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1.
Coren and Hakstian (1990) identified a serious methodological problem that arises in auditory research because of interaural correlation. When measures from both ears of the subjects are pooled together in an experimental design that assumes independence of measures, there can be spuriously high apparent statistical significance. The present paper provides further evidence in support of Coren and Hakstian's argument and also derives a formula that effectively corrects inflated test statistics resulting from interaural correlation. This formula is a special case of a more general one that applies in many other experimental contexts in which nonindependence of measures is a problem. We found that statistical tests based on our formula have somewhat greater power to detect differences than the kind of correction method advocated by Coren and Hakstian.  相似文献   

2.
Coren and Hakstian (1990) identified a serious methodological problem that arises in auditory research because of interaural correlation. When measures from both ears of the subjects are pooled together in an experimental design that assumes independence of measures, there can be spuriously high apparent statistical significance. The present paper provides further evidence in support of Coren and Hakstian’s argument and also derives a formula that effectively corrects inflated test statistics resulting from interaural correlation. This formula is a special case of a more general one that applies in many other experimental contexts in which nonindependence of measures is a problem. We found that statistical tests based on our formula have somewhat greater power to detect differences than the kind of correction method advocated by Coren and Hakstian.  相似文献   

3.
Coren (1989) noticed that the various air-conduction pure-tone thresholds obtained from one ear of an individual in quiet tend to display a high correlation. In addition, Coren and Hakstian (1990) reported a consistently high correlation between pure-tone thresholds in the two ears of the same individual. On the basis of these observations, these authors proposed that pure-tone thresholds measured at audiometric frequencies in one ear, and those measured in both ears of an individual, be collapsed into a single average threshold value. The present paper disputes the usefulness and the appropriateness of such a proposal.  相似文献   

4.
The short- and long-range apparent motion processes are discussed in terms of the statistical properties of images. It is argued that the short-range process, exemplified by the random-dot kinematogram, is primarily sensitive to the dipole statistics, whereas the long-range process, exemplified by illusory occlusion, is treated by the visual system primarily in terms of the tripole and higher statistical correlation functions. The studies incorporate the balanced dot, which is a unique stimulus element that permits high pass filtering while preserving detailed positional information. Low spatial frequencies are shown to be critical for texture segregation in random-dot kinematograms, independent of the grain size or number density of texture elements. Illusory path perception in the long-range process is shown not to require low spatial frequencies, but is sensitive rather to global temporal phase coherency. These results are interpreted in terms of the respective roles of the power and phase spectra in perceptual organization. The construction of balanced dots is discussed in detail.  相似文献   

5.
Previous work had shown that, when a memory-span experiment is performed with half the items presented to one ear, and half simultaneously to the other, a certain order of response appears. Either one ear or the other is dealt with first, and then the remaining items produce a response afterwards. The present results extend this finding to the eye and the ear rather than the two ears, and also to two voices distinguished by their frequency characteristics. For the latter condition, it is also shown that alternation of attention can take place at a speed faster than between the two ears. The effect thus appears to be a general one, and not merely a peculiarity of binaural hearing.  相似文献   

6.
Coupled data arise in perceptual research when subjects are contributing two scores to the data pool. These two scores, it can be reasonably argued, cannot be assumed to be independent of one another; therefore, special treatment is needed when performing statistical inference. This paper shows how the Type I error rate of randomization-based inference is affected by coupled data. It is demonstrated through Monte Carlo simulation that a randomization test behaves much like its parametric counterpart except that, for the randomization test, a negative correlation results in an inflation in the Type I error rate. A new randomization test, the couplet-referenced randomization test, is developed and shown to work for sample sizes of 8 or more observations. An example is presented to demonstrate the computation and interpretation of the new randomization test.  相似文献   

7.
Data in psychology are often collected using Likert‐type scales, and it has been shown that factor analysis of Likert‐type data is better performed on the polychoric correlation matrix than on the product‐moment covariance matrix, especially when the distributions of the observed variables are skewed. In theory, factor analysis of the polychoric correlation matrix is best conducted using generalized least squares with an asymptotically correct weight matrix (AGLS). However, simulation studies showed that both least squares (LS) and diagonally weighted least squares (DWLS) perform better than AGLS, and thus LS or DWLS is routinely used in practice. In either LS or DWLS, the associations among the polychoric correlation coefficients are completely ignored. To mend such a gap between statistical theory and empirical work, this paper proposes new methods, called ridge GLS, for factor analysis of ordinal data. Monte Carlo results show that, for a wide range of sample sizes, ridge GLS methods yield uniformly more accurate parameter estimates than existing methods (LS, DWLS, AGLS). A real‐data example indicates that estimates by ridge GLS are 9–20% more efficient than those by existing methods. Rescaled and adjusted test statistics as well as sandwich‐type standard errors following the ridge GLS methods also perform reasonably well.  相似文献   

