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1.
《Ethics & behavior》2013,23(2):69-86
The sharing of research data is now mandated by some funders to encourage openness and integrity in science, to ensure efficient use of research funds, and to provide training resources. Although data sharing has a long history in some parts of science, the full range of possibilities and challenges it offers are only now becoming apparent in the social sciences. This article (a) examines what may be entailed in sharing documented data, (b) provides a historical perspective on data sharing, (c) describes some of the creative and successful data-sharing relationships that have occurred in the social sciences, and (d) discusses some of the main concerns of social scientists with respect to sharing their data and how these concerns might be resolved.  相似文献   

2.
A program is described for principal component analysis with external information on subjects and variables. This method is calledconstrained principal component analysis (CPCA), in which regression analysis and principal component analysis are combined into a unified framework that allows a full exploration of data structures both within and outside known information on subjects and variables. Many existing methods are special cases of CPCA, and the program can be used for multivariate multiple regression, redundancy analysis, double redundancy analysis, dual scaling with external criteria, vector preference models, and GMANOVA (growth curve models).  相似文献   

3.
Biobanks are collections of human biological tissue specimens and related health data. Biobank research hopes to provide novel insights into the genetic component of disease, ultimately leading to a more personalized approach to healthcare. However, biobanks have sparked debate due to the ethical, legal, and social implications surrounding utilization of population samples and data. These controversies include issues of consent, privacy and confidentiality, return of results and data-sharing. This paper provides an overview of the different types and scope of biobanks and an examination of the most pertinent ethical, legal and social considerations surrounding such research, as well as how some of these concerns are being addressed. The paper finishes with a discussion of the relevance of biobanks to the genetic counseling field and concludes that genetic counselors are in a position to make a unique, educated and practical contribution to the ongoing dialogue and direction of biobank research.  相似文献   

4.
Earlier research has shown that bootstrap confidence intervals from principal component loadings give a good coverage of the population loadings. However, this only applies to complete data. When data are incomplete, missing data have to be handled before analysing the data. Multiple imputation may be used for this purpose. The question is how bootstrap confidence intervals for principal component loadings should be corrected for multiply imputed data. In this paper, several solutions are proposed. Simulations show that the proposed corrections for multiply imputed data give a good coverage of the population loadings in various situations.  相似文献   

5.
In many human movement studies angle-time series data on several groups of individuals are measured. Current methods to compare groups include comparisons of the mean value in each group or use multivariate techniques such as principal components analysis and perform tests on the principal component scores. Such methods have been useful, though discard a large amount of information. Functional data analysis (FDA) is an emerging statistical analysis technique in human movement research which treats the angle-time series data as a function rather than a series of discrete measurements. This approach retains all of the information in the data. Functional principal components analysis (FPCA) is an extension of multivariate principal components analysis which examines the variability of a sample of curves and has been used to examine differences in movement patterns of several groups of individuals. Currently the functional principal components (FPCs) for each group are either determined separately (yielding components that are group-specific), or by combining the data for all groups and determining the FPCs of the combined data (yielding components that summarize the entire data set). The group-specific FPCs contain both within and between group variation and issues arise when comparing FPCs across groups when the order of the FPCs alter in each group. The FPCs of the combined data may not adequately describe all groups of individuals and comparisons between groups typically use t-tests of the mean FPC scores in each group. When these differences are statistically non-significant it can be difficult to determine how a particular intervention is affecting movement patterns or how injured subjects differ from controls. In this paper we aim to perform FPCA in a manner allowing sensible comparisons between groups of curves. A statistical technique called common functional principal components analysis (CFPCA) is implemented. CFPCA identifies the common sources of variation evident across groups but allows the order of each component to change for a particular group. This allows for the direct comparison of components across groups. We use our method to analyze a biomechanical data set examining the mechanisms of chronic Achilles tendon injury and the functional effects of orthoses.  相似文献   

6.
Contour information generated by moving retinal images has been shown by others to be the principal determinant of perceived color. The data presented here show that, for brightness, this information reflects only differences between adjacent stimulus areas. The entire distribution of difference information from contours in the visual field must be specified in order to predict the brightness at any point.  相似文献   

7.
Much recent political psychology scholarship has examined the role of anxiety in vote choice. This work generally argues that anxiety affects vote choice indirectly by causing citizens to more thoroughly search for and process political information. This indirect effect of anxiety leads citizens to rely less on heuristics, such as party, and more on substantive information, such as policy positions. The most prominent example of this scholarship is the Affective Intelligence (AI) theory of emotions. In this paper, we use cross-sectional and panel survey data to test AI against two simpler alternatives: (1) that emotions directly influence candidate evaluations and (2) that candidate evaluations directly influence emotions. We first show that these simpler alternatives can produce the complex, cross-sectional interactions that provide the principal support for AI. Then, using panel data to better assess causal direction, we find little support for AI, some evidence that emotions directly influence candidate evaluations, and strong evidence that candidate evaluations directly influence emotions. Scholars, we conclude, should be hesitant to abandon these simpler explanations in favor of AI.  相似文献   

