D |
qualitative variable; D = 1 if operator died as a result of injuries sustained in accident, D = 0 otherwise D = 0.048. |

HS = |
where N is the number of head injuries incurred. |

NS = |
where K is the number of neck injuries sustained. |

K1 = |
.5MV2, measured in foot pounds, where M (measured in slugs) = WT/g, where WT is the weight of the operator measured in pounds and g is the gravitational constant measured in ft/sec2. V is the crash speed of the motorcycle measured in ft/sec. K1 = 3506.33. |

K2 = |
.5MV2, measured in foot-pounds, where V is the relative velocity of the motorcycle and other vehicle. K2 = 3793.39. |

H |
"qualitative variable; H = 1 if operator wore a helmet, H = 0 otherwise. H = 0.43." |

HI |
interaction variable equal to product of H and I where I is the normal component of impact velocity to the helmet measured in miles per hour. HI = 3.64. |

A |
age of operator measured in number of years. A = 26.25. |

BA |
blood alcohol level corrected to time of accident, measured in number (integer) of hundredths of 1% of blood alcohol, 0 __<__ BA __<__ 31. BA = 0.62. |

EA |
"qualitative variable, EA = 1 if evasive action was attempted by the operator and if the action was considered appropriate for the situation. EA = 0.33." |

EX |
EX = EX for 0 __<__ EX __<__ EX* and EX = EX* otherwise. EX* = 96 and EX = 44.44. |

HW |
interaction variable equal to product of H and W where W is the weight of the helmet in pounds. HW = 1.16. |