Table 6.

Analysis of FBG incidence using reduced multiple variable models for determining residual deviance, odds ratio, and SE

Added variable	Residual deviance	df	LRT		Variable class	Estimate	SE	Odds ratio
			DR	Pr > χ2
Intercept	-	-	-	-	-	−19.3	1.5	-
Year	1,125.5	1	25.8	<0.0001	2019	−1.5	0.3	4.7
					2020	0a	0a	1
Region	927.6	2	0	<0.0001	Oromia	1.6	0.4	0.2
					Amhara	4.06	0.9	57.9
					Tigray	0a	0a	1
Zone	820.9	8	70.08	<0.0001	N/Shewa (Oromia)	3.6	0.9	0.3
					S/W/Shewa	−1	1.1	0.04
					W/Shewa	−1.5	0.9	0.2
					Arsi	2.3	0.9	0.1
					F/Special Zone	0a	0a	1
					N/Shewa (Amhara)	1.6	0.4	4.8
					S/Gondar	0.1	0.6	1.1
					S/Wollo	0a	0a	1
					S/Tigray	0a	0a	1
Crop growth stage	805.08	4	9.8	0.0436	Seedling	−2.1	0.9	2.4
					Vegetative	−1.1	0.7	4.6
					Flowering	−1.2	0.7	3.07
					Podding	−0.9	0.7	2.5
					Maturity	0a	0a	1
Crop density	801.2	2	1.6	0.46	Low (<25/m2)	−0.2	0.3	1.4
					Medium (25/m2)	−0.3	0.3	1.2
					High (>25/m2)	0a	0a	1
Cropping system	784.15	1	14.3	0.0002	Rotation	−24.7	0a	0a
					Mono-cropping	0a	0a	1
Cropping pattern	783.5	1	1.8	0.19	Sole	0.7	0.49	0.5
					Mixed	0a	0a	1
Altitude	674.4	2	51	<0.0001	Low (1,900–2,200)	−2.6	0.5	0.08
					Mid (2,201–2,399)	−1.1	0.2	0.3
					High (>2,400)	0a	0a	1
Weed density	647.95	1	31.08	<0.0001	Low (30–100/m2)	−1.1	0.2	0.09
					High (>100/m2)	0a	0a	1
Soil type	615.31	2	27.8	<0.0001	Cambisol	−1.2	0.6	3.4
					Vertisol	−2.5	0.7	11.9
					Nitosol	0a	0a	1
Fertilizer application	614.8	2	0.6	0.74	Inorganic	−0.15	0.24	1.2
					Organic	0.1	0.44	0.9
					Not applied	0a	0a	1
Fungicide	564.7	1	42.9	<0.0001	Sprayed	−1.42	0.22	4.1
					Unsprayed	0a	0a	-

FBG, faba bean gall; df, degrees of freedom; LRT, likelihood ratio test; DR, deviance reduction; Pr, probability of a χ² value exceeding the deviance reduction, estimates from the model with all independent variables added; SE, standard error.

^aReference group.