recalib

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

Functions for fitting and plotting SITAR (Super
Imposition by Translation And Rotation) growth curve models. SITAR is
a shape-invariant model with a regression B-spline mean curve and
subject-specific random effects on both the measurement and age
scales. The model was first described by Lindstrom (1995)
<doi:10.1002/sim.4780141807> and developed as the SITAR method by Cole
et al (2010) <doi:10.1093/ije/dyq115>.

Tim Cole

sitar

Super Imposition by Translation and Rotation Growth Curve
Analysis

recalib function

<dl><dt>xc</dt>
<dd>character vector defining column name(s) of <code>x</code> data to be
recalibrated.</dd>
<dt>yc</dt>
<dd>character vector defining column name(s) of <code>y</code> data to be
recalibrated.</dd>
<dt>id</dt>
<dd>factor defining <code>from</code> and <code>to</code> rows. If <code>NULL</code>
then recalibrate all rows.</dd>
<dt>data</dt>
<dd>dataframe containing <code>xc</code>, <code>yc</code> and <code>id</code>.</dd>
<dt>xcnew</dt>
<dd>column names for replacement columns <code>xc</code>. If default
<code>NULL</code> then use names xcnew1... .</dd>
<dt>ycnew</dt>
<dd>column names for replacement columns <code>yc</code>. If default
<code>NULL</code> then use names ycnew1... .</dd>
<dt>model</dt>
<dd><code>sitar</code> model defining the random effects to be used for
recalibration.</dd>
<dt>from</dt>
<dd>level of <code>id</code> defining existing data (must be a single row
in <code>coef{model}</code>).</dd>
<dt>to</dt>
<dd>level of <code>id</code> defining data to be recalibrated (a single row
in <code>coef{model}</code>).</dd></dl>

Arguments

Tim Cole <a href="/link/tim.cole%40ucl.ac.uk?package=sitar&version=1.4.0" data-mini-rdoc="sitar::tim.cole@ucl.ac.uk">tim.cole@ucl.ac.uk</a>

Author

Recalibrate x, y data using SITAR random effects — recalib

<dl>

<dt>xc</dt>
<dd>character vector defining column name(s) of <code>x</code> data to be
recalibrated.</dd>


<dt>yc</dt>
<dd>character vector defining column name(s) of <code>y</code> data to be
recalibrated.</dd>


<dt>id</dt>
<dd>factor defining <code>from</code> and <code>to</code> rows. If <code>NULL</code>
then recalibrate all rows.</dd>


<dt>data</dt>
<dd>dataframe containing <code>xc</code>, <code>yc</code> and <code>id</code>.</dd>


<dt>xcnew</dt>
<dd>column names for replacement columns <code>xc</code>. If default
<code>NULL</code> then use names xcnew1... .</dd>


<dt>ycnew</dt>
<dd>column names for replacement columns <code>yc</code>. If default
<code>NULL</code> then use names ycnew1... .</dd>


<dt>model</dt>
<dd><code>sitar</code> model defining the random effects to be used for
recalibration.</dd>


<dt>from</dt>
<dd>level of <code>id</code> defining existing data (must be a single row
in <code>coef{model}</code>).</dd>


<dt>to</dt>
<dd>level of <code>id</code> defining data to be recalibrated (a single row
in <code>coef{model}</code>).</dd>

</dl>

Tim Cole <a href='mailto:tim.cole@ucl.ac.uk'>tim.cole@ucl.ac.uk</a>

recalib: Recalibrate x, y data using SITAR random effects

Description

Usage

Value

Arguments

Author

Details