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1.
The data obtained from one‐way independent groups designs is typically non‐normal in form and rarely equally variable across treatment populations (i.e. population variances are heterogeneous). Consequently, the classical test statistic that is used to assess statistical significance (i.e. the analysis of variance F test) typically provides invalid results (e.g. too many Type I errors, reduced power). For this reason, there has been considerable interest in finding a test statistic that is appropriate under conditions of non‐normality and variance heterogeneity. Previously recommended procedures for analysing such data include the James test, the Welch test applied either to the usual least squares estimators of central tendency and variability, or the Welch test with robust estimators (i.e. trimmed means and Winsorized variances). A new statistic proposed by Krishnamoorthy, Lu, and Mathew, intended to deal with heterogeneous variances, though not non‐normality, uses a parametric bootstrap procedure. In their investigation of the parametric bootstrap test, the authors examined its operating characteristics under limited conditions and did not compare it to the Welch test based on robust estimators. Thus, we investigated how the parametric bootstrap procedure and a modified parametric bootstrap procedure based on trimmed means perform relative to previously recommended procedures when data are non‐normal and heterogeneous. The results indicated that the tests based on trimmed means offer the best Type I error control and power when variances are unequal and at least some of the distribution shapes are non‐normal.  相似文献   

2.
This article proposes the image intraclass correlation (I2C2) coefficient as a global measure of reliability for imaging studies. The I2C2 generalizes the classic intraclass correlation (ICC) coefficient to the case when the data of interest are images, thereby providing a measure that is both intuitive and convenient. Drawing a connection with classical measurement error models for replication experiments, the I2C2 can be computed quickly, even in high-dimensional imaging studies. A nonparametric bootstrap procedure is introduced to quantify the variability of the I2C2 estimator. Furthermore, a Monte Carlo permutation is utilized to test reproducibility versus a zero I2C2, representing complete lack of reproducibility. Methodologies are applied to three replication studies arising from different brain imaging modalities and settings: regional analysis of volumes in normalized space imaging for characterizing brain morphology, seed-voxel brain activation maps based on resting-state functional magnetic resonance imaging (fMRI), and fractional anisotropy in an area surrounding the corpus callosum via diffusion tensor imaging. Notably, resting-state fMRI brain activation maps are found to have low reliability, ranging from .2 to .4. Software and data are available to provide easy access to the proposed methods.  相似文献   

3.
We study several aspects of bootstrap inference for covariance structure models based on three test statistics, including Type I error, power and sample‐size determination. Specifically, we discuss conditions for a test statistic to achieve a more accurate level of Type I error, both in theory and in practice. Details on power analysis and sample‐size determination are given. For data sets with heavy tails, we propose applying a bootstrap methodology to a transformed sample by a downweighting procedure. One of the key conditions for safe bootstrap inference is generally satisfied by the transformed sample but may not be satisfied by the original sample with heavy tails. Several data sets illustrate that, by combining downweighting and bootstrapping, a researcher may find a nearly optimal procedure for evaluating various aspects of covariance structure models. A rule for handling non‐convergence problems in bootstrap replications is proposed.  相似文献   

4.
《Visual cognition》2013,21(2):157-199
Scene recognition across a perspective change typically exhibits viewpoint dependence. Accordingly, the more the orientation of the test viewpoint departs from that of the study viewpoint, the more time its takes and the less accurate observers are to recognize the spatial layout. Three experiments show that observers can take advantage of a virtual avatar that specifies their future “embodied” perspective on the visual scene. This “out-of-body” priming reduces or even abolishes viewpoint dependence for detecting a change in an object location when the environment is respectively unknown or familiar to the observer. Viewpoint dependence occurs when both the priming and primed viewpoints do not match. Changes to permanent extended structures (such as walls) or altered object-to-object spatial relations across viewpoint change are detrimental to viewpoint priming. A neurocognitive model describes the coordination of “out-of-body” and “embodied” perspectives relevant to social perception when understanding what another individual sees.  相似文献   

