The role of expectancy in comparative judgments

Researchers interested in the processing of relational information have sought a satisfactory explanation for the congruity effect in linear orders. It is relatively easy to select either the greater of two objects that are high on a dimension or the lesser of two objects that are low on a dimension, but it is relatively difficult to determine the greater of two objects that are low in magnitude or the lesser of two objects that are high in magnitude. One explanation of the congruity effect is the expectancy hypothesis that claims that the choice of the comparative primes objects of particular magnitudes. We present two experiments that demonstrate that a congruity effect of equivalent magnitude is obtained when the comparative is presented after the stimulus pair. Moreover, this equivalence cannot be attributed to the salience of the dimensions we employed, because this equivalence held for stimuli that were classified as salient and for those classified as nonsalient. These findings are interpreted in the context of some current explanations of the congruity effect.     

Semantic congruity in symbolic comparisons: Evidence against an expectancy hypothesis

A previously proposed expectancy hypothesis predicts that the semantic congruity effect typically observed in symbolic comparison tasks will be eliminated when the items to be compared are presented prior to the comparative. Previous studies testing this hypothesis have been inconclusive. The present experiments demonstrate that a semantic congruity effect can be obtained when the comparative follows the pair after a 1-sec (Experiment 1) or 4-sec (Experiment 2) delay. Lexical markedness effects were also obtained. The key to producing a “comparative-after” congruity effect is to intermix questions about several different dimensions, so that when the pair is presented, subjects will be unable to anticipate the question. The results disconfirm the expectancy hypothesis.     

Semantic congruity and expectancy as separate processes

In two experiments, we investigated the role of expectancy in producing congruity effects in comparative judgment. In Experiment 1, instructions to choose the larger or smaller term either preceded pairs for comparative judgment or preceded individual words for lexical decision. If expectancy in interpreting the comparative judgment terms accounts for the congruity effect, the lexical decision task also should show a congruity effect. However, there were large congruity effects in comparative judgment but not in lexical decision. In this experiment, we used an infiniteset design to make sure that semantic information was needed on comparative judgment trials. In Experiment 2, comparative judgment pairs were preceded by a prime word that either was or was not a category label for the terms in the pairs. There were both congruity and priming effects, with no interaction between the two. This result implies that expectancy and the semanticcongruity effect come from separate processes.     

Semantic congruity and lexical marking in symbolic comparisons: An expectancy hypothesis

Lexical marking and semantic congruity effects were investigated in four symbolic size comparison experiments. Predictions followed from an expectancy hypothesis suggested by results of recent comparative judgment studies. According to the present position, lexical marking and semantic congruity should be mutually exclusive effects in such tasks, and the demonstration of either dependent upon the order in which the stimuli and the comparative term are evaluated. When the comparative precedes the stimuli, an expectancy is created whereby the subject is more likely to be prepared for, say, large items following the comparative “larger” and small items following the comparative “smaller.” In addition, the usual advantage of unmarked as compared to marked comparisons should be offset by the initial processing of the comparative. As predicted, the comparative-stimulus presentation order produced a significant semantic congruity effect and no effect of lexical marking in Experiment 1. Conversely, when stimuli precede the comparative, or are presented simultaneously with it, no expectancy should be created, as the items are immediately available to the subject, and the semantic congruity effect should not be obtained. Upon presentation of the comparative, however, unmarked comparisons should be easier than marked comparisons. Experiments 2 and 4 confirmed these expectations, as significant lexical marking effects were obtained and significant congruity effects were not. These findings are contrary to predictions derived from a semantic coding interpretation of the symbolic comparison process.     

Mental comparison of size and magnitude: size congruity effects

Paivio (1975) found that the latency to choose the larger of two named objects does not depend on congruity between the object sizes and the sizes of the object names. Because size congruity does affect latencies for pictorially presented objects, Paivio interpreted this result as support for the dual coding hypothesis. However, Experiment 1 demonstrated that Paivio's results were an artifact of his experimental design. Size congruity does affect latencies to choose the larger of two named objects when object pairs are not repeated. When the same object pairs are used repeatedly, as in Paivio's experiment, the effect disappears. In this case the response is probably remembered, so that the objects need not be compared. To determine the processing stages affected by size congruity, both the distance between stimulus sizes and the size congruity were manipulated in Experiment 2. Three groups of subjects chose either the greater Arabic digit, the greater named digit, or the larger named object. Size congruity interacted with distance only for Arabic digits. For both Arabic digits and named digits, the interference caused by size incongruity was greater than the facilitation caused by size congruity, whereas for object names, the facilitation was greater than the interference. A model of the interaction between physical size comparisons and conceptual size comparisons is proposed to account for these results.     

