Summery the results of the interaction terms.

This study rigorously examines the complex interplay between financial technology (Fintech), financial inclusion, and their collective effects on economic growth in developing nations. Employing a robust panel regression methodology enhanced by Panel-Corrected Standard Errors (PCSE) and Feasible Generalized Least Squares (FGLS) techniques, this research analyzes an extensive dataset comprising 108 countries categorized into low, lower-middle, and upper-middle income levels across four pivotal years (2011, 2014, 2017, and 2021). Our analysis focuses on two key dimensions of Fintech—specifically, the adoption of digital payments and e-commerce via mobile technologies—and traditional financial access indicators, including the density of ATMs, bank branches, and active banking accounts. The findings demonstrate a predominantly positive effect of Fintech variables on economic growth, particularly through improved digital payment systems. Conversely, traditional financial inclusion metrics frequently show a negative correlation with growth trajectories. Notably, our research underscores a significant positive interaction between digital payment usage and ATM density, indicating a synergistic relationship that enhances the performance of traditional banking systems. In contrast, a substitutability effect arises, where increased dependence on mobile technologies diminishes the relevance of traditional financial infrastructure, potentially obstructing broader economic growth. These findings carry critical policy implications, advocating for a cohesive strategy that fosters both Fintech innovations and traditional financial sectors to maximize economic growth and inclusivity. A deliberate emphasis on synchronizing innovative financial solutions with the strengthening of conventional banking is essential for promoting sustainable economic development in these resource-constrained regions.

本研究严谨考察了金融科技（Financial Technology, Fintech）、金融普惠及其共同作用对发展中国家经济增长的复杂交互影响。本研究采用经面板校正标准误（Panel-Corrected Standard Errors, PCSE）与可行广义最小二乘法（Feasible Generalized Least Squares, FGLS）方法优化的稳健面板回归分析框架，对覆盖108个国家的大型数据集展开实证分析；这些国家按收入水平划分为低收入、中低收入与中高收入组别，研究周期涵盖2011、2014、2017及2021四个关键年份。
本研究聚焦金融科技的两大核心维度——具体而言，即基于移动技术的数字支付与电子商务应用——同时纳入传统金融可得性指标，包括ATM机密度、银行网点密度与活跃银行账户数量。
研究结果表明，金融科技变量整体对经济增长呈现正向促进效应，其中数字支付系统的优化作用尤为突出。与之相对，传统金融普惠指标往往与经济增长轨迹呈负相关关系。值得注意的是，本研究揭示了数字支付使用与ATM机密度之间存在显著的正向交互效应，表明二者存在协同关系，可有效提升传统银行系统的运营效能。反之则存在替代效应：对移动技术的依赖度提升会削弱传统金融基础设施的价值，或对整体经济增长形成阻碍。
上述研究结果具有重要的政策启示意义，主张应采取协同发展策略，同步推动金融科技创新与传统金融行业提质升级，以最大化实现经济增长与金融普惠效益。在这些资源约束型地区，有意识地协调创新型金融解决方案与传统银行业的强化升级，对于促进可持续经济发展至关重要。