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## R code to accompany the textbook
## Statistics: The Art & Science of Learning from Data
## by A. Agresti, C. Franklin and B. Klingenberg
## 5th Edition, Pearson 2021
## Web: ArtofStat.com
## Copyright: Bernhard Klingenberg
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###  Chapter 15  ###
###  Example 3   ###
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## Wilcoxon Test: Finding Ranks (Large Sample) ##
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# Reading in data:
reactionTimes <- read.csv(file='https://raw.githubusercontent.com/artofstat/data/master/Chapter15/reaction_time_long.csv')
head(reactionTimes)

# To assign ranks to the values
reactionTimes$Rank <- rank(reactionTimes$response)

# To subset the data
phoneRanks <- subset(reactionTimes, group == 'phone')$Rank
controlRanks <- subset(reactionTimes, group == 'control')$Rank

# To perform a Wilcoxon test
wilcox.test(phoneRanks, controlRanks)