You will be given a definition of a task first, then some input of the task.
Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.

Question: Does data-driven modeling of sleep EEG and EOG reveal characteristics indicative of pre-Parkinson 's and Parkinson 's disease?
Answer: The topics showed visual accordance with the manually scored sleep stages, and the features revealed sleep characteristics containing information indicative of neurodegeneration.
Output:
yes