The present study evaluates the validity and reliability of the research model in designing a tax collection framework based on tax justice within the context of e-government. The main objective is to examine the credibility of the measurement instruments and assess the structural performance of the model in measuring the relationships among different variables. In this regard, convergent validity and reliability of the variables were evaluated. Overall, the results indicate that the instruments used in this study possess high credibility, ensuring the trustworthiness of the measurements.
Furthermore, the discriminant validity of the model was assessed using the Fornell-Larcker criterion and the HTMT index. According to the Fornell-Larcker criterion, a construct should have a stronger correlation with itself than with other constructs. The analysis of the Fornell-Larcker matrix confirmed that the correlation values of each construct with itself on the main diagonal were higher than those with other constructs, thus supporting appropriate discriminant validity. Additionally, the HTMT criterion—recommended for more complex models and cases with overlapping factor loadings—showed that the HTMT values for all construct pairs were below 0.9. This finding indicates that the constructs are effectively distinguished from one another, with no unnecessary correlations.
The overall conclusion of the study demonstrates that the research model enjoys satisfactory validity and reliability, and that the employed measurement tools are highly credible. Moreover, the model effectively explains the relationships among variables, with the structural model fit indices showing strong predictive power and a good overall fit. Therefore, the proposed research model is suitable for hypothesis testing and further analyses.
In the final part of the study, recommendations are provided to improve the efficiency of the tax system and achieve tax justice. These include strengthening cooperation and data exchange among different governmental bodies through the design of integrated information systems, enabling smooth and rapid transfer of tax-related data across institutions. Such measures can enhance inter-agency coordination, reduce errors and disruptions in information processing, and ultimately improve transparency and reduce corruption. It is also recommended that tax systems be developed based on modern technologies, allowing taxpayers to perform all tax-related activities online in a simple and transparent manner, while ensuring the security of their information.