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A unified approach to model selection using the likelihood ratio test. Fraser Lewis Lucy Gilbert Adam Butler. H. Methods in Ecology and Evolution Podcast. Ixodes ricinus. Likelihood ratio tests are widely used for comparing nested models
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A unified approach to model selection using the likelihood ratio test Fraser Lewis Lucy Gilbert Adam Butler H Methods in Ecology and Evolution Podcast
Likelihood ratio tests are widely used for comparing nested models They involve calculating the LRTS, which is twice the difference in log-likelihoods between the two models LRTS = 2 * (log LB– log LA) Compute a p-value by calculating the distribution of the LRTS under the null hypothesis that the simpler model is true Our paper demonstrates that a similar approach can also be used with non-nested models
Simple example Simulate 100 observations from Yi ~ Poisson(μi) where log(μi) = 3 + 0.5xi + 0.01zi Consider two models: Model A: Yi ~ Poisson(μi) where log(μi) = a + bxi Model B: Yi ~ Poisson(μi) where log(μi) = a + bzi also be used with non-nested models
Thank you for listening If you have any questions, please don’t hesitate to get in touch with us: [Fraser new email] adam@bioss.ac.uk l.gilbert@macaulay.ac.uk