motor data frame has 94 rows and 4 columns. The rows are
obtained by removing replicate values of
time from the dataset
mcycle. Two extra columns are added to allow for strata with
a different residual variance in each stratum.
This data frame contains the following columns:
The time in milliseconds since impact.
The recorded head acceleration (in g).
A numeric column indicating to which of the three strata (numbered 1, 2 and 3) the observations belong.
An estimate of the residual variance for the observation.
v is constant
within the strata but a different
estimate is used for each of the three strata.
The data were obtained from
Silverman, B.W. (1985) Some aspects of the spline smoothing approach to non-parametric curve fitting. Journal of the Royal Statistical Society, B, 47, 1–52.
Davison, A.C. and Hinkley, D.V. (1997) Bootstrap Methods and Their Application. Cambridge University Press.
Venables, W.N. and Ripley, B.D. (1994) Modern Applied Statistics with S-Plus. Springer-Verlag.