An Empirical Analysis of the Coupling Coordination among Decomposed Effects of Urban Infrastructure Environment Benefit: Case Study of Four Chinese Autonomous Municipalities

Table 6

Results of panel unit root tests.

	Series	Fisher ADF		Fisher PP		IPS
		Constant	Trend and constant	Constant	Trend and constant	Constant	Trend and constant
Levels	Coupling coordination degree ()
	Treating waste effect ()
	Purifying air effect ()
	Regulating climate effect ()

Note: lags are all selected automatically by AIC and SC standard.
means significant at confidence level 10%.
means significant at confidence level 5%.
means significant at confidence level 1%.