PROBLEM TO BE SOLVED: To provide a technique with which a state of a person is accurately recognized.SOLUTION: The time series waveforms of frequencies are obtained from time series waveforms of biological signals sampled from an upper body of a person, and further time series waveforms of frequency gradients are obtained. The gradient time series waveforms are frequency-analyzed, and in the relation of logarithmic power spectral density and a logarithmic frequency, a branching point of a regression line is captured, and a state is determined using the appearing position of the branching point and the shape of the regression line, etc. Since the position of the branching point and the shape of the regression line, etc., can be patterned according to the state of the person, the state is easily and accurately determined.COPYRIGHT: (C)2012,JPO&INPIT【課題】 人の状態をより正確に把握する技術を提供する。【解決手段】 人の上体から採取した生体信号の時系列波形から周波数の時系列波形を求め、さらに、周波数傾きの時系列波形を求める。この傾き時系列波形を周波数解析し、対数パワースペクトル密度と対数周波数の関係において、回帰直線の分岐点を捉え、分岐点の現れた位置、回帰直線の形等を用いて状態を判定するが、この分岐点の位置や回帰直線の形等は、人の状態に応じて類型化できるため、状態判定を簡易かつ正確に行うことができる。【選択図】 図4