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NOTE Coal miners: nominal or ordinal severity?: captions match the on-screen steps.

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Step 1 of 7. Pneumoconiosis: 371 coal miners in 8 exposure groups, normal < mild < severe.

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Step 2 of 7. Drag the years at the coal face: both models' probabilities update side by side.

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Step 3 of 7. Fitted curves against the observed proportions in each exposure group.

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Step 4 of 7. Proportional odds: AIC 422.92 with 3 parameters, against 425.45 for the nominal model's 4.

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Step 5 of 7. Is proportional odds justified? The 2023 work did not test it.

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Step 6 of 7. Cumulative logits for both severity splits, with parallel and separate-slope fits.

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Step 7 of 7. Brant test p = 0.82, LR test p = 0.99: no evidence against, but little power with 82 cases.