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Table 2.

Watson and Crick’s triple-helix model of DNA (no competing model). Evidence points are numbered in the first column E1 to E5, for the target or alternative theory. The last row shows the posterior probability, the percentage change between the prior and posterior, and the likelihood ratio (LR) as defined in Eq. 2. The posterior is equal to 0.5 * 0.6 * 0.6 * 0.3 * 0.3 * 0.3/(0.5 * 0.6 * 0.6 * 0.3 * 0.3 * 0.3 + 0.5 * 0.5 * 0.5 * 0.5 * 0.5 * 0.5)

Probability	Estimate	Description	Evidence
P(T)	0.5	neutral	prior of T
P(∼T)	0.5	neutral	1 − prior
P(E1\|T)	0.6	weakly consistent	analogy to alpha helix
P(E1\|∼T)	0.5	neutral	hypothetical null model
P(E2\|T)	0.6	weakly consistent	X-ray data (28 A repeat)
P(E2\|∼T)	0.5	neutral	hypothetical null model
P(E3\|T)	0.3	strongly inconsistent	water content too low
P(E3\|∼T)	0.5	neutral	hypothetical null model
P(E4\|T)	0.3	strongly inconsistent	bond lengths/angles wrong
P(E4\|∼T)	0.5	neutral	hypothetical null model
P(E5\|T)	0.3	strongly inconsistent	positive ions not found
P(E5\|∼T)	0.5	neutral	hypothetical null model
P(T\|E1–E5)	0.24	disconfirm	% change = −52.0, LR = 0.31

Probability	Estimate	Description	Evidence
P(T)	0.5	neutral	prior of T
P(∼T)	0.5	neutral	1 − prior
P(E1\|T)	0.6	weakly consistent	analogy to alpha helix
P(E1\|∼T)	0.5	neutral	hypothetical null model
P(E2\|T)	0.6	weakly consistent	X-ray data (28 A repeat)
P(E2\|∼T)	0.5	neutral	hypothetical null model
P(E3\|T)	0.3	strongly inconsistent	water content too low
P(E3\|∼T)	0.5	neutral	hypothetical null model
P(E4\|T)	0.3	strongly inconsistent	bond lengths/angles wrong
P(E4\|∼T)	0.5	neutral	hypothetical null model
P(E5\|T)	0.3	strongly inconsistent	positive ions not found
P(E5\|∼T)	0.5	neutral	hypothetical null model
P(T\|E1–E5)	0.24	disconfirm	% change = −52.0, LR = 0.31

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