Robustness test.

Based on the data from the China Family Panel Studies (CFPS) in 2018, the relationship between internet use and informal workers’ wages and its internal mechanism were empirically discussed using the ordinary least squares and endogenous switching regression(ESR) model. The study found that internet use could significantly raise the level of wages of informal workers, and this conclusion still holds after the endogenous problem was solved through the endogenous switching regression model. Further research found that the influences of the internet use on informal workers’ wages was heterogeneous. In other words, internet use has a more obvious impact on the wages of informal workers aged 31 to 40, 41 to 50, and 51 to 60 with the educational level of university and above in cities and towns, while it has a significant negative impact on wages of informal workers aged 16 to 20.