## 2 Literature Review and Hypothesis Development
### Theory of Planned Behavior
#### 2.1.5 Environmental Knowledge  
Consumer knowledge is an important aspect of consumer behavior [75], and its comprehension can, in particular, aid companies in an understanding of the information search and data processing behavior of customers. Environmental knowledge (EK) refers to an individual's environmental expertise, knowledge, and other related problems [76]. Persons  
\begin{table}
\begin{tabular}{p{56.9 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Country** & **Authors** & **Sample/Analysis Method** & **Constructs Found Significant** \\ \hline Pakistan & [66] & 673/PLS-SEM/MGA & Warm glow benefits, utilitarian environmental benefits, perceived behavioral control, normative beliefs, eco-literacy, attitude, and subjective norm \\ \hline Pakistan & [1] & 289/PLS SEM & Attitude, policy information campaigns, past purchase experience, and PBC \\ \hline China & [67] & 1472/Logistic regression/SPSS & Incomes, household size, and dwelling areas \\ \hline China & [24] & 305/PLS SEM & Environmental concern, subjective norm, attitude, environmental knowledge, and PBC \\ \hline China & [68] & 477/SEM/AMOS & Personal norm, PBC, awareness of consequences, attitude, ascription of responsibility, and subjective norm. \\ \hline India & [69] & 300/Multiple Regression/SPSS & Perceived product risk, skepticism towards label claims, price sensitivity, perceived personal inconvenience, and subjective norms \\ \hline South-Korea & [70] & 304/Logistic regression/SPSS & Price and eco-label \\ \hline Pakistan & [1] & 396/PLS SEM & Innovativeness, PBC, attitude, insecurity, discomfort, and optimism, \\ \hline Malaysia & [5] & 210/PLS SEM & Attitude, PBC, and moral norms \\ \hline China & [57] & 253/SEM/AMOS & Attitude, PBC, subjective norms, and residual effect \\ \hline South-Korea & [9] & 1050/SEM/AMOS & Trust, social responsibility, environmental knowledge, and perceived cost. \\ \hline \hline \end{tabular}  
* Source: Authors compilation. Note: PLS-SEM = Partial Least Square Structural Equation Modeling, MGA = Multi-group Analysis, SPSS = Statistical Packages for Social Science, AMOS = Analysis of a Moment Structures.  
\end{table}
Table 1: The Buying Intention of Energy-Efficient Appliances in Asian Countries.  
with specific ecological knowledge tend to have a positive attitude to ecological behavior and are strongly prepared to take action. [PERSON] [77] discovered that households having a greater ecological awareness are more likely to purchase energy-efficient vehicles and that research has revealed that ecological knowledge has a favorable impact on customer attitude with respect to green products [78; 79; 47]. [PERSON] et al. [80] demonstrated that EK influences the attitude of residents towards green products, which in turn affects their intention to purchase green items [6; 81]. The following hypotheses are hereby presented:  
**Hypothesis 8**.: _Environmental knowledge is significantly and positively related to the attitude of residents towards the purchase of EEHA._  
**Hypothesis 9**.: _Environmental knowledge is significantly and positively related to the intention of residents to buy EEHA._