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The book "Mathematics and Archaeology", consisting of 25 chapters by a range of international scholars in archaeology, will be published by Chapman & Hall in 2014. The present document, written as an invited Epilogue to the book, recounts the rediscovery of the book 275 years later by an...
Persistent link: https://www.econbiz.de/10010891944
Hierarchical clustering is a popular method for finding structure in multivariate data, resulting in a binary tree constructed on the particular objects of the study, usually sampling units. The user faces the decision where to cut the binary tree in order to determine the number of clusters to...
Persistent link: https://www.econbiz.de/10009002566
Correspondence analysis, when used to visualize relationships in a table of counts (for example, abundance data in ecology), has been frequently criticized as being too sensitive to objects (for example, species) that occur with very low frequency or in very few samples. In this statistical...
Persistent link: https://www.econbiz.de/10009323414
The case of two transition tables is considered, that is two square asymmetric matrices of frequencies where the rows and columns of the matrices are the same objects observed at three different time points. Different ways of visualizing the tables, either separately or jointly, are examined. We...
Persistent link: https://www.econbiz.de/10005827504
Dual scaling of a subjects-by-objects table of dominance data (preferences, paired comparisons and successive categories data) has been contrasted with correspondence analysis, as if the two techniques were somehow different. In this note we show that dual scaling of dominance data is equivalent...
Persistent link: https://www.econbiz.de/10005827514
The generalization of simple correspondence analysis, for two categorical variables, to multiple correspondence analysis where they may be three or more variables, is not straighforward, both from a mathematical and computational point of view. In this paper we detail the exact computational...
Persistent link: https://www.econbiz.de/10005827533
In the analysis of multivariate categorical data, typically the analysis of questionnaire data, it is often advantageous, for substantive and technical reasons, to analyse a subset of response categories. In multiple correspondence analysis, where each category is coded as a column of an...
Persistent link: https://www.econbiz.de/10005772006
A biplot, which is the multivariate generalization of the two-variable scatterplot, can be used to visualize the results of many multivariate techniques, especially those that are based on the singular value decomposition. We consider data sets consisting of continuous-scale measurements, their...
Persistent link: https://www.econbiz.de/10005772056
It is shown how correspondence analysis may be applied to a subset of response categories from a questionnaire survey, for example the subset of undecided responses or the subset of responses for a particular category. The idea is to maintain the original relative frequencies of the categories...
Persistent link: https://www.econbiz.de/10005772169
The singular value decomposition and its interpretation as a linear biplot has proved to be a powerful tool for analysing many forms of multivariate data. Here we adapt biplot methodology to the speciffic case of compositional data consisting of positive vectors each of which is constrained to...
Persistent link: https://www.econbiz.de/10005772202