```help paragr

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Title

paragr -- Parallel graphing of a coefficient across different equations

Syntax

paragr variable [, options]

Description

paragr provides a fast and easy way to compare a coefficient across
different equations within an estimation.

It can used to visualize the parallel assumption of ordered logit or
the equality of coefficients for quantile regression, etc.

By default paragr plots a scatter graph. A quadratic fitted line
(qfit) can be superimposed.

Twoway graph options can be specified for the entire graph, or
separately for the scatter graph or for the qfit graph.

Options

+------+
----+ Main +-------------------------------------------------------------

scatter( ) standard options for scatter graph. Use this to set color,
range, etc

qfit a quadratic fitted line is superimposed.

qfit( ) standard options for qfit graph. Use this to set color,
range, etc

gen( ) a prefix for saving the plot points as variables.

nodraw suppress the display of graph

saving( ) save as a Stata graph

name(name[, replace]) specifies the name of the graph

Examples

* reg3
sysuse auto, clear
reg3 (price weight rep78) (price weight rep78 mpg) (price weight
paragr rep78, xtitle(Equation) gen(reg3_) saving(mygraph)

* sqreg
sysuse auto, clear
sqreg price mpg rep78 headroom length, q(.10 .20 30 .40 .50 .60 .70
.80 .90) reps(25)
paragr rep78, qfit

* Unconstrained gologit
sysuse auto, clear
egen money=cut(price), group(5)
gologit money headroom mpg weight length turn displacemen
paragr displacement

* constrained gologit2 from ssc (need Stata 8.2 or better)
sysuse auto, clear
egen money=cut(price), group(5)
gologit2 money headroom mpg weight length turn displacement, auto
paragr weight, qfit ytitle(odds ratios) xtitle(cut)

Remarks

qfit requires at least two equations.

Coefficient values goes on the y-axis.

Acknowledgement

Nick Cox provided detailed and helpful suggestions.

Author