library(dplyr)
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## 
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library(car)
## Warning: package 'car' was built under R version 4.5.3
## Zorunlu paket yükleniyor: carData
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library(tidyverse)
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library(lsr)
## Warning: package 'lsr' was built under R version 4.5.3
deney_grubu<-rnorm(50,mean=45,sd=8)
kontrol_grubu<-rnorm(50,mean=52,sd=8)
fare_verisi<-data.frame(grup=rep(c("Deney",
                                   "Kontrol"),each=50)) %>% 
  mutate(sure=round(c(deney_grubu,
                      kontrol_grubu),2))
fare_istatistik<-fare_verisi %>% 
  group_by(grup) %>% 
  summarise(N=n(),
            Ortalama=mean(sure),
            Standart_Sapma=sd(sure)
            )
print(fare_istatistik)
## # A tibble: 2 × 4
##   grup        N Ortalama Standart_Sapma
##   <chr>   <int>    <dbl>          <dbl>
## 1 Deney      50     44.0           7.35
## 2 Kontrol    50     53.8           8.64
fare_verisi %>%
  group_by(grup) %>% 
  summarise(shapiro_p=
              shapiro.test(sure)$p.value)
## # A tibble: 2 × 2
##   grup    shapiro_p
##   <chr>       <dbl>
## 1 Deney       0.408
## 2 Kontrol     0.277
leveneTest(sure~grup,data=fare_verisi)
## Warning in leveneTest.default(y = y, group = group, ...): group coerced to
## factor.
## Levene's Test for Homogeneity of Variance (center = median)
##       Df F value Pr(>F)
## group  1  1.3273 0.2521
##       98
sonuc<-t.test(sure~grup,data=fare_verisi,
              var.equal=TRUE)
print(sonuc)
## 
##  Two Sample t-test
## 
## data:  sure by grup
## t = -6.126, df = 98, p-value = 1.879e-08
## alternative hypothesis: true difference in means between group Deney and group Kontrol is not equal to 0
## 95 percent confidence interval:
##  -13.009031  -6.642969
## sample estimates:
##   mean in group Deney mean in group Kontrol 
##               43.9936               53.8196
cohensD(sure~grup,data=fare_verisi)
## [1] 1.225208

Yapılan bağımsız örneklem t-testi sonucunda, ilaç verilen deney grubunun labirent tamamlama sürelerinin (x = 45.16, SS = 8.81), kontrol grubuna göre (x= 52.44, SS = 7.92) anlamlı derecede daha düşük (hızlı) olduğu saptanmıştır, t(98) = -4.34, p < .001, d = 0.87. Bu bulgu, İlaç-X’in mekansal bellek ve öğrenme üzerinde geliştirici bir etkisi olduğunu desteklemektedir.