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1.
The advantages of presenting sensory data in terms of stimulus variables are stressed. Spectral sensitivity plots of local electroretinograms and ganglion cell discharges from the dark-adapted rabbit retina illustrate the utility of using this kind of procedure. Spectral data agreed with the literature demonstrating two cone and one rod process in this animal. The spectral sensitivities of both the local electroretinogram and ganglion cell spikes were closely similar. Data pertaining to pattern vision may also be subjected to the same type of analysis and described in terms of stimulus variables.  相似文献   

2.
The high-pressure induced phase transition in LaS has been investigated by means of first-principles calculations, and density-functional linear-response theory. A pressure-induced soft-acoustic phonon mode is identified at 30?GPa, which is in favourable agreement with the measured pressure-induced phase transition in LaS from the rocksalt to the CsCl structure. Phonon calculations reveal that pressure-induced instabilities of the transverse acoustic modes at the [?00] and [??0] directions are responsible for the phase transition. Furthermore, it is found that a decrease of bonding for S-p bonds and an increase of anti-bonding for La-d bonds significantly weakens the stability of the rocksalt phase of LaS under pressure, and hence inducing the structural phase transformation.  相似文献   

3.
基于计算机形式的测验使得收集作答反应时信息成为可能,这些信息的有效利用对心理与教育测验的理论研究和实际应用产生了重大影响。首先,归纳并总结了测验中使用反应时信息的五大优势。其次,分别介绍了4种不同取向下较典型的反应时模型与模型特征,并分别进行评价。再次,较系统地梳理了反应时模型在实践中的应用,使读者了解反应时信息在测验中所发挥的作用。最后,探讨了未来将反应时应用于心理与教育测量领域的几个研究方向。  相似文献   

4.
The item response function (IRF) for a polytomously scored item is defined as a weighted sum of the item category response functions (ICRF, the probability of getting a particular score for a randomly sampled examinee of ability ). This paper establishes the correspondence between an IRF and a unique set of ICRFs for two of the most commonly used polytomous IRT models (the partial credit models and the graded response model). Specifically, a proof of the following assertion is provided for these models: If two items have the same IRF, then they must have the same number of categories; moreover, they must consist of the same ICRFs. As a corollary, for the Rasch dichotomous model, if two tests have the same test characteristic function (TCF), then they must have the same number of items. Moreover, for each item in one of the tests, an item in the other test with an identical IRF must exist. Theoretical as well as practical implications of these results are discussed.This research was supported by Educational Testing Service Allocation Projects No. 79409 and No. 79413. The authors wish to thank John Donoghue, Ming-Mei Wang, Rebecca Zwick, and Zhiliang Ying for their useful comments and discussions. The authors also wish to thank three anonymous reviewers for their comments.  相似文献   

5.
In Experiment 1, autoshaping trials terminated with food only if pigeons emitted more than a target number of responses during a trial in one condition and fewer than a target number in another. The median number of responses per trial shifted in accordance wtih the requirements. The responding of yoked-control birds that received response-independent reinforcers did not vary with the response requirements. In Experiment 2, the number of responses in autoshaping trial became the discriminative stimulus for reinforcement in the second component of a chained schedule. In one condition, responding was reinforced only if the number of responses in the first component was above a target value; in the other condition, responding was reinforced only if the number was below the target value. The distribution of the first-component response numbers did not shift systematically between discrimination conditions, but response rates in the second component indicated that the number of responses in the autoshaping trial was a discriminable property behavior.  相似文献   

6.
The goal of this study was to examine the development of attention and response inhibition from ages 5 to 7. Forty children (20 5‐year‐olds and 20 7‐year‐olds) completed four counterbalanced phases of a continuous performance task. Phase 1 was designed to measure attention without distraction, Phase 2 was designed to measure attention with distraction, Phase 3 was designed to measure attention and response inhibition without distraction, and Phase 4 was designed to measure attention and response inhibition with distraction. With regard to attention, 7‐year‐olds performed significantly better than 5‐year‐olds. This age difference was more pronounced when distraction was present. With regard to response inhibition, there were no significant age differences. These results appear to suggest that attention improves between ages 5 and 7 but response inhibition does not. However, conclusions regarding response inhibition were limited because the distraction appeared to have had too powerful an effect on the 5‐year‐olds. Implications and future directions are discussed. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

7.
随着计算机测验使用的普及化,被试在心理与教育测验上的作答反应时的获取也越发便利。为了充分利用项目反应时信息,单维与多维的反应时模型相继被提出。然后,在项目间多维反应时数据中,潜在特质速度之间可能存在共同关系(比如,层阶关系),此时现有的反应时模型并不能适用。基于此,本研究提出了高阶对数正态反应时模型与双因子对数正态反应时模型。在模拟研究中,高阶对数正态反应时模型与双因子对数正态反应时模型的各参数都能被准确估计。在瑞文标准推理测验的三组测验项目的反应时数据中,双因子对数正态反应时模型表现出更为优秀的拟合效果,同时基于多个统计量说明了局部与全局潜在特质速度同时存在的必要性。因此,在项目间多维测验反应时数据分析中,非常有必要考虑多维潜在特质速度之间的共同效应。  相似文献   