5.
Georg Northoff 《Axiomathes》2016,26(3):253-277
While neuroscience has made enormous progress in understanding the brain, the implications of these empirical findings for ontological questions in philosophy including the mind–body problem remain yet unclear. In the first paper, I discussed the model of brain that as implied and supported by the empirical data. This leads me now to the question of an empirically plausible ontology of brain. Therefore, the aim in this second paper is the ontological characterization of the brain in terms of a process-based ontology that avoids what Whitehead described as “simple location” and “fallacy of misplaced concreteness”. The discussion of the model of the brain is complemented by developing a process-based ontological characterization of the brain. Specifically, as based on Whitehead, I argue that “simple location” of the brain as thing or object in time and space amounts to nothing but an abstraction rendering what Whitehead described as “fallacy of misplaced concreteness”. Instead of describing the brain as static, non-temporal and isolated thing or object, I characterize the brain ontologically by dynamic, temporal, and relational processes. This leads me to a process-based ontology of brain which may be specified in spatiotemporal terms. Since the world’s larger spatiotemporal range or scale contains, e.g., nests, the smaller one of the brain, I characterize their ontological relationship by “spatiotemporal nestedness” and “spatiotemporal directedness”. Such spatiotemporal relationship between world and brain precludes the confusion between the world as whole and the brain as part, e.g., “mereological confusion”. I conclude that process-based or better, more specifically, spatiotemporal ontology of the brain and its relationship to the world may offer novel views on the question for the ontological relationship between mind and brain, e.g., the mind–brain problem, by converting or reformulating it as “world-brain problem”.  相似文献   

6.
This commentary reflects on the different innovative motifs introduced into psychosocial research by the contributions to this special issue: the risk of oversubjectification in research placing undue emphasis on the individual reasoning or feeling subject, the attempt to link the “feelings” and “talk” about emotion in one interpretative framework, the place of the interview in research which questions rather than reinforces “identity,” the location of subjects in a “place-assemblage” rather than in their own selves, and the reconfiguration of “mindfulness” so that it opens out to social relations rather than evades them. Focussing on the role of psychoanalysis in psychosocial research, I situate these motifs within the analysis of the machinery of “facialization” offered by Deleuze and Guattari, in which the “white wall” of signification is complemented and locked in place by the “black hole” of subjectivity.  相似文献   

7.
Organic brain syndromes are of forensic interest for several reasons. First, patients with organic brain syndromes may require judicial determination of competence in any of a number of areas, e.g., testamentary capacity, need for financial guardianship, or competence to make medical decisions. Second, any patient whose mental state is of legal interest will need evaluation for contributing organic factors; uncovering these factors may have considerable medical and legal consequence. Third, the discovery of organic factors may be decisive in the outcome of a judicial proceeding, where “hard” biological data are often accorded more weight, and are thus more persuasive, than “soft” psychological data. This article provides an introductory overview of the organic brain syndromes. For each syndrome, the clinical features are described and are illustrated with a case vignette, the more common etiologies are presented, and selected aspects to the evaluation are highlighted. In addition, since the detectian of malingered mental illness is a key component in many forensic contexts, characteristics are described which help to distinguish actual from malingered mental illness.  相似文献   

8.
Obedience by male and female subjects to male and female experimenters was investigated under various conditions of “perceived legitimacy.” The procedure involved an experimenter stopping a subject who was about to cross a street at a particular crosswalk, the subject was then instructed to cross at another designated location. The dependent variable was the level of obedience to these instructions. The four main factorial independent variables were the sex of the experimenter, the sex of the subject, and two conditions of “perceived legitimacy” (presence or absence of a “uniform,” presence or absence of an “explanation”). Significant results were obtained for the uniform and sex of subject main effects (more obedience with a uniform, more disobedience by females). Additional analyses indicated that “older” subjects disobeyed more often than “younger” ones, that “formally” dressed subjects disobeyed more often than “informally” dressed ones, and that ethnic minority group experimenters were disobeyed significantly more often than Caucasian experimenters. Significant interactions were also obtained, mainly due to the behavior of the younger men and the older women. Male and female experimenters were obeyed equally, in general. The results are discussed in relation to sex-role prejudice and discriminatory behavior.  相似文献   

9.
This methodological article proposes a framework for analysing the relationship between cognitive processes and brain activity using variables measured by neurofeedback (NF) carried out by functional Magnetic Resonance Imagery (fMRI NF). Cognitive processes and brain activity variables can be analysed as either the dependant variable or the independent variable. Firstly, we propose two traditional approaches, defined in the article as the “neuropsychological” approach (NP) and the “psychophysiology” approach (PP), to extract dependent and independent variables in NF protocols. Secondly, we suggest that NF can be inspired by the style of inquiry used in neurophenomenology. fMRI NF allows participants to experiment with his or her own cognitive processes and their effects on brain region of interest (ROI) activations simultaneously. Thus, we suggest that fMRI NF could be improved by implementing “the elicitation interview method”, which allows the investigator to gather relevant verbatim from participants’ introspection on subjective experiences.  相似文献   

