| ride comfort index at time t |
| peak value of acceleration in T = (t − 3,t) (3 seconds just before time t) |
| peak absolute value of deceleration in T |
| average value of jerk in T |
| effective value of jerk in the case of positive value of j(T) |
| effective value of jerk in the case of negative value of j(T) |
| error term |
| constant term |
| partial regression coefficient |