Table 3 Independent variables included in multilevel regressions, their definition and data sources

Gender

Gender is a dummy variable taking the value 1 if the surveyed head of household is male and 0 if they are female.

0

1

0.65

0.47

Political Affiliation

A dummy variable taking the value 1 if the household prefers to vote for the German green party (Bündnis 90/die Grünen or Alliance 90/The Greens) and 0 otherwise.

0

1

0.07

0.25

Environmental Concern

A dummy variable equaling 1 if surveyed head of household is a member in any nongovernmental environmental organization and 0 otherwise

0

1

0.13

0.34

Education

A dummy variable taking the value 1 if the head of household at least attained the general qualification for university entrance (highest German school degree) and 0 otherwise.

0

1

0.30

0.46

Age

Individual’s age in years. We also included its squared form in the regression analysis to consider the detected inverted U-shaped relationship between age and a household’s CCOs.

19

88

53.68

13.78

Income

A categorical variable ranging from 1 (less than 500 Euro per month) to 12 (more than 5500 Euro per month)

1

12

6.26

2.71

Urban

The share of people living in an urban municipality within a planning region

9.95

100

49.89

22.61

Prospering

The share of people living in a prospering municipality within a planning region

0

100

64.27

28.82

Green

The share of votes for the German green party (Alliance 90/The Greens) during the general election in 1994

2.60

12.70

6.56

2.33

East

A dummy variables taking the value 1 if the household resides in a region in East Germany or 0 if the household resides in a region in West Germany at the time of the survey. Berlin was coded as 1.

0

1

0.20

0.40