Definition: 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.
Input: Question: Is direct observation a valid criterion for estimating physical activity and sedentary behavior?
Answer: This study provides evidence that DO can be used as a criterion measure of absolute intensity in free-living validation studies.
Output:
yes