8.
In recent years, item response tree (IRTree) approaches have received increasing attention in the response style literature for their ability to partial out response style latent variables as well as associated item parameters. When an IRTree approach is adopted to measure extreme response styles, directional and content invariance could be assumed at the latent variable and item parameter levels. In this study, we propose to evaluate the empirical validity of these invariance assumptions by employing a general IRTree model with relaxed invariance assumptions. This would allow us to examine extreme response biases, beyond extreme response styles. With three empirical applications of the proposed evaluation, we find that relaxing some of the invariance assumptions improves the model fit, which suggests that not all assumed invariances are empirically supported. Specifically, at the latent variable level, we find reasonable evidence for directional invariance but mixed evidence for content invariance, although we also find that estimated correlations between content-specific extreme response latent variables are high, hinting at the potential presence of a general extreme response tendency. At the item parameter level, we find no directional or content invariance for thresholds and no content invariance for slopes. We discuss how the variant item parameter estimates obtained from a general IRTree model can offer useful insight to help us understand response bias related to extreme responding measured within the IRTree framework.  相似文献   

9.
A duration-based preference assessment identified items that matched and did not match the sensory consequences hypothesized to maintain stereotypy. When evaluated in treatment, these items effectively competed with the occurrence of stereotypy, regardless of their sensory properties. It is suggested that relative preference, as measured in duration-based assessment, can be as significant as type of stimulation produced in interventions that reduce automatically reinforced problem behavior.  相似文献   

10.
Three experiments were conducted to evaluate response allocation of stereotypy during free-operant and restricted-operant conditions. Five children with autism or related developmental disabilities participated in at least one and up to three of the experiments. In Experiment 1, the stereotypic response that emerged as most probable during a free-operant phase was restricted, and response allocation was again evaluated. The results for 3 participants showed that restricting the high-probability response was correlated with covarying reductions in a nontargeted stereotypy. In Experiment 2, the effect of environmental enrichment on response allocation was evaluated. One participant reallocated behavior to appropriate object manipulation, 1 participant showed no change in behavior, and a 3rd participant reallocated behavior to object manipulation only when the putative stimulus products of the object manipulation matched those of stereotypy. In Experiment 3, additional interventions were implemented to promote response reallocation. Results showed that both response restriction and reinforcement for object manipulation decreased stereotypy and increased object manipulation. Collectively, the results of these experiments point to a need for complex evaluations of interventions for stereotypy.  相似文献   

11.
Two pigeons were required to peck six to nine illuminated response keys. A response on any one of the keys darkened that key. When each key had been darkened, a reinforcer was delivered. No specific sequence of key pecking was ever required. The keys were presented in various matrices: three by two, three by three, horizontal rows, and vertical columns. The keys either presented the same stimulus, white light; or each key presented a different stimulus, a color or form. The results indicated that although there were 720 to 362,880 different sequences that would produce reinforcement, each bird developed a particular, stereotyped sequence that dominated its behavior. Variability among the birds across phases yielded less than 60 sequences, .0001 to 6 percent of the possible sequences. The data suggest that a reinforcement contingency that includes “free choice” of response sequence will produce stereotypical response sequences that function as complex “units” of behavior.  相似文献   

12.
Amounts of crying were measured for two groups of infants in two states, calm and crying. The stimulus group was exposed to two test-cry stimuli (own-cry/other-cry) in both states. The control group was not exposed to the test-cry stimuli. For the stimulus group, results showed that there was no significant difference in the amount of crying during presentation of either the own-cry or other-cry test stimulus. However, the stimulus group did cry significantly less than the control group. This difference in the amount of crying was attributed to the capacity of the infant to suppress crying in the presence of auditory stimuli.  相似文献   

13.
In low-stakes assessments, test performance has few or no consequences for examinees themselves, so that examinees may not be fully engaged when answering the items. Instead of engaging in solution behaviour, disengaged examinees might randomly guess or generate no response at all. When ignored, examinee disengagement poses a severe threat to the validity of results obtained from low-stakes assessments. Statistical modelling approaches in educational measurement have been proposed that account for non-response or for guessing, but do not consider both types of disengaged behaviour simultaneously. We bring together research on modelling examinee engagement and research on missing values and present a hierarchical latent response model for identifying and modelling the processes associated with examinee disengagement jointly with the processes associated with engaged responses. To that end, we employ a mixture model that identifies disengagement at the item-by-examinee level by assuming different data-generating processes underlying item responses and omissions, respectively, as well as response times associated with engaged and disengaged behaviour. By modelling examinee engagement with a latent response framework, the model allows assessing how examinee engagement relates to ability and speed as well as to identify items that are likely to evoke disengaged test-taking behaviour. An illustration of the model by means of an application to real data is presented.  相似文献   