8.
Mirman D  Magnuson JS  Estes KG  Dixon JA 《Cognition》2008,108(1):271-280
Many studies have shown that listeners can segment words from running speech based on conditional probabilities of syllable transitions, suggesting that this statistical learning could be a foundational component of language learning. However, few studies have shown a direct link between statistical segmentation and word learning. We examined this possible link in adults by following a statistical segmentation exposure phase with an artificial lexicon learning phase. Participants were able to learn all novel object-label pairings, but pairings were learned faster when labels contained high probability (word-like) or non-occurring syllable transitions from the statistical segmentation phase than when they contained low probability (boundary-straddling) syllable transitions. This suggests that, for adults, labels inconsistent with expectations based on statistical learning are harder to learn than consistent or neutral labels. In contrast, a previous study found that infants learn consistent labels, but not inconsistent or neutral labels.  相似文献   

9.
Binaural loudness matches in unilaterally impaired listeners   总被引:5,自引:0,他引:5  
Binaural loudness matching data using a 2IFC adaptive procedure were obtained in high-frequency, unilateral cochlear-impaired listeners. The matches were obtained at frequencies where both ears had similarly normal thresholds, and also at other frequencies where the impaired ear had various degrees of hearing loss. In these listeners, one presumed difference between the ears is the limited or altered spread of excitation in the impaired ear. In agreement with previous studies using other approaches (Hellman, 1974, 1978; Hellman & Meiselman, 1986; Moore, Glasberg, Hess & Birchall, 1985; Schneider & Parker, 1987), the results of the present study suggest that both the range and the slope of loudness growth function are not dependent on the spread of excitation, but instead are related primarily to the degree of threshold elevation at the test frequency. Following this suggestion, a spread-of-excitation-independent model, based upon a group of neurons with the same characteristic frequency (CF) but different thresholds, is proposed to account for loudness growth in both normal and recruitment cases. In particular, it is shown quantitatively that a compressed distribution of thresholds due to threshold elevation may be responsible for loudness recruitment in sensorineural hearing loss.  相似文献   

10.
质性研究中编码者信度的多种方法考察   总被引:1,自引:0,他引:1  
徐建平  张厚粲 《心理科学》2005,28(6):1430-1432
质性研究中检验编码者信度的方法有归类一致性指数、编码信度系数、相关系数、中位数检验、概化系数等。基于教师胜任力访谈数据集,对编码者信度考察结果表明,归类一致性指数和编码信度系数受相同编码数影响而不稳定,相关系数受数据类型制约,中位数检验受研究设计影响,概化系数则受编码者和编码项目的数量影响。研究中须合理选用。  相似文献   

11.
Statistical learning is characterized by detection of regularities in one's environment without an awareness or intention to learn, and it may play a critical role in language and social behavior. Accordingly, in this study we investigated the electrophysiological correlates of visual statistical learning in young children with autism spectrum disorder (ASD) using an event‐related potential shape learning paradigm, and we examined the relation between visual statistical learning and cognitive function. Compared to typically developing (TD) controls, the ASD group as a whole showed reduced evidence of learning as defined by N1 (early visual discrimination) and P300 (attention to novelty) components. Upon further analysis, in the ASD group there was a positive correlation between N1 amplitude difference and non‐verbal IQ, and a positive correlation between P300 amplitude difference and adaptive social function. Children with ASD and a high non‐verbal IQ and high adaptive social function demonstrated a distinctive pattern of learning. This is the first study to identify electrophysiological markers of visual statistical learning in children with ASD. Through this work we have demonstrated heterogeneity in statistical learning in ASD that maps onto non‐verbal cognition and adaptive social function.  相似文献   

12.
Previous research has shown that judgments of learning (JOLs) made immediately after encoding have a low correlation with actual cued-recall performance, whereas the correlation is high for delayed judgments. In this article, the authors propose a formal theory describing the stochastic drift of memory strength over the retention interval to account for the delayed-JOL effect. This is done by first decomposing the aggregated memory strength into exponential functions with slow and fast memory traces. The mean aggregated memory strength shows power-function forgetting curves. The drift of the memory strength is large for immediate JOLs (causing a low predictability) and weak for delayed JOLs (causing a high predictability). Consistent with empirical data, the model makes a novel prediction of JOL asymmetry, or that immediate weak JOLs are more predictive of future performance than are immediate strong JOLs. The JOL distributions for immediate and delayed JOLs are also accounted for.  相似文献   

13.
Many variables that are used in social and behavioural science research are ordinal categorical or polytomous variables. When more than one polytomous variable is involved in an analysis, observations are classified in a contingency table, and a commonly used statistic for describing the association between two variables is the polychoric correlation. This paper investigates the estimation of the polychoric correlation when the data set consists of misclassified observations. Two approaches for estimating the polychoric correlation have been developed. One assumes that the probabilities in relation to misclassification are known, and the other uses a double sampling scheme to obtain information on misclassification. A parameter estimation procedure is developed, and statistical properties for the estimates are discussed. The practicability and applicability of the proposed approaches are illustrated by analysing data sets that are based on real and generated data. Excel programmes with visual basic for application (VBA) have been developed to compute the estimate of the polychoric correlation and its standard error. The use of the structural equation modelling programme Mx to find parameter estimates in the double sampling scheme is discussed.  相似文献   

