Rank | Case 1 | Case 2 | Case 3 | Case 4 |

1 | Raw acceleration data in Y direction | Average of VM for three axes | SD in Y direction | Sum of counts’ Log-energy in Y direction |

2 | Raw acceleration data in X direction | Peak-to-peak amplitude in Y direction | Membership of Ntile Groups (N=5) of counts’ vector magnitude | |

3 | Raw acceleration data in Z direction | IQR in Y direction | Amplitude of dominant frequency of counts in Y direction | |

4 | Peak-to-peak amplitude in X direction | Average counts in Y direction | ||

5 | Membership of Ntile Groups (N=5) of vector magnitude | Vector magnitude of average counts in X, Y and Z directions | ||

6 | SD in x direction | Sum of counts in Y direction | ||

7 | IQR in X direction | counts’ vector magnitudes | ||

8 | SD in Z direction | Sum of counts’ Log-energy in X | ||

9 | Signal power in Y direction | Signal power of counts in Y | ||

10 | Sum of Log-energy in Y direction | Dominant frequency of counts in Y direction |

IQR, Interquartile Range; SD, Standard Deviation; VM, Vector Magnitude.