The role of familiarity in determining typicality

Ashcraft (1978b) found that people tend to know more properties of instances they rate as typical of a category than of instances they rate as atypical. This suggests that variations in typicality result from variations in familiarity. Three experiments are presented that challenge or qualify this suggestion. Experiment 1 showed that subjects sometimes produce more properties for items they rate as low in typicality. Experiment 2 showed that in a large, random sample of items, there was a tendency to produce fewer properties for atypical items, but Experiment 3 indicated that part of the reason for this result was a response bias to assign low typicality ratings to unfamiliar words, rather than a reflection of low perceived typicality of the referents themselves. These results suggest that variations in typicality can exist independent of variations in familiarity, although familiarity may also play a role.     

Understanding the effects of sample size on the variability of the mean

In the first three experiments, we attempted to learn more about subjects' understanding of the importance of sample size by systematically changing aspects of the problems we gave to subjects. In a fourth study, understanding of the effects of sample size was tested as subjects went through a computerassisted training procedure that dealt with random sampling and the sampling distribution of the mean. Subjects used sample size information more appropriately for problems that were stated in terms of the accuracy of the sample average or the center of the sampling distribution than for problems stated in terms of the tails of the sampling distribution. Apparently, people understand that the means of larger samples are more likely to resemble the population mean but not the implications of this fact for the variability of the mean. The fourth experiment showed that although instruction about the sampling distribution of the mean led to better understanding of the effects of sample size, subjects were still unable to make correct inferences about the variability of the mean. The appreciation that people have for some aspects of the law of large numbers does not seem to result from an in-depth understanding of the relation between sample size and variability.     

Interpreting statistical testing: Process and propensity, not population and random sampling

The standard textbook treatment of conventional statistical tests assumes random sampling from a population and interprets the outcome of the statistical testing as being about a population. Problems with this interpretation include that (1) experimenters rarely make any attempt to randomly sample, (2) if random sampling occurred, conventional statistical tests would not precisely describe the population, and (3) experimenters do not use statistical testing to generalize to a population. The assumption of random sampling can be replaced with the assumption that scores were produced by a process. Rejecting the null hypothesis then leads to a conclusion about process, applying to only the subjects in the experiment (e.g., that some difference in the treatment of two groups caused the difference in average scores). This interpretation avoids the problems noted and fits how statistical testing is used in psychology.     

Subjective shortening in humans' memory for stimulus duration

Three experiments investigated memory for stimulus duration in humans using a modification of a delayed-matching technique previously used to study event memory in pigeons. In a session of 48 discrete trials subjects were presented with a sample stimulus (a 500-Hz tone with mean duration of 400 msec) then a comparison stimulus (the same duration as the sample, or longer or shorter), after a delay that was 1 to 10 sec in Experiments 1 and 2, and 2 to 16 sec in Experiment 3. After the comparison had been presented, subjects judged whether the sample and comparison had the same duration (a YES/NO decision, Experiment 1), or whether the comparison was longer, shorter, or of the same duration as the sample (Experiments 2 and 3). Overall, mean number of correct responses changed little with increases in the delay, but the change of number of correct responses with delay was markedly different on trials in which the sample and comparison were the same, the comparison was shorter, or the comparison was longer. In general, accuracy declined with increasing delay in the first case, remained constant in the second case, and increased when the comparison was longer than the sample. Examination of the types of errors made on the different sorts of trials (Experiment 3) suggested that the data were produced by two mechanisms: (1) subjective shortening of the sample as the delay between sample and comparison increased, and (2) a time-order error to respond that the sample was longer than the comparison. Overall, it appears that humans' working memory for duration exhibits a subjective shortening effect similar to that previously found in pigeons.     

Solving problems by analogy: The benefits and detriments of hints and depressed moods

In Experiment 1, mildly depressed (dysphoric) and nondysphoric subjects tried to solve logic problems that were analogous to subsequent target problems; then they attempted target solutions with or without hints in the form of the anologues’ themes. Target solutions were impaired by the hints in the nondysphoric group alone. Experiment 2A was a no-training control to verify that transfer did indeed occur. In Experiment 2B, all subjects received hints in the transfer phase; the training phase was either problem oriented (as in Experiment 1) or memory oriented. Again, nondysphoric subjects solved fewer problems following problem-oriented training than did both dysphoric subjects in that condition and nondysphoric subjects with memory-oriented training. Experiment 3 replicated the previous results in the nondysphoric samples. We interpret these findings within the transferappropriate processing framework.     

