Hello people, I am in need for testing Marginal Homogeneity for sparse (more then 2X2) matrixes.
After searching, what I found by now is that for more then 2 by 2 matrixes, one turns to "stuart maxwell tests" that are available in two packages: irr - see: stuart.maxwell.mh coin - see: mh_test But I couldn't find in the documentation how valid the results are for sparse matrixes, and if the validity is indeed compromised (as I suspect it might be), I wasn't able to find an out-of-the-box alternative function to use. A search in google gave me a link to this article: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V8V-45F5P9B-5&_user=1535420&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1096547725&_rerunOrigin=google&_acct=C000053610&_version=1&_urlVersion=0&_userid=1535420&md5=604554a739739d90ae72b3a60ce81a00 named "Comparing marginal distributions of large, sparse contingency tables" Which sounds good, but the abstract suggests a more complex solution then I know how to code in my current stage (e.g: "*This article describes alternative approaches that are much more feasible. We recommend a pseudo ML approach that obtains model parameter estimates by treating repeated responses as independent and uses a jackknife to estimate the covariance matrix of those estimates. We test marginal homogeneity using a Wald statistic, or by adapting the efficient score statistic from the independent-samples case."*) This leaves me with the following questions: 1) How can one know how "badly" the sparsity hearts the assumptions of the stuart maxwell test? 2) Is there a simple alternative for this test? (and how to use it?) 3) Is there a not-so-simple alternative for this test? (and how to use it?) Many thanks, Tal ---------------------------------------------- My contact information: Tal Galili E-mail: tal.gal...@gmail.com Phone number: 972-52-7275845 FaceBook: Tal Galili My Blogs: http://www.talgalili.com (Web and general, Hebrew) http://www.biostatistics.co.il (Statistics, Hebrew) http://www.r-statistics.com/ (Statistics,R, English) [[alternative HTML version deleted]]
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