PROBLEM TO BE SOLVED: To enable determination of sleep apnea syndrome without imposing a burden on a person to be measured. SOLUTION: Biological vibration data based on body movement or pressure change during sleep of a subject is obtained. Then, from the acquired biological vibration data, a plurality of feature quantities or frequency spectra are calculated at regular intervals. Furthermore, from the calculated features or frequency spectra, the sleep stage is discriminated using a plurality of decision trees having branching conditions for discriminating the sleep stage, and then the classification criteria of the decision tree used for the determination. Based on the discrimination result obtained by the combination of, sleep apnea syndrome is determined. Alternatively, the power spectrum of the frequency component included in the biological vibration data is calculated, and the contribution degree of the power spectrum of the frequency component to the classification by a plurality of decision trees having different branching conditions is calculated and calculated. The sleep apnea syndrome is determined based on. [Selection diagram] FIG. 5【課題】被測定者への負担をかけずに睡眠時無呼吸症候群の判定が行えるようにする。【解決手段】被測定者の睡眠中の体動または圧力変化に基づいた生体振動データを得る。そして、取得した生体振動データから、一定時間ごとに複数の特徴量または周波数スペクトルを算出する。さらに、算出した複数の特徴量または周波数スペクトルから、睡眠段階を判別するための分岐条件を持った複数の決定木を用いて睡眠段階を判別した後、その判断に使用された決定木の分類基準の組み合わせで得られる判別結果に基づいて、睡眠時無呼吸症候群の判定を行う。或いは、生体振動データに含まれる周波数成分のパワースペクトルを算出し、その周波数成分のパワースペクトルについて、それぞれ異なる分岐条件を持った複数の決定木による分類への寄与度を算出し、算出した寄与度に基づいて睡眠時無呼吸症候群の判定を行う。【選択図】図５