10.
The three wishes of a random sample of 100 subjects were obtained from each of five age groups: elementary, junior high, high school, early college (18–24 years), and late college (25–50 years). The wishes were placed in appropriate categories and into subcategories including possessions, activities, maintenance, achievement, and altruism. Exploratory measures of “confidence” and “sense of personal control” were taken for each subject. Sex and socioeconomic condition were analyzed. Results supported previously established trends of increasing generality, increasing altruism, and decreasing materialistic content up to different ages in adolescence and early adulthood depending on the data chosen to relate to the generalizations. In addition, a gradual increase in achievement wishes through middle adulthood was observed. The measure of “sense of personal control” was found to yield significant variation, while the data related to “confidence” varied only within chance limits. Comparisons with previous studies led to speculation that achievement orientations of adolescents may have lessened over the past decade.  相似文献   

11.
This paper presents a PC-based eye-position data collection and analysis system. Software routines are described that supplement hardware calibration procedures, improving data-collection accuracy and reducing the number of unusable trials. Collected eye-position data can be remapped over a displayed stimulus image and spatially and temporally represented by parameters such as individual fixations, clusters of fixations (Nodine, Carmody, & Kundel, 1978), cumulative clusters, and gaze durations. An important feature of the system is that the software routines preserve scan-path information that provides a sequential dimension to the analysis of eye-position data. A “hotspot” analysis is also described, which cumulates, across 1 or more observers, the frequency of eye-position landings or “hits” on designated areas of interest for a given stimulus. Experimental applications in the fields of radiology, psychology, and art are provided, illustrating how eye-position data can be interpreted both in signal detection and in information-processing frameworks using the present methods of analysis.  相似文献   

12.
For the Poggendorff display (transversal interrupted by parallel lines), the typical distance-misperception theory postulates that a particular linear distance extending across the empty space between parallels is underestimated; examples are the intertransversal slant distance defined by the closest ends of the transversal segments (a “wings-in Müller-Lyer like” underestimation) or the perpendicular distance between parallels (parallels “attract”). Distance misperception by itself, however, can neither establish that perceived transversal misalignment exists for a Poggendorff display nor specify the perceivedlocation conditions) that will produce perceptual collinearity. The perceptual displacement vector is introduced as a means of specifying fully the perceptual mislocation (displacement) of one transversal segment with respect to the other. Given this vector information (direction as well as distance), the logical soundness of theories postulating distance or location misperception were evaluated, and they were compared on the basis of extant data. Such vector information can be used to evaluate other classes of theories as well.  相似文献   

13.
Frequently finding a visual search target in one region of space induces a spatial attentional bias toward that region. Past studies on this effect typically tested fewer than 20 participants. The small sample prevents an investigation of two properties of learning: visual field uniformity and role of explicit awareness. Pooling data from multiple studies, here we examined location probability learning from ~120,000 visual search trials across 420 participants. Participants performed a serial search task. Unbeknownst to them, the target was disproportionately likely to appear in one visual quadrant. Location probability learning (LPL) was measured as the difference in reaction time to targets in the high-probability “rich” quadrant and the low-probability “sparse” quadrants. Results showed a lack of visual field effect. LPL was equivalent for “rich” quadrant in the upper left, upper right, lower left, and lower right. Learning did not induce a hotspot diagonal to the “rich” quadrant. To the contrary, RT was the longest in the diagonal quadrant. Recognition rate of the “rich” quadrant was above chance. However, recognition accuracy was unrelated to the size of LPL. Implicit learning induces visual-field-independent changes in spatial attention.  相似文献   

14.
A group of counselors met in seminar over a period of a year, critiquing tapes of their group counseling sessions. It was found through analysis of these recordings that certain themes could be identified which occurred and reoccurred in the content of group counseling with adolescents. These themes were entitled: “My Vices,” “Outwitting the Adults,” “Problem Parents,” “My Brother, the Brat,” “My Public Image,” “Nobody Loves Me,” and “Let's Change the Rules.” Illustrative material is presented that was transcribed from the recordings, after all identifying data were removed.  相似文献   

