* Import data from an Excel file
import excel "C:\Users\HuKang\Stata\workshop\PST_LN_status.xlsx", sheet("data") firstrow
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* Because data file is in the current working directory, the path is not needed
clear
import excel "PST_LN_status.xlsx", sheet("data") firstrow

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* Import data from a Tab delimited text file
clear
import delimited "C:\Users\HuKang\Stata\workshop\PST_LN_status.txt"
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* checking lesion data
list Lesion Size1 if Lesion == "T1"
list Lesion Size1 if Lesion == "T2"
list Lesion Size1 if Lesion == "T3"

by Lesion, sort: list Lesion Size1

* describe data content with codebook

codebook Nodes NodeStatus

codebook

* summarizing data

summarize Size1 Size2 Size3
sum Size1 Size2 Size3, detail

* graphing data
* boxplots
graph box Size1 Size2

graph box Size1 Size2, over (Lesion)

graph box Size2, over (NodeStatus)


* two-way scatter (correlation) plot

twoway (scatter Size3 Size2)

twoway (scatter Size3 Size2) (lfit Size3 Size2)

* Statistical analysis

* Example 1

ttest Size1==Size2 if Lesion == "T1"
ttest Size1==Size2 if Lesion == "T2"
ttest Size1==Size2 if Lesion == "T3"

by Lesion, sort: ttest Size1==Size2

* Statistical analysis

oneway Size2 NodeStatus, tabulate