defines dissimilarities between the stimuli. Those dissimilarities are then related to the observed reaction times and same-different judgments through a model of psychological processes. Three representation models of dissimilarities are considered, the Minkowski power distance model, the linear model, and Tversky's feature matching model. Maximum likelihood estimation procedures are developed and implemented in the form of a FORTRAN program. An example is given to illustrate the kind of analyses that can be performed by the proposed method.The work reported in this paper is supported by Grant A6394 to the first author from the Natural Sciences and Engineering Research Council of Canada. Portions of this study have been presented at the Psychometric Society meeting in Chapel Hill, N.C., in May, 1981. We thank Tony Marley, Jim Ramsay and anonymous reviewers for their helpful comments. MAXRT, a computer program which performs the computations described in this paper may be obtained by writing to the first author.     

Dissociations between reaction times and temporal order judgments: a diffusion model approach

A diffusion model for simple reaction time (RT) and temporal order judgment (TOJ) tasks was developed to account for a commonly observed dissociation between these 2 tasks: Most stimulus manipulations (e.g., intensity) have larger effects in RT tasks than in TOJ tasks. The model assumes that a detection criterion determines the level of sensory evidence needed to conclude that a stimulus has been presented. Analysis of the performance that would be achieved with different possible criterion settings revealed that performance was optimal with a lower criterion setting for the TOJ task than for the RT task. In addition, the model predicts that effects of stimulus manipulations should increase with the size of the detection criterion. Thus, the model suggests that commonly observed dissociations between RT and TOJ tasks may simply be due to performance optimization in the face of conflicting task demands.     

Comparative judgments of symbolic and non-symbolic stimuli yield different patterns of reaction times

Are different magnitudes, such as Arabic numerals, length and area, processed by the same system? Answering this question can shed light on the building blocks of our mathematical abilities. A shared representation theory suggested that discriminability of all magnitudes complies with Weber's law. The current work examined this suggestion. We employed comparative judgment tasks to investigate different types of comparisons — conceptual comparison of numbers, physical comparison of numbers and physical comparison of different shapes. We used 8 different size ratios and plotted reaction time as a function of these ratios. Our findings suggest that the relationship between discriminability and size ratio is not always linear, as previously suggested; rather, it is modulated by the type of comparison and the type of stimuli. Hence, we suggest that the representation of magnitude is not as rigid as previously suggested; it changes as a function of task demands and familiarity with the compared stimuli.     

Humanness beliefs about behavior: An index and comparative human-nonhuman behavior judgments

Social psychological research suggests that two distinct dimensions describe lay conceptions of humanness: a species-typical sense (i.e., human nature) and a species-unique sense (i.e., human uniqueness). Although these two senses of humanness have been discerned among psychological traits and states, there has been no systematic research into lay beliefs about the humanness of human behaviors. Using a range of 60 prosocial, nonsocial, and antisocial behaviors, it was demonstrated that people discriminate between species-typical and species-unique behaviors and that the capacity to perform species-unique behaviors distinguishes humans from animals, whereas the capacity to perform species-typical behaviors distinguishes humans from robots. Behaviors that exemplify the two senses of humanness are identified, and data representing rankings, raw scores, and z-scores in two indices of species typicality and species uniqueness are provided. Taken together, these findings expand our understanding of lay conceptions of humanness and provide researchers of humanness with a wider range of validated stimuli to probe the boundaries of humanity.     

An auditory Stroop effect with judgments of speaker gender

A series of “auditory Stroop” experiments is described. These demonstrate an effect of stimulus words presented on speed of judgments of speaker gender and, conversely, an influence of speaker gender on judgments of words presented. In an experiment in which responses to speaker gender were semantically related to, but not identical with, stimulus words, the auditory Stroop effect was attenuated but remained in evidence. Potential parallels between this auditory paradigm and the visual Stroop color/word effect are explored, and it is suggested that the Stroop effects in the two modalities operate along broadly similar lines. The search for a common causal mechanism would therefore be justified.     

Judgments about judgments: the dissociation of consideration price and transaction commitment judgments

There are many contexts in which people make judgments about prior judgments. For example, Internet shopping bots (e.g., NexTag.com) allow consumers to search for products and, if the price is too high, list a price at which they would consider making the purchase (i.e., base judgment). If the price drops to this level, the vendor generates an e-mail inviting the consumer to execute the transaction at the reduced price (i.e., contingent judgment). The authors show that the consideration price depends on the content of retrieved information, whereas the willingness to execute the transaction at the consideration price depends on the ease-of-retrieving the information. The authors use different offer prices to encourage the consumer to retrieve information consistent with different product quality levels. The authors also select offer prices so that information retrieval is more difficult at moderate offer prices than at high or low offer prices. Accordingly, the authors show that the consideration price increases as the offer price increases, but the willingness to execute the transaction at the consideration price is greater when there are high and low, as opposed to moderate, offer prices.     

Choice reaction times for temporal numerosity

Subjects watched rapidly presented visual sequences of two events until they decided which event was the more frequent. Accuracy was reduced both by increased rates of presentation and by the addition of more inconclusive information to the initial portion of the sequence. Response latencies were longest when there was no objective numerosity inbalance, and they decreased, for both correct responses and errors, when discrimination was relatively easy. The patterns of decision latencies for individual subjects could be represented on a continuum defined by the sensitivity of the latencies to the rate of event presentation and to the objective inbalance between the two events. The discussion points out formal and empirical similarities between sequential numerosity judgments and choice reaction times. The present results are discussed within the framework of a first-passage time model, to be developed formally in a subsequent paper.     

