Species analysis
Statistical exploration
Classification trees
Variables
Purple Finch
Occurred the most disproportionately in westernmost Oregon hexagons
with stream density more than 2 miles of stream per sq. mi. Moving
eastward, it is likely to occur in hexagons with more than 7% mountain
hemlock montane forest or (less probably), with more than 4% mixed
forest with Douglas-fir dominant. Among eastern Oregon hexagons, it
occurred mainly where July minimum temperature (hex. min.) is 1-4�
C and where some of the hexagon is in private ownership. The logistic
regression analysis showed positive or negative association with big
sagebrush shrubland, mixed conifer forest (Douglas-fir dominant),
Douglas-fir - w. hemlock - red cedar forest, elevation (hex. avg.), the
extent of public land, April precipitation (hex. min.), and June
precipitation (hex. min.).
Classification trees
Hexagons: using ONHP land cover classification (accuracy score: 91.40)
Squares: using ONHP land cover classification (accuracy score: 88.28)
Hexagons: using AVHRR land cover classification (accuracy score: 91.63)
