Modern computational neuroscience employs diverse software tools and multidisciplinary expertise to analyze heterogeneous brain data. The classical problems of gathering meaningful data, fitting specific models, and discovering appropriate analysis and visualization tools give way to a new class of computational challenges—management of large and incongruous data, integration and interoperability of computational resources, and data provenance. We designed, implemented and validated a new paradigm for addressing these challenges in the neuroimaging field. Our solution is based on the LONI Pipeline environment [3], [4], a graphical workflow environment for constructing and executing complex data processing protocols. We developed study-design, database and visual language programming functionalities within the LONI Pipeline that enable the construction of complete, elaborate and robust graphical workflows for analyzing neuroimaging and other data. These workflows facilitate open sharing and communication of data and metadata, concrete processing protocols, result validation, and study replication among different investigators and research groups. The LONI Pipeline features include distributed grid-enabled infrastructure, virtualized execution environment, efficient integration, data provenance, validation and distribution of new computational tools, automated data format conversion, and an intuitive graphical user interface. We demonstrate the new LONI Pipeline features using large scale neuroimaging studies based on data from the International Consortium for Brain Mapping [5] and the Alzheimer's Disease Neuroimaging Initiative [6]. User guides, forums, instructions and downloads of the LONI Pipeline environment are available at http://pipeline.loni.ucla.edu.

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Finding effective methods for developing an ensemble of models has been an active research area of large-scale data mining in recent years. Models learned from data are often subject to some degree of uncertainty, for a variety of reasons. In classification, ensembles of models provide a useful means of averaging out error introduced by individual classifiers, hence reducing the generalization error of prediction.The plurality voting method is often chosen for bagging, because of its simplicity of implementation. However, the plurality approach to model reconciliation is ad-hoc. There are many other voting methods to choose from, including the anti-plurality method, the plurality method with elimination, the Borda count method, and Condorcet's method of pairwise comparisons. Any of these could lead to a better method for reconciliation.In this paper, we analyze the use of these voting methods in model reconciliation. We present empirical results comparing performance of these voting methods when applied in bagging. These results include some surprises, and among other things suggest that (1) plurality is not always the best voting method; (2) the number of classes can affect the performance of voting methods; and (3) the degree of dataset noise can affect the performance of voting methods. While it is premature to make final judgments about specific voting methods, the results of this work raise interesting questions, and they open the door to the application of voting theory in classification theory.

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People often use multiple metrics in image processing, but here we take a novel approach of mining the values of batteries of metrics on image processing results. We present a case for extending image processing methods to incorporate automated mining of multiple image metric values. Here by a metric we mean any image similarity or distance measure, and in this paper we consider intensity-based and statistical image measures and focus on registration as an image processing problem. We show how it is possible to develop meta-algorithms that evaluate different image processing results with a number of different metrics and mine the results in an automated fashion so as to select the best results. We show that the mining of multiple metrics offers a variety of potential benefits for many image processing problems, including improved robustness and validation.