Table 4.

Regression slope (depth) and variance estimates for the random factors and their relative contribution to the uncertainty associated with individual segment observations of cover of soft-substrate vegetation

Region	Slope for depth	Variance estimates			Relative uncertainty
		Site	Diver	Residual	Site (%)	Diver (%)	Residual (%)
Macroalgae cover
Gulf of Bothnia inner	−0.195	0.5973	0.0761	2.9342	117	32	455
Gulf of Bothnia outer	−0.104	0.6882	0.1789	4.6862	129	53	771
Baltic Proper inner	–0.204	0.4343	0.1009	2.3636	93	37	365
Baltic Proper outer	−0.111	0.4441	0.0478	2.7812	95	24	430
West coast inner	−0.201	0.2500	0.0435	0.8276	65	23	148
West coast outer	−0.113	0.1174	0.1431	0.8003	41	46	145
Soft-substrate vegetation cover
Gulf of Bothnia inner	−0.438	0.3541	0.1138	5.4000	81	40	921
Gulf of Bothnia outer	−0.559	0.4858	0.3161	5.3020	101	75	900
Baltic Proper inner	−0.551	0.4227	0.1119	4.9460	92	40	824
Baltic Proper outer	−0.286	0.3270	0.6859	6.5139	77	129	1184

The relative uncertainty was calculated as $exp\left(\sqrt{V}\right)-1$, based on lognormal distribution theory