twoway (hist body_mass if species == 1, color(orange%40)) ///
(hist body_mass if species == 2, color(emerald%40)) ///
(hist body_mass if species == 3, color(purple%40)), ///
xtitle("Body Mass (g)") ytitle("Frequency") ///
legend(order(1 "Adelie" 2 "Chinstrap" 3 "Gentoo") pos(1) ring(0) col(1)) ///
plotregion(fcolor(white)) graphregion(fcolor(white))
Figure 1: Histogram of Body Mass by Species
cap drop body_mass?
qui separate body_mass, by(species)
twoway scatter body_mass? flipper_len, ///
mcolor(orange emerald purple) mlab("") ///
msymbol(O T S) ///
xtitle("Flipper Length (mm)") ytitle("Body Mass (g)") ///
legend(order(1 "Adelie" 2 "Chinstrap" 3 "Gentoo") pos(11) ring(0) col(1)) ///
plotregion(fcolor(white)) graphregion(fcolor(white))
Figure 2: Body Mass vs. Flipper Length by Species
qui{
eststo clear
eststo: reg bill_len i.species, robust
eststo: reg bill_len i.species sex, robust
eststo: reg bill_len i.species sex year, robust
}
esttab
------------------------------------------------------------
(1) (2) (3)
bill_len bill_len bill_len
------------------------------------------------------------
1.species 0 0 0
(.) (.) (.)
2.species 10.04*** 10.01*** 10.04***
(21.91) (28.61) (28.60)
3.species 8.713*** 8.698*** 8.693***
(24.71) (30.53) (30.82)
sex 3.694*** 3.694***
(14.54) (14.61)
year 0.324*
(2.02)
_cons 38.79*** 33.28*** -617.9
(178.78) (81.19) (-1.92)
------------------------------------------------------------
N 342 333 333
------------------------------------------------------------
t statistics in parentheses
* p<0.05, ** p<0.01, *** p<0.001
qui{
eststo clear
eststo: reg body_mass i.species, robust
eststo: reg body_mass i.species sex, robust
eststo: reg body_mass i.species sex year, robust
}
esttab
------------------------------------------------------------
(1) (2) (3)
body_mass body_mass body_mass
------------------------------------------------------------
1.species 0 0 0
(.) (.) (.)
2.species 32.43 26.92 27.23
(0.54) (0.55) (0.55)
3.species 1375.4*** 1377.9*** 1377.8***
(23.37) (36.24) (36.15)
sex 667.6*** 667.6***
(19.25) (19.22)
year 3.629
(0.17)
_cons 3700.7*** 2704.8*** -4582.9
(99.06) (49.92) (-0.11)
------------------------------------------------------------
N 342 333 333
------------------------------------------------------------
t statistics in parentheses
* p<0.05, ** p<0.01, *** p<0.001
