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¹⁰ Hix, , Noury, and Roland, , Democratic Politics in the European ParliamentGoogle Scholar. Almost 3 per cent of the time MEPs vote against both their party group and national party.

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¹⁷ Hix, , Noury, and Roland, , Democratic Politics in the European Parliament, p. 497.Google Scholar

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²⁸ The model in Column 2 was estimated using WinBUGS 1.41. For direct comparison to the maximum likelihood results from Column 1, a second Bayesian model was also fitted using Andrew Martin and Kevin Quinn’s MCMCpack package for R, which yielded nearly equivalent results. Full details including the prior distributions and the likelihood function for the model in Table 4 are provided in the Appendix.

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³⁰ This is based on 95 per cent posterior confidence intervals. The full listing of posterior probabilities for every party in both the predicted and actual party groups, as well as a posterior ratio with confidence intervals, is available from the authors.