People wiggle a lot and getting these variations identified with very high accuracy, both in precision and recall, is tough because that's what it takes to get a professional coach to believe in you.
球场上会发生很多突然的变动， 要在查准率和查全率方面 准确识别这些变化 是相当困难的， 但只有这样， 才能让专业教练相信你的技术。