The Multivariate Largest Lyapunov Exponent as an Age-Related Metric of Quiet Standing Balance

Figure 2

The results of the determinism test and stationarity test for the acceleration time series of a typical subject. (a) and (b) are the results of the hip, (c) and (d) are the results of the knee, (e) and (f) are the results of the ankle, and (g) and (h) are the results of COP in AP. (a), (c), (e), and (g) are the embedding space, and (b), (d), (f), and (h) are the average cross-prediction error for all the possible combinations of and . The average values of all are 0.1839, 0.2215, 0.1398, and 0.8951 (for the time series of hip, knee, ankle, and COP in AP, resp.).

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)