Table 5 Results of interaction detecting.

From: Heterogeneity and the determinants of PM2.5 in the Yangtze River Economic Belt

Factors

2000

2007

2017

Factors

2000

2007

2017

pgdp ∩ popd

NE (0.682)

NE (0.745)

BE (0.709)

wind ∩ prec

NE (0.624)

NE (0.488)

NE (0.749)

pgdp ∩ urba

NE (0.281)

NE (0.420)

BE (0.421)

wind ∩ ndvi

NE (0.570)

NE (0.486)

NE (0.814)

pgdp ∩ indu

NE (0.370)

NE (0.225)

NE (0.472)

wind ∩ topo

NE (0.666)

NE (0.794)

BE (0.843)

popd ∩ urba

NE (0.654)

BE (0.757)

BE (0.748)

prec ∩ ndvi

NE (0.442)

NE (0.427)

NE (0.373)

popd ∩ indu

BE (0.657)

NE (0.747)

BE (0.762)

prec ∩ topo

NE (0.602)

BE (0.757)

NE (0.841)

urba ∩ indu

NE (0.397)

NE (0.432)

NE (0.516)

ndvi ∩ topo

NE (0.649)

NE (0.842)

BE (0.847)

  1. NE nonlinear enhancement, BE bifactor enhancement.