Stata da o'zgaruvchilarni kodlash va label qo'yish

Label lar Stata da ma'lumotlarni tushunarli qiladi.

O'zgaruvchiga label qo'yish

* O'zgaruvchi labeli
label variable daromad "Oylik daromad (so'm)"
label variable yosh "Yosh (to'liq yillar)"
label variable ta_lim "Ta'lim (yillar)"

Qiymat labeli

* Label yaratish
label define jinsi_label 0 "Ayol" 1 "Erkak"
label define ta_lim_label 1 "Maktab" 2 "Kollej" 3 "Oliy" 4 "Magistr"

* O'zgaruvchiga bog'lash
label values jinsi jinsi_label
label values ta_lim_daraja ta_lim_label

* Tekshirish
tabulate jinsi
codebook jinsi

Kategorik o'zgaruvchi yaratish (recode)

* Yosh guruhlarini yaratish
recode yosh ///
    (15/24 = 1 "Yosh") ///
    (25/44 = 2 "O'rta yosh") ///
    (45/64 = 3 "Katta yosh") ///
    (65/max = 4 "Keksa"), ///
    generate(yosh_guruh)

label variable yosh_guruh "Yosh guruhi"

Dummy o'zgaruvchilar

* Bitta dummy
generate shahar_toshkent = (shahar == "Toshkent")

* Ko'p kategoriyadan dummy
tabulate ta_lim_daraja, generate(ta_lim_d)
* ta_lim_d1, ta_lim_d2, ... yaratiladi

* i. prefiksi bilan regressiyada
regress daromad i.ta_lim_daraja yosh

Missing qiymatlar

* Ko'rish
misstable summarize
misstable patterns

* -99 ni missing ga aylantirish
mvdecode daromad yosh, mv(-99)

* Missing ni o'chirish
drop if missing(daromad)