Advances in Statistics http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. On Agreement Tables with Constant Kappa Values Sun, 24 Aug 2014 08:23:00 +0000 http://www.hindawi.com/journals/as/2014/853090/ Kappa coefficients are standard tools for summarizing the information in cross-classifications of two categorical variables with identical categories, here called agreement tables. When two categories are combined the kappa value usually either increases or decreases. There is a class of agreement tables for which the value of Cohen’s kappa remains constant when two categories are combined. It is shown that for this class of tables all special cases of symmetric kappa coincide and that the value of symmetric kappa is not affected by any partitioning of the categories. Matthijs J. Warrens Copyright © 2014 Matthijs J. Warrens. All rights reserved. The Fence Methods Thu, 24 Jul 2014 12:13:29 +0000 http://www.hindawi.com/journals/as/2014/830821/ This paper provides an overview of a recently developed class of strategies for model selection, known as the fence methods. It also offers directions of future research as well as challenging problems. Jiming Jiang Copyright © 2014 Jiming Jiang. All rights reserved. A Simplified Approach for Two-Dimensional Optimal Controlled Sampling Designs Sun, 25 May 2014 12:59:33 +0000 http://www.hindawi.com/journals/as/2014/875352/ Controlled sampling is a unique method of sample selection that minimizes the probability of selecting nondesirable combinations of units. Extending the concept of linear programming with an effective distance measure, we propose a simple method for two-dimensional optimal controlled selection that ensures zero probability to nondesired samples. Alternative estimators for population total and its variance have also been suggested. Some numerical examples have been considered to demonstrate the utility of the proposed procedure in comparison to the existing procedures. Neeraj Tiwari and Akhil Chilwal Copyright © 2014 Neeraj Tiwari and Akhil Chilwal. All rights reserved.