Smallpox and Season: Reanalysis of Historical Data

Table 2

Monthly weather patterns and the effective reproduction number of smallpox in Northwest frontier province, India, from 1890–1921.

Variable	β ^†	S.E.^‡	𝑡-Ratio	𝑃
Intercept	1.579	0.139	11.37	<.01
Rainfall (inch)	0.008	0.015	0.51	.61
Absolute humidity	−1.169	0.319	−3.66	<.01
Cosine	−0.181	0.078	−2.32	.02
Sine	−0.211	0.064	−3.29	<.01

^†Parameter coefficient; ^‡Standard error; 𝑟²=0.057 (𝐹-ratio = 5.67, 𝑃<.01), dependent variable = effective reproduction number, Durbin-Watson = 2.600.