recalib() R function from [sitar]

Recalibrate x, y data using SITAR random effects

A function to recalibrate x,y data using SITAR random effects


recalib(xc, yc, id = NULL, data, xcnew = NULL, ycnew = NULL, model, from, to)

xc: character vector defining column name(s) of x data to be recalibrated.
yc: character vector defining column name(s) of y data to be recalibrated.
id: factor defining from and to rows. If NULL

then recalibrate all rows.
data: dataframe containing xc, yc and id.
xcnew: column names for replacement columns xc. If default NULL then use names xcnew1... .
ycnew: column names for replacement columns yc. If default NULL then use names ycnew1... .
model: sitar model defining the random effects to be used for recalibration.
from: level of id defining existing data (must be a single row in coef{model}).
to: level of id defining data to be recalibrated (a single row in coef{model}).

Returns the dataframe data with the from rows of xc and yc recalibrated.

recalib recalibrates the values of xc and yc based on model. xc values are changed to:

(xc-c(coef[from,'b']))*exp(coef[from,'c']-coef[to,'c'])+coef[to,'b'].

yc values are changed to: yc-coef[from,'a']+coef[to,'a'].