This three way classification complicates the discussion of Cooperative Naturalism.
Our experiments in four way classification are competitive with previous results.
Results for five way classification on the manually annotated set using CRFs and windowed feature vectors are depicted in Tables 8, 9 and 10, with each table representing results for each five way classification problem.
Separate five way classification experiments are undertaken for each of the three cases with Intervention, Outcome Measure and Participants.
Using a CRF model trained on Set 2, performance is tested on the manually annotated test set, Set 1, for four way classification into the rhetorical roles.
There is some evidence that it is easier to identify Intervention, Outcome Measure and Participant sentences in structured abstracts, as seen in the five way classification results for Set 1 in Tables 8, 9 and 10.
Five way classification experiments are conducted on each of Sets O, I and P. 15-fold cross-validation is conducted in each case, comparing a baseline feature vector with one that incorporates the windowed features.
Examples of sentences labeled as Intervention, Outcome Measure and Participants in Set 1. Results for four way classification on the manually annotated test set trained on the structured set, Set 2 are documented in Table 7.
