Table 1.

Stochastic mapping test for correlation using the wind pollination and nectar example. Pollination mode has two states, animal-pollinated (A) and wind-pollinated (W), and nectar also has two states, present (0) or absent (1). Hypothetical observed and expected probabilities of finding each character state and state combination (e.g. A, 0) are given. The difference (d) is the observed minus the expected for each cell and D is the sum of the absolute value of the individual differences.

	Observed				Expected
	Pollination				Pollination			Difference (d)
Nectar	A	W		Nectar	A	W
0	0.60	0.02	0.62	0	0.53	0.09	0.62	0.07	−0.07
1	0.26	0.12	0.38	1	0.33	0.05	0.38	−0.07	0.07
	0.86	0.14			0.86	0.14		D = 0.28