Table 1 Variable definitions and descriptive statistics

Adoption

1 if respondent has used residue-based biogas, 0 otherwise

0.22 (0.41)

OB from relatives (OB_r)

1 if respondent obtain observational learning from relatives’ adoption of residue-based biogas, 0 otherwise

0.51 (0.50)

OB from neighbors (OB_n)

1 if respondent obtain observational learning from neighbors’ adoption of residue-based biogas, 0 otherwise

0.59 (0.49)

OB from cadres (OB_c)

1 if respondent obtain observational learning from cadres’¹ adoption of residue-based biogas, 0 otherwise

0.54 (0.50)

OB from cooperative members (OB_o)

1 if respondent obtain observational learning from cooperative members’ adoption of residue-based biogas, 0 otherwise

0.31 (0.46)

OB from technical instructors (OB_t)

1 if respondent obtain observational learning from technical instructors’ adoption of residue-based biogas, 0 otherwise

0.32 (0.47)

Positive WOM from relatives (WOM_rp)

1 if respondent obtain positive word-of-mouth learning from relatives, 0 otherwise^a

0.24 (0.43)

Positive WOM from neighbors (WOM_np)

1 if respondent obtain positive word-of-mouth learning from neighbors, 0 otherwise^a

0.27 (0.44)

Positive WOM from cadres (WOM_cp)

1 if respondent obtain positive word-of-mouth learning from cadres¹, 0 otherwise^a

0.13 (0.34)

Positive WOM from cooperative members (WOM_op)

1 if respondent obtain positive word-of-mouth learning from cooperative members, 0 otherwise^a

0.04 (0.19)

Positive WOM from technical instructors (WOM_tp)

1 if respondent obtain positive word-of-mouth learning from technical instructors, 0 otherwise^a

0.07 (0.25)

Negative WOM from relatives (WOM_rn)

1 if respondent obtain negative word-of-mouth learning from relatives, 0 otherwise^a

0.21 (0.40)

Negative WOM from neighbors (WOM_nn)

1 if respondent obtain negative word-of-mouth learning from neighbors, 0 otherwise^a

0.22 (0.42)

Negative WOM from cadres (WOM_cn)

1 if respondent obtain negative word-of-mouth learning from cadres¹, 0 otherwise^a

0.11 (0.31)

Negative WOM from cooperative members (WOM_on)

1 if respondent obtain negative word-of-mouth learning from cooperative members, 0 otherwise^a

0.03 (0.18)

Negative WOM from technical instructors (WOM_tn)

1 if respondent obtain negative word-of-mouth learning from technical instructors, 0 otherwise^a

0.09 (0.29)

Trust in relatives (Tr)

1 if respondent trusts relatives, 0 otherwise^b

0.41 (0.49)

Trust in neighbors (Tn)

1 if respondent trusts neighbors, 0 otherwise^b

0.73 (0.45)

Trust in cadres (Tc)

1 if respondent trusts cadres¹, 0 otherwise^b

0.62 (0.49)

Trust in cooperative members (To)

1 if respondent trusts cooperative members, 0 otherwise^b

0.65 (0.47)

Trust in technical instructors (Tt)

1 if respondent trusts technical instructors, 0 otherwise^b

0.58 (0.49)

Gender

1 if respondent is male; 0 if female

0.56 (0.50)

Age

Respondent’s age

57.52 (10.94)

Education

Schooling of respondents (in years)

6.43 (3.75)

Labor

Number of individuals in the household that are aged 16 or more but below 65 years old

3.13 (1.41)

Household income

Total household income in 2017 (10 000 Yuan)^c

6.96 (7.92)

Subsidy

1if subsidy is provided for those who use residue-based biogas

0.23 (0.42)

Risk perception

Risk perception of the adoption of residue-based biogas^d

2.39 (1.01)

Cost-effective perception

Cost-effective perception of the adoption of residue-based biogas ^d

3.95 (0.89)

Plain

1 if household is located in plain, 0 otherwise

0.26 (0.44)

Hill

1 if household is located in hill, 0 otherwise

0.69 (0.46)

Mountains

1 if household is located in mountains, 0 otherwise

0.05 (0.22)