* do-file for Extra Exercise 22
version 18 /* works also with versions 13-17 */

import delimited "R:\Chapter 10\ex10_033.csv"
pwcorr retinol crp, sig
spearman retinol crp
* manual calculation of Spearman's rho, for demonstration purposes
egen rankret=rank(retinol)
egen rankcrp=rank(crp)
pwcorr rankret rankcrp, sig

import delimited "R:\Chapter 2\ex02_002.csv"
* from Exercise 10.7
pwcorr round1 round2, sig
pwcorr round1 round2 if player~=8, sig
pwcorr round1 round2 if player~=7 & player~=8, sig
* Spearman's rank correlation
spearman round1 round2
spearman round1 round2 if player~=8
spearman round1 round2 if player~=7 & player~=8