Semantic congruity and expectancy in symbolic judgments

These experiments assess the degree to which the semantic-congruity effect in comparative judgment can be explained by such expectancy effects as priming, perceptual "set," or strategies used in the task. The first experiment mixed a lexical-decision task with the comparative-judgment task and showed that neither automatic semantic priming nor deliberate preparation can account for the congruity effect. Experiments 2-4 assessed expectancy effects in a different way by presenting the instructions for comparative judgment either before or after the pair to be judged. These experiments included, among other things, a number of safeguards against artifacts in this paradigm. In these three experiments the congruity effect was obtained with both orders of stimuli and instructions, contrary to the prediction of an expectancy hypothesis. The results indicate that when stimuli are not degraded. The semantic-congruity effect depends largely on the relation between the stimuli and the instructions and only to a small degree, if at all, on expectancy.     

Evidencefor implicitscaling in comparative judgment

In two experiments, we examined the effects of manipulating the density of stimuli on comparison difficulty in a comparative judgment task. In Experiment 1, subjects were slower at judging the relative size of a pair when the members were adjacent items in the linear order than when the members were separated by items of intervening magnitudes. In Experiment 2, the advantage of choosing the larger rather than the smaller of two large-stimuli (e.g., the congruity effect) increased when the linear order included many small items. In contrast, the advantage of choosing the smaller of two small items increased when the linear order included many large items. The applicability of the range-frequency theory (Parducci,1965) to these results is discussed.     

Comparing 5/7 and 2/9: Adults can do it by accessing the magnitude of the whole fractions

This study investigated adults' ability to compare the magnitude of fractions without common components (e.g., 5/7 and 3/8), and the representation accessed in that process. We hypothesized that the absence of common components would enhance access to the magnitude of the fractions (i.e., a holistic representation) rather than a direct comparison of the numerators or the denominators. This hypothesis was tested in four between-subject conditions. Two types of experimental pairs were used that differed in the congruity of the magnitude of the denominator and the magnitude of the fraction. Each type of experimental pair was presented either alone or with filler pairs that introduced variability into the congruity of the components. In all four conditions, accuracy was above chance and the effect of the distance between the fractions on response times was significant, indicating an access to the magnitude of the fractions. Nevertheless, the variability of the congruity of the components had also a significant effect on performance, suggesting that the relative magnitude of the components was also processed. In conclusion, the representation of the fraction magnitude is hybrid, rather than purely holistic, in a magnitude-comparison task on fractions without common components.     

Automatic comparisons of artificial digits never compared: learning linear ordering relations

In 2 experiments, participants were trained to perform magnitude decisions, that is, decide which of 2 arbitrary symbols in a pair represented a larger magnitude. The symbols corresponded to locations on an implicit linear scale. Training resulted in a Stroop-like size congruity effect when the participants had to decide which symbol in a pair was physically larger. This effect, showing automaticity of the processing of magnitude relations, was also obtained for pairs never encountered during practice. The implications of these findings for processing of magnitude relations and for theories of automaticity are discussed.     

Order information in dichotic memory.

Three experiments were performed using a recognition probe procedure to test the subject's recognition of the order of two items from a dichotically presented list. In all three experiments subjects were unable to recognize simultaneous items as having been simultaneous unless the critical pair was the last pair in the list. In contrast, they were able to identify the order of items not originally presented simultaneously at better than a chance level. Performance did not differ as a function of whether the two critical items were presented to the same or different ears. The data were interpreted as indicating that subjects divide attention between competing inputs in the dichotic memory task and that the eary-by-ear order of report is a result of the format in which the items are stored.     

The influence of retrieval on retention

Four experiments tested the hypothesis that successful retrieval of an item from memory affects retention only because the retrieval provides an additional presentation of the target item. Two methods of learning paired associates were compared. In the pure study trial (pure ST condition) method, both items of a pair were presented simultaneously for study. In the test trial/study trial (TTST condition) method, subjects attempted to retrieve the response term during a period in which only the stimulus term was present (and the response term of the pair was presented after a 5-sec delay). Final retention of target items was tested with cued-recall tests. In Experiment 1, there was a reliable advantage in final testing for nonsense-syllable/number pairs in the TTST condition over pairs in the pure ST condition. In Experiment 2, the same result was obtained with Eskimo/English word pairs. This benefit of the TTST condition was not apparently different for final retrieval after 5 min or after 24 h. Experiments 3 and 4 ruled out two artifactual explanations of the TTST advantage observed in the first two experiments. Because performing a memory retrieval (TTST condition) led to better performance than pure study (pure ST condition), the results reject the hypothesis that a successful retrieval is beneficial only to the extent that it provides another study experience.     