8.
Principal components analysis of sampled functions   总被引:3,自引:0,他引:3  
This paper describes a technique for principal components analysis of data consisting ofn functions each observed atp argument values. This problem arises particularly in the analysis of longitudinal data in which some behavior of a number of subjects is measured at a number of points in time. In such cases information about the behavior of one or more derivatives of the function being sampled can often be very useful, as for example in the analysis of growth or learning curves. It is shown that the use of derivative information is equivalent to a change of metric for the row space in classical principal components analysis. The reproducing kernel for the Hilbert space of functions plays a central role, and defines the best interpolating functions, which are generalized spline functions. An example is offered of how sensitivity to derivative information can reveal interesting aspects of the data.This research was supported by Grant PA 0320 to the second author by the Natural Sciences and Research Council of Canada. We are grateful to the reviewers of an earlier version and to J. B. Kruskal and S. Winsberg for many helpful comments concerning exposition.  相似文献   

9.
Quite recently, Luciano Floridi has put forward the fascinating suggestion that knowledge should be analyzed as special kind of information, in particular as accounted information. As I will try tentatively to show, one important consequence of Floridi’s proposal is that the notion of justification, and of evidence, should play no role in a philosophical understanding of knowledge. In this paper, I shall suggest one potential difficulty with which Floridi’s proposal might be consequently afflicted, yet accept the fundamental suggestion that traditional epistemology should be merrily wedded with the philosophy of information; in particular, I shall plead for the less drastic conclusion, according to which, although knowledge should be taken to entail justification, it is the very notion of evidence—in particular of perceptual evidence—that should be analyzed in information-theoretic terms. By so doing, my principal aim will be to explain away an apparent difficulty—which is preliminary to the preoccupations motivating Floridi’s more ambitious attempt—from which Conee and Feldman’s Evidentialism is apparently afflicted. So, the conclusion that I will try to establish is that the notion of perceptual evidence, once it is appropriately analyzed in information-theoretic terms, should play an important role in our understanding of knowledge.  相似文献   

10.
An experimental study was conducted to demonstrate the value of a procedure for analyzing motor performance data. A sample of 156 subjects practiced on two instruments for motor learning while arousal data were recorded. Each set of data was submitted to an analysis of principal components and four components resulted for each set of data. Similarity coefficients were calculated for pairs of component matrices after rotation to maximum similarity. The similarity coefficients exhibit a consistent pattern which provides meaningful information concerning influence of experimental conditions on performance data.  相似文献   

11.
Several hierarchical classes models can be considered for the modeling of three-way three-mode binary data, including the INDCLAS model (Leenen, Van Mechelen, De Boeck, and Rosenberg, 1999), the Tucker3-HICLAS model (Ceulemans, Van Mechelen, and Leenen, 2003), the Tucker2-HICLAS model (Ceulemans and Van Mechelen, 2004), and the Tucker1-HICLAS model that is introduced in this paper. Two questions then may be raised: (1) how are these models interrelated, and (2) given a specific data set, which of these models should be selected, and in which rank? In the present paper, we deal with these questions by (1) showing that the distinct hierarchical classes models for three-way three-mode binary data can be organized into a partially ordered hierarchy, and (2) by presenting model selection strategies based on extensions of the well-known scree test and on the Akaike information criterion. The latter strategies are evaluated by means of an extensive simulation study and are illustrated with an application to interpersonal emotion data. Finally, the presented hierarchy and model selection strategies are related to corresponding work by Kiers (1991) for principal component models for three-way three-mode real-valued data.  相似文献   

12.
To monopolize the scientific data gained by Japanese physicians and researchers from vivisections and other barbarous experiments performed on living humans in biological warfare programs such as Unit 731, immediately after the war the United States (US) government secretly granted those involved immunity from war crimes prosecution, withdrew vital information from the International Military Tribunal for the Far East, and publicly denounced otherwise irrefutable evidence from other sources such as the Russian Khabarovsk trial. Acting in "the national interest" and for the security of the US, authorities in the US tramped justice and morality, and engaged in what the English common law tradition clearly defines as "complicity after the fact." To repair this historical injustice, the US government should issue an official apology and offer appropriate compensation for having covered up Japanese medical war crimes for six decades. To help prevent similar acts of aiding principal offender(s) in the future, international declarations or codes of human rights and medical ethics should include a clause banning any kind of complicity in any unethical medicine-whether before or after the fact-by any state or group for whatever reasons.  相似文献   

13.
Human participants were trained to navigate to two geometrically equivalent corners of a parallelogram-shaped virtual environment. The unique shape of the environment combined three distinct types of geometric information that could be used in combination or in isolation to orient and locate the goals: the angular amplitudes of the corners, the relative wall length relationships, and the principal axis of symmetry. In testing, participants were placed in manipulated versions of the training environment that tested which types of geometry they had encoded and how angular information weighed in against the other two geometric properties. The test environments were (a) a rectangular environment that removed the angular information, (b) a rhombic environment that removed wall length information and drastically reduced the principal axis, and (c) a reverse-parallelogram-shaped environment that placed angular information against both wall length and principal axis information. Participants chose accurately in the rectangular and rhombus environments, despite the removal of one of the cues. In the conflict test, participants preferred corners with the correct angular amplitudes over corners that were correct according to both wall length relationships and the principal axis. These results are comparable to recent findings with pigeons and suggest that angles are a salient orientation cue for humans.  相似文献   