14.
The need for methods of clustering individuals into homogeneous groups seems clear. One hopes, by applying them to his data, to discover clusterings which may prove to be important. This aim appears straightforward, but the methods which exist do not necessarily satisfy them. The procedures which employ the correlation measure of profile similarity, and those which employ the distance measure are discussed. Technical and logical problems are shown to exist for both measures. The key defect in almost all clustering procedures seems to be the absence of a statistical model. The suggestion is made that the clustering problem be stated as a mixture problem. The need for further work by psychologists and statisticians is pointed out.  相似文献   

15.
In many situations, quantity estimates from multiple experts or diagnostic instruments must be collected and combined. Normatively, and all else equal, one should value information sources that are nonredundant, in the sense that correlation in forecast errors should be minimized. Past research on the preference for redundancy has been inconclusive. While some studies have suggested that people correctly place higher value on uncorrelated inputs when collecting estimates, others have shown that people either ignore correlation or, in some cases, even prefer it. The present experiments show that the preference for redundancy depends on one's intuitive theory of information. The most common intuitive theory identified is the Error Tradeoff Model (ETM), which explicitly distinguishes between measurement error and bias. According to ETM, measurement error can only be averaged out by consulting the same source multiple times (normatively false), and bias can only be averaged out by consulting different sources (normatively true). As a result, ETM leads people to prefer redundant estimates when the ratio of measurement error to bias is relatively high. Other participants favored different theories. Some adopted the normative model, while others were reluctant to mathematically average estimates from different sources in any circumstance. In a post hoc analysis, science majors were more likely than others to subscribe to the normative model. While tentative, this result lends insight into how intuitive theories might develop and also has potential ramifications for how statistical concepts such as correlation might best be learned and internalized.  相似文献   

16.
A topic of continuing interest in the measurement area is response acquiescence. A recent study has demonstrated the feasibiliy of studying acquiescence or, more importantly, content/acquiescence correlation in the MMPI. Utilizing the components of variance approach, this study found that the variance due to acquiescence in scores on the Pt and Hg scales was small relative to content variance, but that the correlation between acquiescence and content may be substantial for the Pt scale. The present paper describes a general statistical procedure for investigating content variance, variance due to non-content characteristics of items, and the covariances of content and various item characteristics. The data from a previous paper are reanalyzed, using alternative covariance structure models. Maximum likelihood procedures which allow for a statistical test for parameters of interest are used. The results point to the significance of the content- acquiescence correlation in the Pt scale, but not in the Hy scale. The previous findings are verified statistically, and procedures which hold promise for other investigation into the properties of behavioral tests are described.  相似文献   

17.
18.
Five dichotic speech experiments were conducted with normal adult listeners in which the signal to one or both ears was degraded by manipulation of intensity, signal-to-noise ratio, or bandwidth parameters. Results suggest that: (1) performance of the ear (or ears) receiving the degraded signal can be predicted from the monaural identifiability of the stimuli, and (2) dichotic performance, at least in stop consonant-vowel tests, reflects an additive central process which combines speech information from the two ears.  相似文献   

19.
Most research in statistical learning (SL) has focused on the mean success rates of participants in detecting statistical contingencies at a group level. In recent years, however, researchers have shown increased interest in individual abilities in SL, either to predict other cognitive capacities or as a tool for understanding the mechanism underlying SL. Most if not all of this research enterprise has employed SL tasks that were originally designed for group-level studies. We argue that from an individual difference perspective, such tasks are psychometrically weak, and sometimes even flawed. In particular, the existing SL tasks have three major shortcomings: (1) the number of trials in the test phase is often too small (or, there is extensive repetition of the same targets throughout the test); (2) a large proportion of the sample performs at chance level, so that most of the data points reflect noise; and (3) the test items following familiarization are all of the same type and an identical level of difficulty. These factors lead to high measurement error, inevitably resulting in low reliability, and thereby doubtful validity. Here we present a novel method specifically designed for the measurement of individual differences in visual SL. The novel task we offer displays substantially superior psychometric properties. We report data regarding the reliability of the task and discuss the importance of the implementation of such tasks in future research.  相似文献   

20.
Weber functions (ΔI/I in dB) for gated 250-Hz tones were studied for monaural and several binaural stimulus configurations (homophasic, and antiphasic with varying phase angle for addition of signal to masker). The various cues for discrimination of signal plus masker from masker alone are functions of intensity increments at one or both ears, an intensity increment at one ear coupled with a decrement at the other, or the introduction of a phase difference between the ears. The decline of the Weber fraction with increasing masker level (the “near miss” to Weber’s law) was confirmed for monaural discrimination over the entire 40-dB range, and a similar rate of decline was found for various binaural stimuli over the lower half of that range. The data also confirm the individual differences found in other studies for sensitivity favoring either interaural amplitude or interaural phase shifts.  相似文献   

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