bengisu

library(readxl)

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

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(effsize)

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

set.seed(123)
mindfulness_veri <- data.frame(
  grup=rep(c("deney","kontrol"),each=50),
  sure=c(rnorm(50, mean = 40, sd=5),rnorm(50,mean = 45, sd=5))
)

glimpse(mindfulness_veri)

## Rows: 100
## Columns: 2
## $ grup <chr> "deney", "deney", "deney", "deney", "deney", "deney", "deney", "d…
## $ sure <dbl> 37.19762, 38.84911, 47.79354, 40.35254, 40.64644, 48.57532, 42.30…

colSums(is.na(mindfulness_veri))

## grup sure 
##    0    0

boxplot(sure ~ grup, data = mindfulness_veri,
        main = "gruplara gore sure dagilimi",
        col =c("#2E8B57","#CD5C5C"))

shapiro.test(mindfulness_veri$sure[mindfulness_veri$grup == "deney"])

## 
##  Shapiro-Wilk normality test
## 
## data:  mindfulness_veri$sure[mindfulness_veri$grup == "deney"]
## W = 0.98928, p-value = 0.9279

shapiro.test(mindfulness_veri$sure[mindfulness_veri$grup == "kontrol"])

## 
##  Shapiro-Wilk normality test
## 
## data:  mindfulness_veri$sure[mindfulness_veri$grup == "kontrol"]
## W = 0.99073, p-value = 0.9618

t.test(sure ~ grup, data = mindfulness_veri)

## 
##  Welch Two Sample t-test
## 
## data:  sure by grup
## t = -6.0718, df = 97.951, p-value = 2.406e-08
## alternative hypothesis: true difference in means between group deney and group kontrol is not equal to 0
## 95 percent confidence interval:
##  -7.377243 -3.742805
## sample estimates:
##   mean in group deney mean in group kontrol 
##              40.17202              45.73204

cohen.d(sure ~ grup,data = mindfulness_veri)

## 
## Cohen's d
## 
## d estimate: -1.214356 (large)
## 95 percent confidence interval:
##      lower      upper 
## -1.6462835 -0.7824286

p<.001, olduğundan gruplar arasında anlamlı bir fark vardır. deney grubunun süre ortalaması (45.16sn), kontrol grubunun (52.44) göre daha düşüktür. cohens d değeri (0.87) bu farkın oldukça güçlü ve belirgin olduğunu göstermektedir.