Acquisition of arbitrary conditional discriminations by young normally developing children

Three experiments investigated conditions designed to facilitate acquisition of arbitrary conditional discriminations in 3- to 6-year-old normally developing children. In Experiment 1, 6 subjects failed to master the arbitrary match-to-sample task under conditions of differential reinforcement alone, but 7 subjects did so when instructions or instructions and sample naming were added. In Experiment 2, sample naming introduced in a blocked-trial arrangement resulted in acquisition, but only when the sample name was a nonsense syllable provided by the experimenter (5 of 7 subjects) and not when the sample name was generated by the subject (0 of 5 subjects). Experiment 3 demonstrated the effectiveness of a training sequence involving thematically related stimuli as an intermediate step facilitating the transition from identity to novel arbitrary relations. The difficulties in mastering arbitrary conditional discriminations shown here imply that further analyses with young children will be particularly important in efforts to investigate the development of theoretically important stimulus relations.     

Spatial-frequency-dependent visible persistence and specific reading disability

Visible persistence duration for sine-wave gratings was measured in 9-year-old normal and specific-reading-disabled children. Experiment 1 investigated the influence of stimulus duration on visible persistence. The results demonstrated a Reading Group X Spatial Frequency interaction with disabled readers showing a smaller increase in persistence duration with increasing spatial frequency than controls. This interaction was greatest with stimulus durations longer than 80 msec. In Experiments 2a and 2b persistence was measured across a range of contrasts from .1 to .5. The stimulus durations employed were 100 msec in Experiment 2a and 300 msec in Experiment 2b. In both experiments, increasing contrast decreased persistence duration at 2 and 12 cycles per degree (c/deg) for the control group. In the specific-reading-disabled group, however, contrast had little effect on the persistence of 2-c/deg gratings in either experiment. In Experiment 2a the persistence of the 12-c/deg grating decreased with increasing contrast for both groups. In Experiment 2b contrast had significantly less effect on persistence duration in the specific-reading-disabled group, however, contrast had little effect on the persistence of 2-c/deg ratings in either experiment. In Experiment 2b contrast had significantly less effect on persistence duration in the specific-reading-disabled group than in the control group at 12 c/deg. Consequently, contrast had less effect on persistence in specific-reading-disabled children than in normal readers, especially at durations longer than the "critical duration" for each spatial frequency. Experiment 3 extended this finding to gratings with spatial frequencies of 4 and 8 c/deg. These results indicate a difference between normal and specific-reading-disabled children in cortical visible persistence. Two scores of visual processing were derived from the above experiments. On these scores the reading-disabled children were divided into Visual Disabled Readers (approximately 70%--eight subjects) and Nonvisual Disabled Readers (approximately 30%--four subjects). The percentages of disabled readers in each category remained constant when the sample size was increased to 61 normal and disabled readers.     

Group aggregates and individual reliability: The case of verbal short-term memory

Two experiments examined the generalizability of the effects of word length and phonological similarity with visual and auditory presentation in immediate verbal serial ordered recall. In Experiment 1, data were collected from 251 adult volunteers drawn from a broad cross-section of the normal population. Word length and phonological similarity in both presentation modes significantly influenced the group means. However, 43% of the subjects failed to show at least one of the effects, and the likelihood that effects appeared was highly correlated with verbal memory span. In Experiment 2, 40 subjects of the original sample were retested, 20 of whom had failed to show one or more effects in Experiment 1. Whether or not an effect had appeared for individual subjects on the first test session was a poor predictor of whether the effect would appear on retest. Finally, an analysis of subject reports demonstrated that the patterns of experimental data could be accounted for in part by the strategies that subjects reported using, and the effect of strategy was independent of the effect of span. The implications of these findings for theories of verbal short-term memory are discussed.     

Temporal learning in random control procedures

Experiments 1 and 2 delivered conditioned stimuli (CSs) at random times and unconditioned stimuli (USs) at either fixed (Experiment 1) or random (Experiment 2) intervals. In Experiment 3, CS duration was manipulated, and US deliveries occurred at random during the background. In all 3 experiments, the mean rate of responding (head entries into the food cup) in the background was determined by the mean US-US interval, and the mean rate during the CS was a linear combination of responding controlled by the mean US-US and mean CS onset-US intervals; the pattern of responding in time was determined by the interval distribution form (fixed or random). An event-based timing account, Packet theory, provided an explanation of the results.     

个体认知方式与材料复杂性对视空间工作记忆的影响

采用计算机呈现的Corsi积木点击任务,探讨了不同认知方式个体对材料的路径、结构和数量复杂性不同的视空间工作记忆的广度。研究结果表明：（1）场独立性认知方式是影响视空间工作记忆广度的一个重要的个别差异变量,在路径复杂或呈现的材料结构随机的条件下,场独立者的视空间工作记忆广度明显高于场依存者;（2）材料呈现的路径、数量是影响视空间记忆广度的重要因素,在路径简单或数量少的情况下被试的视空间记忆广度要明显得高     

外显、内隐记忆中不同认知方式个体的社会定向

以中文双字词为实验材料,分别从两个层面探讨场依存个体与场独立个体对社会词或非社会词的记忆有无偏向。实验一采用双任务,分散注意学习条件,实验二引入加工分离程序(PDP)。研究结果表明:(1)在双任务分散注意学习条件下,场依存个体对非目标社会词存在记忆偏向。(2)在内隐记忆成绩上,场依存个体对社会词存在记忆偏向,场独立个体对非社会词存在记忆偏向。     

Priming of face matching in amnesia.

