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arXiv · 1307.5396

Star graphs induce tetrad correlations: for Gaussian as well as for binary variables

Nanny Wermuth·Giovanni M. Marchetti
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Abstract

Tetrad correlations were obtained historically for Gaussian distributions when tasks are designed to measure an ability or attitude so that a single unobserved variable may generate the observed, linearly increasing dependences among the tasks. We connect such generating processes to a particular type of directed graph, the star graph, and to the notion of traceable regressions. Tetrad correlation conditions for the existence of a single latent variable are derived. These are needed for positive dependences not only in joint Gaussian but also in joint binary distributions. Three applications with binary items are given.

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Nanny Wermuth, Giovanni M. Marchetti. 2014-03-11. Star graphs induce tetrad correlations: for Gaussian as well as for binary variables. https://arxiv.org/abs/1307.5396

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