How Households Adopt Sustainable Innovations? A Free Decision Enforced by Others

Table 2

Overview of independent variables.

	Study I: Insulation	Study II: Solar thermal energy	Study III: E-mobility
	(n = 233)	(n = 232)	(n = 227)
Technical interest
M	3.48	3.48	3.92
SD	.78	.77	.73
Cronbach’s α	.77	.77	.72
Investment-relevant knowledge
M	3.53	3.13	3.58
SD	.85	.89	.80
Cronbach’s α	N/A	N/A	.79
Eco-social value orientation
M	4.02	4.09	4.52
SD	.56	.58	.63
Cronbach’s α	.62	.65	.79
Social norms
M	2.15	2.32	2.46
SD	1.03	1.17	1.17
Cronbach’s α	N/A	N/A	.85

Note. Most items were measured on a 6-point Likert scale. In studies I and II, investment-relevant knowledge was measured on a 5-point Likert scale. The items were standardized for further analyses.
Cronbach’s α is not available for investment-relevant knowledge and social norms in studies I and II. They were measured with single items in these studies.
n = sample size as in number of participants, M = mean value of given variable in the sample (measured as central tendency of distribution), SD = standard deviation of values of given variable from calculated mean in the sample, and Cronbach’s α = reliability estimate for internal consistency of used scales.