The psychophysics of numerical comparison: a reexamination of apparently incompatible data

Reaction-time studies of numerical comparison have used essentially two paradigms: classification, in which a target number must be labelled "larger" or "smaller" in comparison to a fixed standard, and selection, in which the larger (or smaller) number of a pair must be picked out. In previous studies, classification has yielded only a distance effect in RTs, whereas selection has also revealed magnitude (or minimum) and congruity effects. We used two experiments with two-digit number comparisons to find the reason for this discrepancy. In Experiment 1, we used a variant of the classification task with the standard changing on each trial. RTs increased along with the standard for "smaller" responses and decreased along with the standard for "larger" responses, in a manner reminiscent of magnitude and congruity effects. In Experiment 2, we again used classification, but the fixed standard 75 was not at the center of the range of target numbers (20, 21, ... 99). Close to the standard, RTs were faster for "larger" than for "smaller" responses, again a congruity effect. Our data show that magnitude and congruity effects can be obtained with two-digit numbers in classification as well as in selection tasks. A single equation, which implies that numbers are compared with respect to reference points at both ends of the continuum, describes the results from both tasks.     

Semantic congruity effects in perceptual comparisons

Semantic congruity effects occur when, as in Experiment 1, for example, the time to select the shorter of two relatively short lines is faster than the time to select the longer; conversely, selection of the longer of two relatively long lines is faster than selection of the shorter. Semantic congruity effects are also demonstrated in experiments requiring comparisons of the heaviness of weights (Experiment 2) and horizontal extent (Experiment 3). In Experiment 1, the magnitude of the semantic congruity effect was larger under conditions emphasizing accuracy rather than speed and when the comparison was difficult. In fact, when comparisons were errorless, the effect was minimal (20 msec), thereby replicating previous failures to obtain the effect with supraliminal perceptual comparisons (Banks, Mermelstein, & Yu, 1982; Marschark & Paivio, 1981; Petrusic & Baranski, 1988a). In confirmation of Henmon's (1911) introspective analyses of psychophysical comparisons, Experiments 2 and 3 extend the range of the semantic congruity effect to include judgments of confidence. However, in each of the three experiments, semantic congruity effects were not evident with the response-accuracy measure. Finally, using highly confusable stimuli, in Experiment 3 the magnitude of the semantic congruity effect was shown to be larger for error than for correct response times. The implications of these findings for a decisional locus of the effect and for the semantic coding theory are discussed.     

Adults' acquisition of novel dimension words: creating a semantic congruity effect

The semantic congruity effect is exhibited when adults are asked to compare pairs of items from a series, and their response is faster when the direction of the comparison coincides with the location of the stimuli in the series. For example, people are faster at picking the bigger of 2 big items than the littler of 2 big items. In the 4 experiments presented, adults were taught new dimensional adjectives (mal/ler and borg/er). Characteristics of the learning situation, such as the nature of the stimulus series and the relative frequency of labeling, were varied. Results revealed that the participants who learned the relative meaning of the artificial dimensional adjectives also formed categories and developed a semantic congruity effect regardless of the characteristics of training. These findings have important implications for our understanding of adult acquisition of novel relational words, the relationship between learning such words and categorization, and the explanations of the semantic congruity effect.     

Congruity and the perceptual comparison task

The effects of congruity between comparatives and the relative magnitudes of to-be-compared stimuli were investigated in six perceptual comparison experiments. Experiments 1-5 failed to obtain congruity effects in purely perceptual tasks even when subjects had extensive practice with a relatively small stimulus set. Experiment 6 obtained a congruity effect with perceptual stimuli but only when the stimuli were described as representing real-world objects. All of the results indicated that congruity effects occur only in tasks that include major symbolic or memorial components; a review of the perceptual comparison literature reveals consistent support for this position. These findings are discussed in terms of expectancy and semantic coding interpretations of the congruity effect.     

Categorization processes in mental comparisons

Five experiments explore categorization and category-based congruity effects in mental comparisons. The first 4 experiments concentrate on categorization of infinite-set small items. The experiments vary the additional items presented and whether those items appear once (Experiments 1-2) or repeatedly (Experiments 3-4). Additional items include other small items (Experiment 1), relatively large items (Experiments 2-4), and items involving nonsize dimensions (Experiment 4). The critical small items show a complete congruity effect only in Experiments 1 and 3. Results suggest that categorization of infinite-set items may be based on range information alone (Experiment 1) but that multiple categorizations based on multiple ranges (Experiment 2) may require attentional effort. Results implicate categorization as a central process in mental comparison, despite differences in ease of categorization across paradigm.     

