topic Re: Boxplot for different treatments in SAS Procedures

Boxplot for different treatments

hua — Thu, 11 Jan 2018 20:28:02 GMT

Hi all,

I want to get a boxplot figure like the following:

My dataset include thousands of stations, and for each station it have results for 2 treatments (similar as black and blue in the figure) and 12 months (Jan to Dec) and a total as annual (x-axis has 13 labels).

The variables in my dataset are: station time(Jan-Dec,Ann) Treatment1 Treatment2

Anyone has any idea about how to get the figure?

By the way, I used the following code, but could only do it one treatment by one treatment.

proc sort data = mydata;
  by time;
run;

proc boxplot data = mydata;
  plot treatment1 * time;
run;

Re: Boxplot for different treatments

ballardw — Thu, 11 Jan 2018 20:57:54 GMT

You would need to transpose the data so that each treatment is a single record with a variable to contain a treatment identifier

Try something like:

data plot;
   set my data;
   TreatName='Treatment 1'; Value=Treatment1;output;
   TreatName='Treatment 2'; Value=Treatment2;output;
   drop treatment1 treatment2;
run;

and plot by TreatName *time

Re: Boxplot for different treatments

hua — Thu, 11 Jan 2018 21:03:42 GMT

Plot by TreatName*time doesn't work, it shows an error that The variable TreatName in the DATA= data set should be a numeric variable.

Re: Boxplot for different treatments

ballardw — Thu, 11 Jan 2018 21:13:16 GMT

Try moving to the more updated graphics where you can use numeric or text values for grouping and categorizing:

proc sgplot data=plot;
   vbox value /  category=time group=treatname;
run;

This uses ODS graphics options so if the display is too narrow or what have you the size can be adjusted with Height and Width options:

ODS graphics / height=4in width=8in;

proc sgplot ..

would have a display 8 inches wide and 4 inches tall for example.

Re: Boxplot for different treatments

hua — Thu, 11 Jan 2018 21:16:43 GMT

And after transpose my data by:

data plot;
   set mydata;
   TreatName='Treatment 1'; Value=Treatment1;output;
   TreatName='Treatment 2'; Value=Treatment2;output;
   drop treatment1 treatment2;
run;

I used

proc sgplot data=plot;
   vbox value / category=time group=TreatName;
run;

I got the figures , but I want to have max and min as a line without outliers, and also want to get the line at value 0.

Also, anyone know how to use two axis instead of only one?

Thanks!

Re: Boxplot for different treatments

hua — Thu, 11 Jan 2018 21:19:35 GMT

Yes, I tried these codes! it works. But do you know how to use max/min instead of outliers? And get the line y=0?

Re: Boxplot for different treatments

ballardw — Thu, 11 Jan 2018 21:30:09 GMT

@hua wrote:

, but I want to have max and min as a line without outliers, and also want to get the line at value 0.

Also, anyone know how to use two axis instead of only one?

Thanks!

You would have to explain HOW you want to use two axis.

There are a fair number of options in the online help for the VBOX statement in SGPLOT.

Such as EXTREME to show max and min lines to the maximum and minimum as an option on the vbox statement

Refline 0 / axis=y; will dray a line at y=0.

I have to say from you graph that the two treatments don't belong in the same graph as the ranges are significantly different;

Perhaps Proc SGPANEL with:

panelby treatname / onepanel rows=2 uniscale=column;

Re: Boxplot for different treatments

hua — Thu, 11 Jan 2018 21:33:55 GMT

Thanks! I will check the options online. The ranges are so different, that's why I want to use two y-axises, one for each.

Re: Boxplot for different treatments

ballardw — Thu, 11 Jan 2018 21:48:59 GMT

@hua wrote:
Thanks! I will check the options online. The ranges are so different, that's why I want to use two y-axises, one for each.

I don't think you'll be happy with the results of any of the 2 axis solutions with the modified data. I recommended modifying the data as that would be needed for the older boxplot for many approaches.

You might go back to the original data and try overlaying two vbox statements as that is one of the big improvements with the SGgraphics. You can't overlay just anything but two vbox should work:

proc sgplot data= mydata;
   vbox treatment1 / category=time
                     extreme
                     
   ;
   vbox treatment2 / category=time 
                     extreme
                     y2axis
   ;
   refline 0;
run;