Table 1. Literature review of Taiwan’s underground economy in recent years.

Taiwan related literature	Analysis period	Estimation method	Genetic variable and influence direction
Dai and Sun (2003)	1962–2002	MIMIC model	Tax burden(+),
Wang et al. (2006)	1961–2003	MIMIC model	Tax burden(−),
Wang et al. (2012)	1962–2003	OLS model	Direct tax + (−) Indirect tax − (−)
Ho and Cai (2014)	1961–2012	OLS model	Tax burden(+),
Lin Zhensheng(2020)	1976–2016	OLS model	Tax Burden(−),

Note: 1. The positive and negative signs in brackets represent the direction of the influence of genetic variables on the underground economy. 2. Among the tax rate variables adopted by Wang et al. (2012), direct tax+ and direct tax—respectively represent the increase and decrease of direct tax rate, and indirect tax+ and indirect tax—respectively represent the increase and decrease of indirect tax rate