Adults' Acquisition of Novel Dimension Words: Creating a Semantic Congruity Effect

The semantic congruity effect is exhibited when adults are asked to compare pairs of items from a series, and their response is faster when the direction of the comparison coincides with the location of the stimuli in the series. For example, people are faster at picking the bigger of 2 big items than the littler of 2 big items. In the 4 experiments presented, adults were taught new dimensional adjectives (mal/ler and borg/er). Characteristics of the learning situation, such as the nature of the stimulus series and the relative frequency of labeling, were varied. Results revealed that the participants who learned the relative meaning of the artificial dimensional adjectives also formed categories and developed a semantic congruity effect regardless of the characteristics of training. These findings have important implications for our understanding of adult acquisition of novel relational words, the relationship between learning such words and categorization, and the explanations of the semantic congruity effect.     

The role of part—whole information in reasoning about relative size

Models of comparative judgment have assumed that relative magnitude is computed from knowledge about absolute magnitude rather than retrieved directly. In Experiment 1, participants verified the relative size of part-whole pairs (e.g., tree-leaf) and unrelated controls (e.g., tree-penny). The symbolic distance effect was much smaller for part-whole pairs than for unrelated controls. In two subsequent experiments, participants determined either which of two objects was closer in size to a third object or which of two pairs had a greater difference in the size of its constituents. In contrast to the paired comparison task in Experiment 1, judgments of part-whole items were more sensitive to the influence of symbolic distance than were unrelated controls. The fact that the part-whole relation attenuates the effects of symbolic distance in a paired comparison task but not in tasks that require an explicit comparison of size differences suggests that the part-whole relation provides a source of information about relative magnitude that does not depend on knowledge about absolute magnitude.     

The role of categorical information in processing relational attributes

In two experiments, the effect of knowledge about relevant common taxonomic categories on judgments of relative magnitude was investigated. In Experiment 1, subjects judged the relative size of objects that belonged to the categoriesbuilding andanimal. The symbolic distance effect was smaller for between-category pairs (e.g.,horse-cabin) whose members could be classified more quickly into the two categories. This result strongly suggests that subjects used category membership to determine relative size on at least some portion of the trials. In Experiment 2, a similar attenuation of symbolic distance was obtained when subjects judged the relative height of furniture and vehicles. A simple explanation of the reduced symbolic distance effect for between-category pairs is that subjects occasionally fail to categorize the items into different categories and have to compute relative magnitude from the magnitudes of the two items. Fits to the data using the bootstrap technique suggest that more involved assumptions are required.     

Event-related potentials and the interaction between orthographic and phonological information in a rhyme-judgment task

Event-related potentials (ERPs) were recorded from one midline and three pairs of lateral electrodes in three experiments involving a rhyme-judgment task. Experiment 1 employed sequentially presented word pairs consisting of orthographically similar and dissimilar rhyming and nonrhyming items (RUNG-SUNG, MAKE-ACHE, BEAD-DEAD, GIFT-ROAD). Comparison of the ERPs elicited by the dissimilar pairs revealed a rhyme/nonrhyme difference in the form of an increase in the amplitude of a late negative component (N450) for nonrhyming pairs; this effect was confined almost entirely to right-hemisphere electrodes. By contrast, rhyme/nonrhyme differences in the ERPs to orthographically similar word pairs were smaller in magnitude, later in onset, and bilaterally distributed. Experiment 2 showed that this pattern of ERP effects with orthographically similar items depended upon orthographic and not visual similarity. Experiment 3 tested the hypothesis that the lack of a right-hemisphere based N450 effect with orthographically similar items resulted from the operation of an orthographic priming mechanism. ERPs to nonrhyming pairs containing a word with an inconsistent segment (COAST-FROST) were compared with visually matched controls (SPARSE-CREASE). The rhyme/nonrhyme differences in the N450 components from these two conditions were indistinguishable, although subjects found it as difficult to make nonrhyme responses to "COAST-FROST" pairs as to the orthographically similar nonrhyming items in Experiment 1. It was concluded that while "orthographic priming" accounted for the behavioral data from these experiments, it could not explain the interaction between phonology and orthography observed in the concurrently recorded ERP data.