Streszczenie
Paper contains statistical analysis of relationship between different types of taxation and average size of informal sector in OECD countries. Analysis shows that correlation between average tax burden and size of informal sector in slightly positive or does not exist. Use of different types of taxes leads to significant correlations – with higher levels of indirect taxes higher levels of informal sector are related, higher levels of direct taxes are correlated with lower levels of informal sector. It implies conclusion of nonlinear
relationship between variables.