Choice reaction times for skilled responses

Two kinds of choice reaction time experiments are reported, both of which make use of a highly overlearned sensori-motor response. When a response is required for each stimulus presented, no increase in reaction time occurs as a function of the number of alternative stimuli available. It is proposed that the increase in choice reaction times commonly thought to accompany an increase in the number of alternative choices provided reflects the unpractised state of the responder. When a response is required for only one out of n possible stimuli, a slight but consistent increase in reaction time takes place with an increase in the number of alternatives. An analogy is drawn between the second experiment and a vigilance task and an expectancy hypothesis is invoked to explain the results.     

An analysis of individual differences in similarity judgments about complex random forms

A variation of the method of graded dichotomies was used to obtain judgments of interstimulus similarity for all pairings of 21 12-turn random shapes. Using the Tucker-Messick procedure, a six-dimensional spatial model, representing individual variation in performance on the task, was derived. Six “idealized individuals” (IIs) were isolated. A five-dimensional Euclidean spatial model was obtained for each II using the Shepard-Kruskal scaling technique. The resulting psychological dimensions of perceived form were related to two sets of physical measures on the forms: the factor space suggested by Brown and Owen and a set of more basic physical measures. These basic measures allowed interpretation of most of the psychological dimensions and revealed differences between IIs in patterns of cue utilization.     

Temporal-order judgments and reaction time for stimuli of different modalities

Summary Reaction times and the relative latency evaluated by the temporal-order-judgment method for two stimuli of different modalities (visual and auditory) were measured. The difference between reaction times for visual and auditory stimuli was about 40 ms. The relative latency was slightly shorter, however; in conflict with Rutschmann and Link's (1964) previous result, the auditory stimulus must be delayed to be perceived simultaneously with the visual one.     

Interobserver agreement and procedural fidelity: An odd asymmetry

We examined articles with experiments published in the Journal of Applied Behavior Analysis and in Behavior Analysis in Practice from 2017 through 2021 to determine how frequently procedural fidelity was assessed. When procedural fidelity was assessed, we determined how often a measure of interobserver agreement for those fidelity data was provided. We also determined how often a measure of interobserver agreement for participants' behavior was provided. Across both journals and all years, 54.7% of relevant articles provided a measure of procedural fidelity. Of them, 17.7% provided a measure of interobserver agreement for procedural fidelity. In marked contrast, 96.4% provided interobserver agreement data for participants' behavior. It is unfortunate that applied behavior analysts frequently fail to provide procedural fidelity data and, when they do, often fail to provide interobserver agreement data for the fidelity data. Reviewers for, and editors of, behavior-analytic journals are encouraged to strongly consider the relative value of procedural fidelity and agreement on procedural fidelity measures when rendering recommendations on the suitability of a given submission.     

Choice reaction times in children: Error and post-error responses,and the repetition effect

Analysis of the frequency and nature of error and post-error responses in the serial choice reaction times (RTs) of children between 5 and 12 years essentially replicate findings in adults. Errors are few and fast, tend to be made on fingers closely related to the correct responding finger, and are followed by a marked slowing in response rate. This pattern of results is interpreted in terms of a strategy to optimize performance with respect to instructions emphasizing both speed and accuracy. Importantly, this may be seen to reflect the activity, even in the youngest of children, of a finely-tuned feedback mechanism for error detection. Only the extent of immediate post-error slowing shows a decline with age, and is referred to improvements in response programming. Repetition RT is much faster than alternation RT (the “Repetition Effect”) and improves much less rapidly with age. Reduction of the Repetition Effect with age is consistent with theories of RT in which signals are categorized by retrospective search in short-term memory. The girls' advantage in gross RT is found to be confined to alternation RT only. The particular contribution of alternation RT both to the development of, and sex difference in, gross RT is related to the greater response organization involved in rapidly switching between fingers and hands.     

Encoding fluency is a cue used for judgments about learning

The authors used paired-associate learning to investigate the hypothesis that the speed of generating an interactive image (encoding fluency) influenced 2 metacognitive judgments: judgments of learning (JOLs) and quality of encoding ratings (QUEs). Results from Experiments 1 and 2 indicated that latency of a keypress indicating successful image formation was negatively related to both JOLs and QUEs even though latency was unrelated to recall. Experiment 3 demonstrated that when concrete and abstract items were mixed in a single list, latency was related to concreteness, judgments, and recall. However, item concreteness and fluency influenced judgments independently of one another. These outcomes suggest an important role of encoding fluency in the formation of metacognitive judgments about learning and future recall.     

Voice reaction times with recognition for Commodore computers

Hardware and software modifications are presented that allow for collection and recognition by a Commodore computer of spoken responses. Responses are timed with millisecond accuracy and automatically analyzed and scored. Accuracy data for this device from several experiments are presented. Potential applications and suggestions for improving recognition accuracy are also discussed.     

The effect of blinks and saccadic eye movements on visual reaction times

Vision is suppressed during blinks and saccadic eye movements. We hypothesized that visual reaction times (RTs) in a vigilance test would be significantly increased when a blink or a saccade happened to coincide with the stimulus onset. Thirty healthy volunteers each performed a visual RT test for 15 min while their eye and eyelid movements were monitored by a system of infrared reflectance oculography. RTs increased significantly, many by more than 200 msec, when a blink occurred between 75 msec before and up to 150 msec after the stimulus onset. A similar result was observed with saccades that started 75 to 150 msec after the stimulus. Vision or attention was evidently inhibited before each blink and for longer than the saccades lasted. We suggest that visual suppression is involved in this process, which could explain some of the normal variability in RTs over periods of seconds that has not been adequately explained before.