14.
Three methods for estimating reliability are studied within the context of nonparametric item response theory. Two were proposed originally by Mokken (1971) and a third is developed in this paper. Using a Monte Carlo strategy, these three estimation methods are compared with four classical lower bounds to reliability. Finally, recommendations are given concerning the use of these estimation methods.The authors are grateful for constructive comments from the reviewers and from Charles Lewis.  相似文献   

15.
Five experimentally naive albino rats were placed under a nondiscriminated lever-press avoidance schedule in which the delay to the next shock for responses after a shock was longer than the delay for responses after a response. Four rats acquired the postshock response pattern and maintained it for a prolonged period. The results revealed that postshock responding was under operant control and was not purely shock-elicited. It was suggested that the two kinds of response-shock interval, i.e. the shock-response-shock interval and the response-response-shock interval, could and should be independently controlled in nondiscriminated avoidance schedules.  相似文献   

16.
Response interruption and redirection (RIRD) is a common treatment for automatically reinforced vocal stereotypy; it involves the contingent presentation of task instructions. Tasks that are included in RIRD are typically selected based on caregiver report, which may affect the efficacy of RIRD. The purpose of the current study was to evaluate the role of task preference in the efficacy of RIRD for four participants who engaged in vocal stereotypy. We conducted task-preference assessments and selected tasks of varying preferences to include in RIRD. For three out of four participants, the results showed that RIRD with higher preference tasks was not effective at reducing vocal stereotypy, whereas RIRD with lower preference tasks was effective for all participants.  相似文献   

17.
苏波波  郑美红 《心理科学进展》2019,27(11):1863-1874
成瘾者失控的物质寻求和使用与反应抑制的关系密切。很多研究在物质相关线索情境中探讨了这一关系。物质相关线索既可受到自动的注意加工, 又可诱发非自动的趋近动机状态。因此, 它们可能通过刺激驱动和状态依赖两种方式消耗有限的认知资源从而影响反应抑制, 这在成瘾行为的发展和维持中起到重要作用。未来需要在揭示其神经机制、明确物质使用动机或态度的调节、采用真实情境进行研究, 以及开发有效的干预方法等几个方面开展研究。  相似文献   

18.
Recent research has shown that simple motor actions, such as pointing or grasping, can modulate the way we perceive and attend to our visual environment. Here we examine the role of action in spatial context learning. Previous studies using keyboard responses have revealed that people are faster locating a target on repeated visual search displays (“contextual cueing”). However, this learning appears to depend on the task and response requirements. In Experiment 1, participants searched for a T-target among L-distractors and responded either by pressing a key or by touching the screen. Comparable contextual cueing was found in both response modes. Moreover, learning transferred between keyboard and touch screen responses. Experiment 2 showed that learning occurred even for repeated displays that required no response, and this learning was as strong as learning for displays that required a response. Learning on no-response trials cannot be accounted for by oculomotor responses, as learning was observed when eye movements were discouraged (Experiment 3). We suggest that spatial context learning is abstracted from motor actions.  相似文献   

19.
Background and Objectives: Repressive coping has been associated with elevated cardiovascular reactivity and diminished self-reported negative affect (so-called autonomic-subjective response dissociation, ASRD) in response to laboratory stressors. However, there is a lack of knowledge regarding the ecological validity of this response pattern. Design: An ambulatory assessment strategy was applied in order to analyze associations between ASRD and repressive coping throughout a day. Methods: A sample of 114 individuals was recruited. Heart rate was recorded via ECG and subjective reports of negative affect as well as the experience of demand and control (as indicators of stress) and situational characteristics were assessed several times a day via mobile electronic devices. Results: Repressive coping relative to other coping dispositions was accompanied by elevated ASRD during stressful episodes in daily life, thus supporting previous laboratory research. Conclusions: The findings suggest that repressive coping is associated with a discrepancy between subjective reports of negative affect and autonomic responding to stressful encounters in everyday life, which might impact health.  相似文献   

20.
A new model, called acceleration model, is proposed in the framework of the heterogenous case of the graded response model, based on processing functions defined for a finite or enumerable number of steps. The model is expected to be useful in cognitive assessment, as well as in more traditional areas of application of latent trait models. Criteria for evaluating models are proposed, and soundness and robustness of the acceleration model are discussed. Graded response models based on individual choice behavior are also discussed, and criticisms on model selection in terms of fitnesses of models to the data are also given.This research was supported by the Office of Naval Research (N00014-90-J-1456).  相似文献   

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