Graphing Interactions for Visual Inspection

[jess1955]

Hello All,

I am having difficulty fitting a interaction graph over a histogram.

The primary issue is the x-axis extends beyond the observations that I have on the histogram. Additionally, the right y-axis should be the variable TE with proper magnitude.



The code I am using i as follows (this is the complete code):
xtgls flnfdiflow96dollars bitsumoecdweighted lnrgdpch lnpop econgrowth inflation resourcedepletion agreementwithdevcountry wtomemberdummy polcon3 bitsumoecdweightedpolcon3 te ie de c.lnrgdpch#c.te c.ie#c.lnrgdpch c.de#c.lnrgdpch, corr(ar1) force

sort lnrgdpch
matrix b=e(b)
matrix V=e(V)

scalar b2=b[1,2]
scalar b14=b[1,14]

scalar varb2=V[2,2]
scalar varb14=V[14,14]

scalar covb2b14=V[2,14]


scalar list b2 b14 varb2 varb14 covb2b14

generate MVZ=((_n-6)/100)

replace MVZ=. if _n>2720

gen conbx=b2+b14*MVZ if _n<2720

gen consx=sqrt(varb2+varb14*(MVZ^2)+2*covb2b14*MVZ)
gen ax=1.96*consx
gen upperx=conbx+ax
gen lowerx=conbx-ax

gen where=-0.045 *****This is potentially where the problem lies****
gen pipe = "|"
egen tag_te = tag(te)
egen tag_gdp = tag(lnrgdpch)

gen yline=0

graph twoway hist lnrgdpch, width(0.5) percent color(gs14) yaxis(2)
|| scatter where lnrgdpch if tag_gdp, plotr(m(b 4)) ms(none) mlabcolor(gs5) mlabel(pipe) mlabpos(6) legend(off)
|| line conbx MVZ, clpattern(solid) clwidth(medium) clcolor(black) yaxis(1),
|| line upperx MVZ, clpattern(dash) clwidth(thin) clcolor(black)
|| line lowerx MVZ, clpattern(dash) clwidth(thin) clcolor(black)
|| line yline MVZ, clwidth(thin) clcolor(black) clpattern(solid)
|| ,
xlabel(-2 0 2 4 6 8 10 12, nogrid labsize(2))
ylabel(-0.05 0 .05 .1 .15 .2 .25, axis(1) nogrid labsize(2))
ylabel(0 2 4 6 8 10 12 14 16, axis(2) nogrid labsize(2))

I apologize for the excessive code. But I realize my issues with the graph may stem from how I built the interaction and CIs.

Any help would be great.

Best,
Jesse

[jess1955]

Reposting graph

[Friedrich Huebler]

The range of the x-axis can be limited by adding if conditions to the line commands. For example:

line conbx MVZ if MVZ>6 & MVZ<11

There is no variable TE in your graph command.

[jess1955]

Hi Friedrich,

thank you for your reply.

You will notice that TE is in the interaction effect that is being graphed. When I run with your suggestion it simply shortens the line but does not condense the graph.

[Friedrich Huebler]

Please show your code and the resulting graph (see Statalist FAQ, section 12).