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Table 1 Descriptions and expected direction of occurrence probability (ѱ) models for Megathyrsus maximus [M], Leucaena leucocephala [L], and Uniola virgata [U] along the 570-m bulldozed trail in the Ensenada sector of the Guánica Forest. All models tested for significance at α = 0.05

From: Spread of common native and invasive grasses and ruderal trees following anthropogenic disturbances in a tropical dry forest

Hypothesis Model Structure of model Expected results
1. [All]: no influence of any factor over species ѱ (.) β 0
2. [M, L]: negative influence of trail distance from road ѱ (Dist_z) β 0 + β 1 (Dist_z) β 1 < 0
[U]: positive influence of trail distance from road ѱ (Dist_z) β 0 + β 1 (Dist_z) β 1 > 0
3. [All]: positive influence of distance and temporal patterns ѱ (Time) β 0 + β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) β 1 < 0, β 2 < 0, β 3 > 0, β 4 > 0
4. [M]: negative influence of U. virgata and L. leucocephala presence ѱ (NatColo) β 0 + β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) + β 5 (U. virgata and L. leucocephala) β 1 < 0, β 2 < 0,
β 3 > 0, β 4 < 0, β 5 < 0
5. [U]: negative influence of M. maximus and L. leucocephala presence ѱ (InvColo) β 0 + β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) + β 5 (M. maximus and L. leucocephala) β 1 ≤ 0, β 2 < 0,
β 3 > 0, β 4 < 0, β 5 < 0
6. [L]: negative influence of M. maximus and U. virgata presence ѱ (GrassColo) β 0 + β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) + β 5 (M. maximus and U. virgata) β 1 ≤ 0, β 2 < 0,
β 3 > 0, β 4 < 0, β 5 > 0
7. [All]: negative influence of the presence of native trees and other vegetation ѱ (NatVeg) β 0 + β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) + β 5 (other vegetation) β 1 ≤ 0, β 2 < 0,
β 3 > 0, β 4 < 0, β 5 < 0
8. [M]: negative influence of all effects on M. maximus presence ѱ (AllColoNat) β 0+ β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) + β 5 (U. virgata and L. leucocephala) + β 6 (other vegetation) β 1 ≤ 0, β 2 < 0,
β 3 > 0, β 4 < 0, β 5 < 0, β 6 < 0
9. [U]: negative influence of all effects on U. virgata presence ѱ (AllColoInv) β 0+ β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) + β 5 (M. maximus and L. leucocephala) + β 6 (other vegetation) β 1 ≤ 0, β 2 < 0,
β 3 > 0, β 4 < 0, β 5 < 0, β 6 < 0
10. [L]: negative influence of all effects on L. leucocephala presence ѱ (AllColoGrass) β 0+ β 1 (Dist_z) + β 2 (July 2012) + β 3 (December 2012) + β 4 (July 2013) + β 5 (M. maximus and U. virgata) + β 6 (other vegetation) β 1 ≤ 0, β 2 < 0,
β 3 > 0, β 4 < 0, β 5 < 0, β 6 < 0