Priming was studied in a task that required a speeded response to photographs of faces. On each trial, subjects viewed two faces and decided if the same person was shown twice or if two different people were shown. Both familiar and unfamiliar (i.e., well-known and unknown) faces were used, and some face pairs were repeated with a mean delay of about 10 min. Repetition was associated with faster reaction times in young subjects (Experiment 1) as well as in amnesic patients and age-matched control subjects (Experiment 2). The patients' reaction times were slower overall, although the magnitude of the priming effect did not differ from that in the control subjects. This preservation of a normal reaction-time facilitation in subjects with impaired recognition memory for faces occurred for both familiar and unfamiliar faces, suggesting that amnesia does not necessarily interfere with the acquisition of new information as indexed by this priming effect.     

Effects of short-term counseling on Career Maturity of tenth-grade students

The effectiveness of short-term counseling on Career Maturity of tenth-grade students as measured by the Career Maturity Inventory was studied. The Career Maturity Attitude Scale and the Self Appraisal subscale of the Competence Test were administered to a random sample (87 subjects) of tenth-grade students. The subjects whose scores fell below the mean were assigned randomly to experimental and control groups. The experimental group (17 subjects) received special counseling during a short term of 6 wk. Using repeated measures of analysis of variance, a statistically significant interaction was found with both the Self Appraisal subscale scores and the Total scale scores. Results indicate that career maturity as a developmental process can be measured and facilitated through counseling.     

Insight into the law of large numbers: A comparison of piagetian and judgement theory

Subjects were tested for their understanding of the law of large numbers in three ways: by means of a Piagetian task involving the distribution of balls between two compartments, by means of written tasks similar to those devised by Kahneman and Tversky (1972), and by means of a task involving comparisons of samples of counters drawn from a larger population. For the sample comparison task, subjects relied heavily on proportional information-ignoring sample size, thereby supporting the conclusions of Kahneman and Tversky (1972). However with regard to the other two tasks an order effect was found: subjects did significantly better with the Kahneman and Tversky tasks if they had first been tested on a Piagetian task. In Experiment II, the order effect was replicated, indicating that subjects may have a narrow insight into the law of large numbers which is not recruited in appropriate contexts unless primed by the task environment.     

Memory for lateral orientation of slides in picture stories

Three picture stories were constructed by taking slides of people involved in three different activities. Two sequences of these slides were presented. Subjects were asked whether or not each slide in the second sequence was in the same lateral orientation as in the first sequence. Experiment 1 presented the slides in correct or random sequence and in correct or random lateral orientation (2 by 2 design). The two groups who received correct orientation excelled in recognition of orientation in the test series. Experiment 2 replicated the random orientation condition, found that pre-warning of the recognition task had no effect on performance, and suggested that these subjects did not make use of the events in determining laterality. Experiment 3 replicated the correct order and orientation condition and further revealed that new but appropriate slides in the test series were accurately judged as to lateral orientation which fit the context of the original stories.     

Base-rate training without case cues reduces base-rate neglect

Base-rate neglect is a persistent phenomenon in which subjects do not place sufficient weight on the probabilities of occurrence of relevant events. Two experiments with college students support the hypothesis that base-rate neglect may be minimized by providing base-rate training in the absence of case, or witness, cues, prior to introducing (or reintroducing) these cues. In Experiment 1, the hypothesis was supported by both within-subjects and between-groups assessments; in Experiment 2, the hypothesis was supported while the effects of instructions and a correction procedure were found to be minimal. In Experiment 1, but not in Experiment 2, training with case cues present also reduced base-rate neglect, but this effect was not sufficient to account for the effect of cue-absent base-rate training. Correction trials led some subjects to detect that the task contingencies were random; however, neither this nor actually telling subjects after the experiment that the task was indeed random led invariably to subjects’ describing the optimal strategy (which was to choose the richer alternative exclusively).     

Construct validity of parent ratings of inhibitory control.

