Wilcoxon signed- Rank Testi

library(broom)

## Warning: package 'broom' was built under R version 4.5.3

library(ggplot2)
library(dplyr)

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

library(tidyverse)

## Warning: package 'tidyverse' was built under R version 4.5.3

## Warning: package 'lubridate' was built under R version 4.5.3

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## ✔ purrr     1.2.0     ✔ tidyr     1.3.2
## ✔ readr     2.1.6

## ── Conflicts ────────────────────────────────────────── tidyverse_conflicts() ──
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag()    masks stats::lag()
## ℹ Use the conflicted package (<http://conflicted.r-lib.org/>) to force all conflicts to become errors

program_oncesi =c(25,28,30,27,26,29,31,28)
program_sonrasi =c(22,25,27,24,23,26,28,25)

stres_veri<-data.frame(
  id=1:8,
  program_oncesi=c(25,28,30,27,26,29,31,28),
  program_sonrasi=c(22,25,27,24,23,26,28,25)
)
stres_veri

##   id program_oncesi program_sonrasi
## 1  1             25              22
## 2  2             28              25
## 3  3             30              27
## 4  4             27              24
## 5  5             26              23
## 6  6             29              26
## 7  7             31              28
## 8  8             28              25

veri_long <- stres_veri %>% 
  pivot_longer(
    cols=c(program_oncesi,program_sonrasi),
    names_to ="zaman",
    values_to ="stres"
  )
veri_long

## # A tibble: 16 × 3
##       id zaman           stres
##    <int> <chr>           <dbl>
##  1     1 program_oncesi     25
##  2     1 program_sonrasi    22
##  3     2 program_oncesi     28
##  4     2 program_sonrasi    25
##  5     3 program_oncesi     30
##  6     3 program_sonrasi    27
##  7     4 program_oncesi     27
##  8     4 program_sonrasi    24
##  9     5 program_oncesi     26
## 10     5 program_sonrasi    23
## 11     6 program_oncesi     29
## 12     6 program_sonrasi    26
## 13     7 program_oncesi     31
## 14     7 program_sonrasi    28
## 15     8 program_oncesi     28
## 16     8 program_sonrasi    25

         ggplot(veri_long,aes(x=zaman , y =stres , group = id))+
         geom_line(alpha=0.4)+
         geom_point(size=2)+
         labs(title = "program öncesi ve sonrası stres" ,
              x="zaman",
              y="stres")+
        theme_minimal()

ggplot(veri_long,aes(x =zaman, y =stres,fill=zaman))+
  geom_boxplot(alpha=0.6)+
  geom_jitter(width = 0.1, alpha =0.6)+
theme_minimal()

sonuc_stres <-wilcox.test(
  stres_veri$program_oncesi,
  stres_veri$program_sonrasi,
  paired=TRUE
)

## Warning in wilcox.test.default(stres_veri$program_oncesi,
## stres_veri$program_sonrasi, : cannot compute exact p-value with ties

sonuc_stres

## 
##  Wilcoxon signed rank test with continuity correction
## 
## data:  stres_veri$program_oncesi and stres_veri$program_sonrasi
## V = 36, p-value = 0.005962
## alternative hypothesis: true location shift is not equal to 0

wilcoxon Signed-Rank testi sonuçları,psikoeğitim programı sonrasında stres düzeylerinin anlamlı biçimde azakdığını göstermiştir(v=36, p<.0.05).