This section illustrates how to modify axis tick marks and control grid lines. For example, you can specify the following statement to request tick marks ranging from –4 to 2 in the Y-axis:
layout Overlay / yaxisopts=(linearopts=(tickvaluelist=(-4 -3 -2 -1 0 1 2)));
The LINEAROPTS= option is used for standard linearly scaled axes (as opposed to log-scaled axes). You use the TICKVALUELIST= to specify the tick marks.
You can control the grid lines by using the GRIDDISPLAY= suboption in the YAXISOPTS= option. Typically, you specify either
GRIDDISPLAY=AUTO_OFF (grid lines are not displayed unless the GraphGridLines
element in the current style contains DisplayOpts="ON"
) or GRIDDISPLAY=AUTO_ON (grid lines are displayed unless the GraphGridLines
element in the current style contains DisplayOpts="OFF"
). Here, the template is modified by specifying GRIDDISPLAY=AUTO_ON for both axes. The following statements produce Output 22.1.4:
proc template; define statgraph Stat.Robustreg.Graphics.QQPlot; notes "Q-Q Plot for Standardized Robust Residuals"; dynamic _DEPLABEL Residual _byline_ _bytitle_ _byfootnote_; BeginGraph; entrytitle "Analysis of Residuals"; Layout Overlay / yaxisopts=(gridDisplay=Auto_On linearopts=(tickvaluelist=(-4 -3 -2 -1 0 1 2)) label=("Standardized Robust Residual for " _DEPLABEL)) xaxisopts=(gridDisplay=Auto_On label="Quantile"); SCATTERPLOT y=eval (SORT(DROPMISSING(RESIDUAL))) x=eval ( PROBIT((NUMERATE(SORT(DROPMISSING(RESIDUAL))) -0.375)/(0.25 + N(RESIDUAL)))) / primary=true markerattrs=GraphDataDefault(symbol=CircleFilled) rolename=(q=eval( PROBIT((NUMERATE(SORT(DROPMISSING(RESIDUAL))) -0.375)/(0.25 + N(RESIDUAL)))) s=eval (SORT(DROPMISSING(RESIDUAL)))) tip=(q s) tiplabel=(q= "Quantile" s="Residual"); lineparm slope=eval (STDDEV(RESIDUAL)) Y=eval (MEAN(RESIDUAL)) X=0 / clip=false lineattrs=GraphReference(color=red pattern=dash) extend=true; EndLayout; if (_BYTITLE_) entrytitle _BYLINE_ / textattrs=GRAPHVALUETEXT; else if (_BYFOOTNOTE_) entryfootnote halign=left _BYLINE_; endif; endif; EndGraph; end; run; ods graphics on; proc robustreg data=stack plots=qqplot; ods select QQPlot; model y = x1 x2 x3; run;
Output 22.1.4: Q-Q Plot with Modified Y-Axis Tick Marks and Grids
You can restore the default template by running the following step:
proc template; delete Stat.Robustreg.Graphics.QQPlot / store=sasuser.templat; run;
For more information about grid lines, see the section Modifying the Style to Show Grid Lines.