** Biostat 212: Lecture 2 Exploring
*Lab 2: live coding demo
*August 1, 2017


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*Set up
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clear all //clear any open data sets 
pwd //check working directory

cd "/Users/kristenaiemjoy/Box Sync/_Teaching/Biostat 212/Biostat212.2017/Labs/Lab 2. Exploring" //changes working directory

capture log close //closes anyu log files that are open 

log using lab2.smcl, replace //opens a log file

webuse nhanes2 //download nhanesd dataset from stata website 

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**how many observations are there? 
count
describe
des, short //shorthand 

****
ds //see full variable name
codebook sizplace 

**listing 
list heartatk in 1/10

list sex bmi heartatk in -50/l   //lists last 50 in results window

**versus browse 
browse sex bmi heartatk in -50/l
br //shorthand 

**sort 
gsort- heartatk -age 

br 

list age in 1/3


list age in -10/l


**look at missing heart attacks
tab heartatk, missing


***what percent of females had a heart attack 
tab sex heartatk, row 
tab heartatk sex, col 

tab sex heartatk if age>70, row