The enduring effect of availability

The present study addressed whether experienced ease of retrieval of autobiographical events affects trait judgments made immediately and after a delay (Experiment 1) and whether this influence is modulated by either of two discounting instructions (Experiment 2). In Experiment 1, participants first attempted to retrieve 6 or 12 personal memories for different traits and then made ease of retrieval and self-trait judgments immediately or 1 week later. In Experiment 2, participants made immediate ratings and then delayed ratings under 3 instructional manipulations: a generic instruction to repeat these judgments, to make these ratings after they were reminded of their original recall total, or to make these ratings after they had their retrieval ease discounted or augmented. In each experiment, an enduring effect of availability was obtained in that the relationship between ease of retrieval and self-trait rating was only slightly affected by the delay. Being reminded of the original number of recalled memories nullified the relationship between ease of retrieval and trait rating. However, discounting or augmenting ease of retrieval, which altered ease of retrieval ratings, did not. Potential explanations for an enduring effect of availability are discussed.     

The availability explanation of excessive plausibility assessments

The assessment of hypotheses in hypothesis generation involves a comparison between those hypotheses that have been generated (specified) and those that are not generated (unspecified). Experiment 1 was an investigation of an “availability explanation” for subjects' overconfidence in the probability of specified hypotheses. The conjecture is that subjects have difficulty retrieving unspecified hypotheses from memory. Therefore, the underpopulated set of unspecified hypotheses is assessed as less probable then it actually is and the specified set is assessed as more probable. Two manipulations to increase the availability of unspecified hypotheses were investigated. One involved explicitly requesting subjects to populate the unspecified set; the other was a computer presentation of candidate unspecified hypotheses. Results of experiment 1 were that assessment overconfidence for both experimental groups was reduced. The results support the conjecture that the availability heuristic is at least partially responsible for subjects' overconfidence. The main result of experiment 2 was that the overconfidence bias persisted with different assessment methods for both subject-generated and experimenter-supplied hypotheses.     

The effect of availability heuristics in online consumer reviews

This research investigates principles of judgmental heuristics and dual processing systems in the online purchasing environment. It examines the effects of availability cues in restaurant reviews on dining intentions and menu item choice. Two experiments are reported in which consumers make dining out and food choice decisions using simulated online review sites. The first experiment evaluates primacy–recency effects of positive and negative reviews along with different review types. The findings indicate that text plus ratings produce higher visit intentions and expectations compared with either cue by itself. The second experiment examines the effects of rating format, visual cues, and review valence on menu item choice. Pictures increase likelihood to choose a positively reviewed menu item but do not influence likelihood to choose a negatively reviewed item. This finding supports the negativity bias, whereby consumers place more weight on negative versus positive information. Consumers are more likely to choose a menu item with pictures when ratings are in numerical versus star rating format. The findings can be interpreted in terms of System 1 (heuristic) and System 2 (systematic) processing.     

The effects of brief and extended stimulus availability on preference

The effects of stimulus availability on preference were evaluated using two conditions of a modified preference assessment. Different preference hierarchies were found in 15-s access conditions than in 15-min access conditions. Subsequent comparisons of a short-availability high-preference stimulus and a long-availability high-preference stimulus verified differential preferences for stimuli based on duration of availability.     

The availability heuristic with famous names: a replication

In two experiments, 195 Canadian undergraduates initially judged a list of 25 names (12 famous men and 13 nonfamous women or 12 famous women and 13 nonfamous men) for familiarity. Contrary to previous research, subsequent estimates of the perceived number of men's and women's names were not higher when the names were famous than nonfamous. When the estimated differences were compared to the true difference (-1), famous names were judged more numerous than nonfamous names, but the size of the effect (d = 0.34) was smaller than in previous research. Reasons for these findings are discussed.     

Knowledge and availability

The mentioning of error-possibilities makes us less likely to ascribe knowledge. This paper offers a novel psychological account of this data. The account appeals to “subadditivity,” a well-known psychological tendency to judge possibilities as more likely when they are disjunctively described.     