Recent literature has emphasized the need to examine executive functions (EF) in children using multiple sources, including both parent rating and performance-based measures. Computerized Go/No-Go tests, including commercially available continuous performance tests (CPTs), represent one of the most commonly used methods of assessing inhibitory control - a variable central to the executive function construct. We examined the relationship between parent ratings of inhibitory control and CPT performance in two mixed clinical samples. Experiment 1 examined 109 children ages 6-18 using the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000) and the Conners' CPT-II (Conners, 2000). In this sample, ratings on the BRIEF Inhibit scale (mean T-score = 62.3) were significantly higher than the CPT-II commissions score (mean T-score = 50.7; p < .0001); and the BRIEF and CPT-II scores were not highly correlated (r = - .12). Experiment 2 examined a sample of 131 children ages 7-18 using the BRIEF and the Tests of Variables of Attention (TOVA; Greenberg, 1996). In this sample, parent ratings on the BRIEF Inhibit scale (mean T-score = 56.8) were similar to TOVA commissions scores (mean T-score = 58.6; p = .33), although still poorly correlated (r = -.02). Factor analyses exploring covariance between BRIEF scales CPT-II variables (Experiment 1) and between BRIEF and TOVA (Experiment 2) yielded similar findings. In both experiments, all eight BRIEF scales loaded on a single factor, with no overlap with either the CPT-II or the TOVA. In mixed outpatient clinical samples, the BRIEF appears to measure different elements of inhibitory control than those assessed by computerized continuous performance tests.     

Construct Validity of Parent Ratings of Inhibitory Control

Recent literature has emphasized the need to examine executive functions (EF) in children using multiple sources, including both parent rating and performance-based measures. Computerized Go/No-Go tests, including commercially available continuous performance tests (CPTs), represent one of the most commonly used methods of assessing inhibitory control—a variable central to the executive function construct. We examined the relationship between parent ratings of inhibitory control and CPT performance in two mixed clinical samples. Experiment 1 examined 109 children ages 6–18 using the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000) and the Conners' CPT-II (Conners, 2000). In this sample, ratings on the BRIEF Inhibit scale (mean T-score?=?62.3) were significantly higher than the CPT-II commissions score (mean T-score?=?50.7; p < .0001); and the BRIEF and CPT-II scores were not highly correlated (r?=???.12). Experiment 2 examined a sample of 131 children ages 7–18 using the BRIEF and the Tests of Variables of Attention (TOVA; Greenberg, 1996). In this sample, parent ratings on the BRIEF Inhibit scale (mean T-score?=?56.8) were similar to TOVA commissions scores (mean T-score?=?58.6; p?=?.33), although still poorly correlated (r?=??.02). Factor analyses exploring covariance between BRIEF scales CPT-II variables (Experiment 1) and between BRIEF and TOVA (Experiment 2) yielded similar findings. In both experiments, all eight BRIEF scales loaded on a single factor, with no overlap with either the CPT-II or the TOVA. In mixed outpatient clinical samples, the BRIEF appears to measure different elements of inhibitory control than those assessed by computerized continuous performance tests.     

Effects of distance between objects and distance from the vertical axis on shape identity judgments

In three experiments, we independently manipulated the angular disparity between objects to be compared and the angular distance between the central axis of the objects and the vertical axis in a mental rotation paradigm. There was a linear increase in reaction times that was attributable to both factors. This result held whether the objects were rotated (with respect to each other and to the upright) within the frontal-parallel plane (Experiment 1) or in depth (Experiment 2), although the effects of both factors were greater for objects rotated in depth than for objects rotated within the frontal-parallel plane (Experiment 3). In addition, the factors interacted when the subjects had to search for matching ends of the figures (Experiments 1 and 2), but they were additive when the ends that matched were evident (Experiment 3). These data may be interpreted to mean that subjects normalize or reference an object with respect to the vertical upright as well as compute the rotational transformations used to determine shape identity.     

Audit responses: responses maintained by access to existing self or coactor scores during non-social, parallel work, and cooperation procedures

Human subjects, mostly between 11 and 16 yr old, matched to sample for points that were exchangeable for money. An audit response was defined as a response maintained by allowing a subject access to an existing score on his own (self audit) or a coactor's (coactor audit) performance. In Experiment I, changes from non-social procedures (no coactor) to social procedures (coactor present) increased self and coactor audits. Since both types of audits occurred at about the same rates during cooperation and parallel work procedures, the increases did not depend on the subjects' response interactions. Although Experiment I did not demonstrate that subjects were comparing scores, the frequent occurrence of each kind of audit within a brief time period (interpersonal audit) did indicate that it was reinforcing to have both scores at the same time. These interpersonal audits suggested that the coactor's score increased self audits during social procedures. Experiment II supported this notion: relative to a non-social procedure, self audits increased more during a parallel work procedure when the coactor's score was accessible than when it was not accessible. Thus, increases in other behaviors that occur in the presence of a coactor, i.e., social facilitation, may also result from or be increased by providing a coactor's score.