15.
探究不同心智活动下的神经表征差异, 是认知神经科学关注的核心问题之一。早期的脑电/脑磁分析方法主要关注组平均后的神经响应水平, 这要求在关注的时间进程上, 各个被试在相同刺激条件下事件相关电位/事件相关磁场的振幅大小和方向、以及地形图分布和极性均要有较高的一致性。近些年来, 研究者们将功能性磁共振成像研究中常用到的两种技术——机器学习中的分类算法(即基于分类的解码)和表征相似性分析——引入到了脑电/脑磁数据分析中。这两种新技术可以克服传统脑电/脑磁数据基于具体电压/磁感应强度波形平均分析的缺点, 具有在个体水平上探究神经表征编码的特点, 为人们探究大脑在不同时间进程上如何对特定的神经表征信息进行动态编码提供了新的思路。两种技术基于不同的方法学原理来抽提个体间一致的脑认知加工机制, 还为脑电/脑磁研究开展跨时域、跨任务、跨模态、跨群体比较不同认知过程中的表征差异提供了更多新颖的途径。我们首先通过与传统的脑电/脑磁分析方法进行比较, 系统性介绍了基于分类的解码和表征相似性分析的原理和操作流程, 之后对两种方法的应用场景进行了梳理, 并在最后对未来可供研究的方向提出了我们的见解。  相似文献   

16.
To develop a scoring scale to differentiate “behaving” from “misbehaving” children, sentence completion responses of 96 children whose classroom behavior was socially approved were compared with responses of 96 children whose behavior was disapproved because they were aggressive and disruptive. Applied to a cross-validation sample of 96 approved and 96 disapproved children, it was found that scoring reliability was satisfactory, that the total scale score could be used to discriminate between these groups, and that inspection of individual protocols might yield valuable insights concerning a child's personal problems.  相似文献   

17.
Two experiments are reported in which subjects compared the shape of two successively presented random visual forms. The first stimulus in the pair was one of five “standard” shapes, and the second stimulus was either the same as the standard or different by virtue of a perturbation in shape or an overall reflection. Marked individual differences were found in reaction time for the same-different comparison. For one type of subject “same” responses were faster than “different” responses, speed of “different” responses was unaffected by similarity of the test shape to the standard, and error rates and reaction times were not systematically related. For the other type of subject, “different” responses were generally faster than “same” responses, “different” reaction time decreased as the standard shape and the test shape became increasingly dissimilar, and error rates and reaction times were positively correlated. Implications of these individual differences for models of the same-different comparison process are discussed.  相似文献   

18.
Rape is often considered a crime and, as such. is subject to punishment. This paper reports a test of a “deterence theory” of rape with a cross-cultural study which uses a sample of societies drawn from the Human Relations Area Files. Fraternal interest group theory is also tested. This theory argues that the presence of fraternal interest groups, power groups of related males, predicts the occurrence of rape in a society. Although the results support both theories, a composite theory, using both deterrence and fraternal interest group theories, was found to provide a better explanation for the occurrence of rape than either theory alone.  相似文献   

19.
Motion sensor devices such as actigraphs are increasingly used in studies that seek to obtain an objective assessment of activity level. They have many advantages, and are useful additions to research in fields such as sleep assessment, drug efficacy, behavior genetics, and obesity. However, questions still remain over the reliability of data collected using actigraphic assessment. We aimed to apply generalizability theory to actigraph data collected on a large, general-population sample in middle childhood, during 8 cognitive tasks across two body loci, and to examine reliability coefficients on actigraph data aggregated across different numbers of tasks and different numbers of attachment loci. Our analyses show that aggregation greatly increases actigraph data reliability, with reliability coefficients on data collected at one body locus during 1 task (.29) being much lower than that aggregated across data collected on two body loci and during 8 tasks (.66). Further increases in reliability coefficients by aggregating across four loci and 12 tasks were estimated to be modest in prospective analyses, indicating an optimum trade-off between data collection and reliability estimates. We also examined possible instrumental effects on actigraph data and found these to be nonsignificant, further supporting the reliability and validity of actigraph data as a method of activity level assessment.  相似文献   

20.
Cognitive neuroimaging studies of individual differences seek to reveal brain mechanisms of cognition by associating intersubject variability in brain activation with other variables of interest, such as sex, personality trait, or mood state. The choice of a priori regions of interest (ROIs) raises problems, because the selection criterion is typically consistent activation across prior studies, suggesting little intersubject variability. Here, we introduce a novel approach for selecting regions that are defined on the basis of their variance characteristics, rather than on the basis of their location or because of theoretical expectations. These regions of variance (ROVs) constitute the search space with which to assess how much of the observed variance can be ascribed to specific variables of interest. We compare the ROI and ROV approaches by applying each to the same data set and suggest that the conjunction of both methods may yield the greatest likelihood of capturing the rich relation between brain and behavior, while limiting the search space for statistical analyses and minimizing false positive errors.  相似文献   

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