<!doctype s-function-doc system "s-function-doc.dtd" [
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<s-function-doc>
<s-topics>
   <s-topic>rq.object</s-topic>
</s-topics>
<s-title>
Linear Quantile Regression Object 
</s-title>
<s-description>
These are objects of class
<s-expression>
rq. 
</s-expression>
They represent the fit of a linear conditional quantile function model. 
</s-description>
<s-section name=" GENERATION">

This class of objects is returned from the 
<s-expression>rq</s-expression> function 
to represent a fitted linear quantile regression model. 
</s-section>
<s-section name=" METHODS">
The <s-expression>"rq"</s-expression> class of objects has methods for the following generic 
functions: 
<br><br>
<s-expression>coef</s-expression>, 
<s-expression>effects</s-expression>, 
<s-expression>formula</s-expression>, 
<s-expression>labels</s-expression>, 
<s-expression>model.frame</s-expression>, 
<s-expression>model.matrix</s-expression>, 
<s-expression>plot</s-expression>, 
<s-expression>predict</s-expression>, 
<s-expression>print</s-expression>, 
<s-expression>print.summary</s-expression>, 
<s-expression>residuals</s-expression>, 
<s-expression>summary</s-expression>, 
<br><br>
</s-section>
<s-section name=" STRUCTURE">
The following components must be included in a legitimate 
<s-expression>rq</s-expression> object. 
</s-section>
<s-value>
<s-return-component name="coefficients">
the coefficients of the quantile regression fit. 
The names of the coefficients are the names of the 
single-degree-of-freedom effects (the columns of the 
model matrix). 
If the model was fitted by method "br" with ci=T, then
the coefficient component consists of a matrix whose
first column consists of the vector of estimated coefficients
and the second and third columns are the lower and upper
limits of a confidence interval for the respective coefficients.
</s-return-component>
<s-return-component name="residuals">
the residuals from the fit. 
</s-return-component>
<s-return-component name="contrasts">
a list containing sufficient information to construct the contrasts 
used to fit any factors occurring in the model. 
The list contains entries that are either matrices or character vectors. 
When a factor is coded by contrasts, the corresponding contrast matrix 
is stored in this list. 
Factors that appear only as dummy variables and variables in the model 
that are matrices correspond to character vectors in the list. 
The character vector has the level names for a factor or the column 
labels for a matrix. 
</s-return-component>
<s-return-component name="model">
optionally the model frame, if <s-expression>model=T</s-expression>. 
</s-return-component>
<s-return-component name="x">
optionally the model matrix, if <s-expression>x=T</s-expression>. 
</s-return-component>
<s-return-component name="y">
optionally the response, if <s-expression>y=T</s-expression>. 
<br><br>
</s-return-component>
</s-value>
<s-details>
The coefficients, residuals, and effects may be extracted 
by the generic functions of the same name, rather than 
by the <s-expression>$</s-expression> operator.
For pure <s-expression>rq</s-expression> objects this is less critical 
than for some of the inheritor classes. 
Note that the extractor function <s-expression>coef</s-expression> returns a vector with missing values 
omitted.
</s-details>
<s-see>
<s-function name="rq.sgm">rq</s-function>,  <s-function name="coef.sgm">coefficients</s-function>.   </s-see>
<s-keywords>
<s-keyword>librobust</s-keyword>
<s-keyword>classes</s-keyword>
</s-keywords>
<s-docclass>
function
</s-docclass>
</s-function-doc>
