This study examines whether income distribution in Thailand has a property of scale invariance or self-similarity across years. By using the data on income shares by quintile and by decile of Thailand from 1988 to 2021, the results from 306-pairwise Kolmogorov-Smirnov tests indicate that income distribution in Thailand is statistically scale-invariant or self-similar across years with p-values ranging between 0.988 and 1.000. Based on these empirical findings, this study would like to propose that, in order to change income distribution in Thailand whose pattern had persisted for over three decades, the change itself cannot be gradual but has to be like a phase transition of substance in physics.

翻译：本研究考察了泰国收入分配在跨年度间是否具有尺度不变性或自相似性。利用1988年至2021年泰国按五等分和十等分分组计算的收入份额数据，通过306组成对柯尔莫哥洛夫-斯米尔诺夫检验的结果表明：泰国收入分配在统计上具有跨年度的尺度不变性或自相似性，p值介于0.988至1.000之间。基于这些实证发现，本研究提出：若要改变已持续三十余年的泰国收入分配格局，这种改变不能是渐进的，而必须如同物理学中物质的相变过程。