86,348 research outputs found
An Evaluation of the Sustainability of Global Tuna Stocks Relative to Marine Stewardship Council Criteria
The Marine Stewardship Council (MSC) has established a program whereby a fishery may be certified as being sustainable. The sustainability of a fishery is defined by MSC criteria which are embodied in three Principles: relating to the status of the stock, the ecosystem of which the stock is a member and the fishery management system. Since many of these MSC criteria are comparable for global tuna stocks, the MSC scoring system was used to evaluate nineteen stocks of tropical and temperate tunas throughout the world and to evaluate the management systems of the Regional Fishery Management Organizations (RFMO) associated with these stocks
A Fully Unsupervised Texture Segmentation Algorithm
This paper presents a fully unsupervised texture segmentation algorithm by using a modified discrete wavelet frames decomposition and a mean shift algorithm. By fully unsupervised, we mean the algorithm does not require any knowledge of the type of texture present nor the number of textures in the image to be segmented. The basic idea of the proposed method is to use the modified discrete wavelet frames to extract useful information from the image. Then, starting from the lowest level, the mean shift algorithm is used together with the fuzzy c-means clustering to divide the data into an appropriate number of clusters. The data clustering process is then refined at every level by taking into account the data at that particular level. The final crispy segmentation is obtained at the root level. This approach is applied to segment a variety of composite texture images into homogeneous texture areas and very good segmentation results are reported
Fletcher-Turek Model Averaged Profile Likelihood Confidence Intervals
We evaluate the model averaged profile likelihood confidence intervals
proposed by Fletcher and Turek (2011) in a simple situation in which there are
two linear regression models over which we average. We obtain exact expressions
for the coverage and the scaled expected length of the intervals and use these
to compute these quantities in particular situations. We show that the
Fletcher-Turek confidence intervals can have coverage well below the nominal
coverage and expected length greater than that of the standard confidence
interval with coverage equal to the same minimum coverage. In these situations,
the Fletcher-Turek confidence intervals are unfortunately not better than the
standard confidence interval used after model selection but ignoring the model
selection process
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