Customizing legend of twoway graph.

[Sumedha Gupta]

Dear All,

I am making a twoway graph as follows:

twoway (scatter daysMED week if  dateWeek<2841 & dateWeek>2715, color(gs10)) ///
(lowess daysMED week if  dateWeek<2841 & dateWeek>2715, bwidth(2) lcolor(black)) ///
(scatter daysMED week if dateWeek>2841 & dateWeek<2848, color(gs10)  ) ///
(lowess daysMED week if dateWeek>2841 & dateWeek<2848 , bwidth(2) lcolor(black)) ///
(scatter daysMED week if dateWeek>2847 & dateWeek<2970, color(gs10)) ///
(lowess daysMED week if dateWeek>2847 & dateWeek<2970, bwidth(2) lcolor(black)), xlabel(2767(20)2922, angle(45)) xline(2841) xline(2848) ///
xtitle("")  legend(col(2) row(3)) legend(size(vsmall))

It looks as follows:



I would like to change the legend to:
2013w12-2014w33 Period before tramadol scheduling
2014w34-2014w41 Period after tramadol scheduling and before hydrocodone upscheduling
2014w42-2016w16 Period after hydrocodone upscheduling.

How can I do that?

Similarly, in another graph:

twoway (lfitci daysMED week if dateWeek>2833 & dateWeek<2842 ) ///
(lfitci daysMED week if dateWeek>2840 & dateWeek<2849 ) ///
(lfitci daysMED week if dateWeek>2847 & dateWeek<2855 ), xlabel(2834 "2014w27" 2836 "2014w29" 2838 "2014w31" 2840 "2014w33" ///
2842 "2014w35" 2844 "2014w37" 2846 "2014w39" 2848 "2014w41" 2850 "2014w43" 2852 "2014w45" 2854 "2014w47", ///
angle(45)) xline(2841) xline(2848) ///
xtitle("")  legend(col(2) row(3)) legend(size(vsmall))

which looks as follows:



I would again like to have the legend as :

2014w27-2014w33 Period before tramadol scheduling
2014w34-2014w41 Period after tramadol scheduling and before hydrocodone upscheduling
2014w42-2014w47 Period after hydrocodone upscheduling.

Same question, how can I customize this legend as well?

I will be grateful for your help.
Sincerely,
Sumedha.

[Roman Mostazir]

Same procedure for both:


2014w42-2016w16 Period after hydrocodone upscheduling

legend(order(1 "2013w12-2014w33: before tramadol " 3 "2014w34-2014w41: after tramadol and before hydrocodone" 5 "after hydrocodone"))

[Sumedha Gupta]

Thank you Roman. It works, but can I supress the picture of the *dot* before the legend?



Thank you again for your help.
Sincerely,
Sumedha.

[Nick Cox]

For the legend to be worth adding at all, you need different marker symbols and/or colours for the three groups of data.

Otherwise you are better off with a customised xtitle()

I have to be curious. You are using Stata weeks, but Stata weeks each year always start on 1 January and end with a 8 or 9 day week ending 31 December, so there are always 52 weeks in each year. That doesn't match any other definition of week I've seen used for recording data.

[Roman Mostazir]

Chiming with Nick, what is the point of legend if the legend marker is not used? You probably then need to use legend(off) option and add meaningful 'xtitle' (yet not a suitable choice). I think, it would be better if your choose different colors for markers using 'mcol()' option after each 'scatter' function instead 'gs10' color scheme for all and get different color of legends.

[Sumedha Gupta]

Thank you so much Nick and Roman. You are right. I dropped the legend (legend(off)) and instead included a caption. Does the job! Thank you again.

[Eric de Souza]

Be useful for others if you could post the commands you gave and the final result. Thanks.