The effect of signaled reinforcement availability on concurrent performances in humans

During Phase I, three female human subjects pressed a button for monetary reinforcement in two-component concurrent variable-interval schedules. Five different reinforcement frequencies were used in component A, whereas the reinforcement frequency in component B was held constant. Absolute rates of responding conformed to equations proposed by Herrnstein to describe concurent performances, and the ratios of the response rates and the times spent in the two components conformed to the matching law. During Phase II, the availability of reinforcement in component A was signaled by the illumination of a lamp. This resulted in suppression of response rates in component A and elevation of response rates in component B, these changes being reflected in a distortion of the matching relationship which took the form of a bias in favor of component B.     

Less is more: The availability heuristic in early childhood

This study examined whether young children are influenced by the subjective experience associated with an easy or difficult recall when making memory decisions. Seventy‐one children, aged 4, 6, and 8 years, were asked to generate either a small (easy condition) or large (hard condition) number of first names. Statistical analyses revealed that participants in the hard condition were more likely to infer that they did not know many names than participants in the easy condition, contrary to what would be expected if children based their memory judgement on the objective number of recalled items. Overall, our results support the hypothesis that children as young as 4 years old rely on the subjective experience of ease to regulate their decision‐making processes. Theoretical implications of these findings are discussed.     

Cognitive aspects of lexical availability

Lexical availability measures the ease with which a word can be generated as a member of a given category. It has been developed by linguistic studies aimed, among other things, at devising a rational basis for selecting words for inclusion in dictionaries. The measure accounts for the number of people who generated a given word as a member of a designated semantic category and the position in which they produce the word. We present an analysis of lexical availability from a cognitive perspective. Data were analysed for Spanish speakers generating words from five semantic categories—clothes, furniture, body parts, animals, and intelligence. Six properties of words were investigated as potential predictors of lexical availability. Predictors were concept familiarity, typicality, imageability, age of acquisition, word frequency, and word length. Categories differed on these variables, and regression analysis found concept familiarity, typicality, and age of acquisition to be significant predictors of lexical availability. The cognitive basis of these findings and the practical consequences of selecting words on the basis of lexical availability are considered.     

The availability of useful information to the right of fixation in reading

A series of experiments that examined the characteristics of useful information to the right of fixation during reading is reported. In Experiments 1 and 2, reading performance when the information available to the right of fixation was determined by a fixed number of letters was compared with reading performance when the information to the right of fixation was determined by a fixed number of words. Beyond making more letters visible, both experiments showed that preserving all of the letters of a word was of no special benefit to reading. By explicitly presenting parts of the word to the right of fixation as well as the fixated word, Experiments 3 and 4 followed up on the implication that readers utilize partial letter information from words. Both experiments showed that reading was improved by this partial information and that preserving three letters of the word to the right of fixation improved reading almost as much as presenting the entire word. The implications the results have for models of reading are discussed.     

The effect of stimulus availability on task choice in voluntary task switching

The voluntary task switching paradigm allows subjects to choose which task to perform on each trial in a stimulus environment affording multiple tasks. The present study examined the effect of stimulus availability on task choice. Subjects viewed displays containing a digit and a letter and performed either an even/odd or a consonant/vowel judgment on each trial. The target stimuli appeared with a stimulus onset asynchrony (SOA) of 0, 50, 100, or 150 msec. The probability of performing the task associated with Stimulus 1 increased as SOA increased, indicating an effect of external or stimulus-driven factors on task choice. This effect of stimulus availability on task choice was greater when the response-stimulus interval was 400 msec than when it was 2,000 msec. This interaction of preparation interval and stimulus availability is explained within a model of task choice that includes both internal processes and external influences.     

