308,855 research outputs found

    Cluster Failure Revisited: Impact of First Level Design and Data Quality on Cluster False Positive Rates

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    Methodological research rarely generates a broad interest, yet our work on the validity of cluster inference methods for functional magnetic resonance imaging (fMRI) created intense discussion on both the minutia of our approach and its implications for the discipline. In the present work, we take on various critiques of our work and further explore the limitations of our original work. We address issues about the particular event-related designs we used, considering multiple event types and randomisation of events between subjects. We consider the lack of validity found with one-sample permutation (sign flipping) tests, investigating a number of approaches to improve the false positive control of this widely used procedure. We found that the combination of a two-sided test and cleaning the data using ICA FIX resulted in nominal false positive rates for all datasets, meaning that data cleaning is not only important for resting state fMRI, but also for task fMRI. Finally, we discuss the implications of our work on the fMRI literature as a whole, estimating that at least 10% of the fMRI studies have used the most problematic cluster inference method (P = 0.01 cluster defining threshold), and how individual studies can be interpreted in light of our findings. These additional results underscore our original conclusions, on the importance of data sharing and thorough evaluation of statistical methods on realistic null data

    Characterizing HCI Research in China: Streams, Methodologies and Future Directions

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    This position paper takes the first step to attempt to present the initial characterization of HCI research in China. We discuss the current streams and methodologies of Chinese HCI research based on two well-known HCI theories: Micro/Marco-HCI and the Three Paradigms of HCI. We evaluate the discussion with a survey of Chinese publications at CHI 2019, which shows HCI research in China has less attention to Macro-HCI topics and the third paradigms of HCI (Phenomenologically situated Interaction). We then propose future HCI research directions such as paying more attention to Macro-HCI topics and third paradigm of HCI, combining research methodologies from multiple HCI paradigms, including emergent users who have less access to technology, and addressing the cultural dimensions in order to provide better technical solutions and support

    Death of mixed methods?: Or the rebirth of research as a craft

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    The classification by many scholars of numerical research processes as quantitative and other research techniques as qualitative has prompted the construction of a third category, that of ‘mixed methods’, to describe studies that use elements from both processes. Such labels might be helpful in structuring our understanding of phenomena. But they can also inhibit our activities when they serve as inaccurate or limiting descriptors. Based on the observation that mixed methods is fast becoming a common research approach in the social sciences, this paper questions whether the assumptions that are used and perpetuated by mixed methods are valid. The paper calls for a critical change in how we perceive research, in order to better describe actual research processes. A more ethological taxonomy of the mechanisms underlying research structures and processes is posited to encourage creative thinking around alternatives to the three purported paradigms of quantitative, qualitative and mixed methods. This ‘return to basics’ seeks to encourage new and innovative research designs to emerge, and suggests a rebirth of research from the ashes of mixed methods

    Research Design, as Independent of Methods

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    Objectives •Readers of this chapter should be in a better position to: •Understand the process of research design •Place their own and others work within a full cycle or programme of ongoing research •Understand why good research almost always involves a mixture of evidence •Defend themselves from those who want numbers and text to be enemies rather than allies •Argue that good research is more ethical for society than poor researc

    White matter and task-switching in young adults: A Diffusion Tensor Imaging study

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    The capacity to flexibly switch between different task rules has been previously associated with distributed fronto-parietal networks, predominantly in the left hemisphere for phasic switching sub-processes, and in the right hemisphere for more tonic aspects of task-switching, such as rule maintenance and management. It is thus likely that the white matter (WM) connectivity between these regions is critical in sustaining the flexibility required by task-switching. This study examined the relationship between WM microstructure in young adults and task-switching performance in different paradigms: classical shape-color, spatial and grammatical tasks. The main results showed an association between WM integrity in anterior portions of the corpus callosum (genu and body) and a sustained measure of task-switching performance. In particular, a higher fractional anisotropy and a lower radial diffusivity in these WM regions were associated with smaller mixing costs both in the spatial task-switching paradigm and in the shape-color one, as confirmed by a conjunction analysis. No association was found with behavioral measures obtained in the grammatical task-switching paradigm. The switch costs, a measure of phasic switching processes, were not correlated with WM microstructure in any task. This study shows that a more efficient inter-hemispheric connectivity within the frontal lobes favors sustained task-switching processes, especially with task contexts embedding non-verbal components
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