TABLE 5.

Rates of correct classification (ARCC) of environmental samples, based on known source locations, for different reductions in numbers of species classifications and drugs for three DA methods: results from cross-validation analysis using DA training rules from fecal samples

Approach% of isolates classified in agreement, best group for identificationa
LinearQuadraticEpanechnikov
Twelve drugs; eight species26.0, swine (39)18.7, swine (42)22.5, dairy cattle (39)
Reduced drugs; eight species25.4, swine (34)19.8, swine (37)17.1, dairy cattle (39)
Twelve drugs; six species37.9, ruminantsb (56)28.9, swine (50)31.0, ruminantsb (66)
Reduced drugs; six species36.9, ruminantsb (58)30.2, swine (50)30.0, swine (50)
Twelve drugs; five species40.2, livestockc (70)26.3, equine (29)33.6, livestockc (56)
Reduced drugs; five species39.8, livestockc (69)27.2, livestockc (31)30.4, equine (41)
Twelve drugs; four species57.2, food animalsd (85)32.7, food animalsd (36)43.1, food animalsd (57)
Reduced drugs; four species57.4, food animalsd (85)35.4, food animalsd (35)38.1, equine (41)
  • a The value in parentheses following the best group for identification is the percentage of isolates correctly identified in the group.

  • b The ruminant group is a combination of beef and dairy cattle and sheep.

  • c The livestock group is a combination of beef and dairy cattle, sheep, and swine.

  • d The food animal group is a combination of beef and dairy cattle, sheep, swine, and poultry.