14.
The use of principal components analysis (PCA) for the study of evoked-response data may be complicated by variations from one trial to another in the latency of underlying brain events. Such variation can come from either random intra-and intersubject variability or from the effects of independent variables that are manipulated between conditions. The effect of such variability is investigated by simulation of these latency-varying events and by analysis of evoked responses in a behavioral task, the Sternberg memory search task, which is well known to generate variation in the latency of brain events. The results of PCA of within-subjects differences in these two situations are plausibly related to underlying stages of information processing, and the technique may augment reaction time data by providing information on the time of occurrence as well as the duration of stages of information processing.  相似文献   

15.
Abstract

The information available about face identity from the firing rate and from temporal encoding in the spike train of single neurons recorded in the temporal lobe visual cortical areas of rhesus macaques was analysed using principal component and information theory analyses of smoothed spike trains. The neurons analysed had responses selective for faces. The stimulus set consisted of 20 different faces. The first principal component provided by a considerable extent the most information (57%) available in principal components 1–5, with the second adding 18%, the third 16%, and the fourth and fifth adding 9%. For each image, the weighting on the first principal component was highly correlated with the mean firing rate of the neuron to that image. The information available from the firing rate of the neuron was very close to that available in the first principal component. Information theory analysis showed that in short epochs (e.g. 50 msec) the information available from the firing rate can be as high, on average, as 65% of that available from the firing rate calculated over 400 msec, and 38% of that available from principal components 1–3 in the 400-msec period. It was also found that 30% of the information calculated from the first three principal components is available in the firing rates calculated over epochs as short as 20 msec. More information was available near the start of the neuronal response, and the information available from short epochs became less later in the neuronal response. Taken together, these analyses provide evidence that a short period of firing taken close to the start of the neuronal response provides a reasonable proportion of the total information that would be available if a long period of neuronal firing (e.g. 400 msec) were utilized to extract it, even if temporal encoding were used. The implications of these and related findings are that at least for rapid object recognition, each cortical stage provides information to the next in a short period of 20–50 msec, does not rely on temporal encoding, and completes sufficient computation to provide an output to the next stage in this same 20- to 50-msec period.  相似文献   

16.

To monopolize the scientific data gained by Japanese physicians and researchers from vivisections and other barbarous experiments performed on living humans in biological warfare programs such as Unit 731, immediately after the war the United States (US) government secretly granted those involved immunity from war crimes prosecution, withdrew vital information from the International Military Tribunal for the Far East, and publicly denounced otherwise irrefutable evidence from other sources such as the Russian Khabarovsk trial. Acting in “the national interest” and for the security of the US, authorities in the US tramped justice and morality, and engaged in what the English common law tradition clearly defines as “complicity after the fact.” To repair this historical injustice, the US government should issue an official apology and offer appropriate compensation for having covered up Japanese medical war crimes for six decades. To help prevent similar acts of aiding principal offender(s) in the future, international declarations or codes of human rights and medical ethics should include a clause banning any kind of complicity in any unethical medicine—whether before or after the fact—by any state or group for whatever reasons.  相似文献   

17.
This paper extends standard agency theoretic models to explicitly take into account the presence of multiple criteria at the agent level. Two approaches for this extension are discussed. In the first approach we consider only the minimum information that the principal might posses about the agent’s preferences for different criteria. It can be shown that in this context the principal has limited possibilities to influence the agent’s behaviour. In the second approach a richer information set is considered. In this context it is possible to determine probabilities of alternatives being selected by the agent. We also analyse how these probabilities can be influenced by the principal and how this affects the principal’s net profit. © 1998 John Wiley & Sons, Ltd.  相似文献   

18.
Ethical problems are related to computer data bases, containing data on individuals and groups of persons, as well as to computer knowledge bases, containing general rules and elements of expert systems.In the present essay the following conclusions are made regarding computer data bases: privacy, security, and confidentiality of medical computer data bases should be ensured. This duty should rest with physicians in hospitals. The principle of informed consent should be applied to gathering information which is to be stored and processed by computers. Information stored in computer data bases should not be used for purposes for which the subjects (patients as well as personnel) have not given their consent. In order to decrease the possibility of misuses of medical data bases containing information on individuals, these registers should not be linked to other central data bases.  相似文献   

19.
20.
What comprises ‘data’ varies from one institution to another based on the information which is deemed important by individual institutions. To effectively and efficiently produce, collect, and retain data, an organization develops specific defining characteristics of data to meet its informational needs. Procedures to maintain and retain knowledge among laboratory members and principal investigators will allow for improved efficiency of data collection. Optimization of communication, maintenance of inventories, record keeping, and updating relevant training programs are all critical to supporting the quality and integrity of a particular organization’s data. Concurrent revisions to such procedures will ensure that the definition of data as well as the means by which it is collected and maintained remain appropriate to the needs of the individual organization.  相似文献   

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