Syntactic and semantic processes in aphasic deficits: The availability of prepositions

The availability of a specific category of closed class items (prepositions) was examined in Broca's and Wernicke's aphasia. The role of prepositions was varied (syntactic/semantic) in two tasks: one requiring production of prepositions and the other acceptability judgments. Overall, it was easier to perform the acceptability task than to produce the target item. In the judgment task, Wernicke's aphasics more accurately determined the acceptability of prepositions in their syntactic role than in their semantic role, but Broca's aphasics showed no such difference. In the production task, Wernicke's aphasics again were more likely to produce prepositions which were in a primarily syntactic role. Broca's aphasics, however, failed to produce such syntactically based prepositions. The results suggest that the availability of a given closed class vocabulary form is not merely a function of its class membership but also of its functional role, and this fact serves to distinguish aspects of Broca's and Wernicke's aphasics' deficit.     

The concreteness effect: evidence for dual coding and context availability

The term concreteness effect refers to the observation that concrete nouns are processed faster and more accurately than abstract nouns in a variety of cognitive tasks. Two models have been proposed to explain the neuronal basis of the concreteness effect. The dual-coding theory attributes the advantage to the access of a right hemisphere image based system in addition to a verbal system by concrete words. The context availability theory argues that concrete words activate a broader contextual verbal support, which results in faster processing, but do not access a distinct image based system. We used event-related fMRI to detect the brain regions that subserve to the concreteness effect. We found greater activation in the lower right and left parietal lobes, in the left inferior frontal lobe and in the precuneus during encoding of concrete compared to abstract nouns. This makes a single exclusive theory unlikely and rather suggests a combination of both models. Superior encoding of concrete words in the present study may result from (1) greater verbal context resources reflected by the activation of left parietal and frontal associative areas, and (2) the additional activation of a non-verbal, perhaps spatial imagery-based system, in the right parietal lobe.     

The availability heuristic in person identification: The sometimes misleading consequences of enhanced contextual information

Three field studies investigated the effects of post-exposure cognitions on person identification. Subjects' beliefs that they could identify someone were significantly increased by the presentation of new information and the rehearsal of old information about the person. Misidentification errors increased as the lengths of the initial exposure duration increased and when subjects received additional contextual information about the target. These frequent misidentifications may reflect the misattribution of familiarity from enhanced contextual knowledge to familiarity arising from perceptual knowledge. Further, performance was enhanced when the identification task capitalized on 'transfer-appropriate rehearsal' post-event strategies. Ancillary findings contradicted research on 'verbal overshadowing', and the relationship between identification accuracy and confidence. The results were generalized to real-world situations that encourage post-event cognitions by eyewitnesses.     

Probability matching in risky choice: The interplay of feedback and strategy availability

Probability matching in sequential decision making is a striking violation of rational choice that has been observed in hundreds of experiments. Recent studies have demonstrated that matching persists even in described tasks in which all the information required for identifying a superior alternative strategy—maximizing—is present before the first choice is made. These studies have also indicated that maximizing increases when (1)?the asymmetry in the availability of matching and maximizing strategies is reduced and (2)?normatively irrelevant outcome feedback is provided. In the two experiments reported here, we examined the joint influences of these factors, revealing that strategy availability and outcome feedback operate on different time courses. Both behavioral and modeling results showed that while availability of the maximizing strategy increases the choice of maximizing early during the task, feedback appears to act more slowly to erode misconceptions about the task and to reinforce optimal responding. The results illuminate the interplay between “top-down” identification of choice strategies and “bottom-up” discovery of those strategies via feedback.     

The influence of rule availability and item similarity on metacognitive monitoring during categorisation

In four experiments, we examined the sources of metacognitive judgments during the categorisation of new items after the learning of old items was completed. In the rule condition, the categorisation rule was explicitly given to the participants during learning, while in the no-rule condition participants relied on feedback to infer category membership. In the transfer phase, two types of novel items were used: good and bad transfer items. Transfer items also differed in the level of similarity to their training pairs. In the rule condition, all types of transfer items were classified with high accuracy and confidence. In the no-rule condition, a dissociation between accuracy and confidence was revealed. Good transfer items were classified more accurately than bad transfer items, whereas similar items were classified with higher confidence than dissimilar items. The obtained results suggest the utilisation of two potential cues for metacognitive judgments: declarative knowledge if the correct rule is explicitly available, and item similarity if it is difficult to infer the correct rule from feedback.