Bağımsız Örneklem T Testi 2204.2026

library(tidyverse)

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library(lsr)

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

library(car)

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

## Zorunlu paket yükleniyor: carData

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

## 
## Attaching package: 'car'
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library(dplyr)

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))

tail (fare_verisi)

##        grup  sure
## 95  Kontrol 41.06
## 96  Kontrol 46.98
## 97  Kontrol 64.46
## 98  Kontrol 48.06
## 99  Kontrol 47.82
## 100 Kontrol 55.58

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     45.3           8.10
## 2 Kontrol    50     51.9           8.09

fare_verisi %>%
  group_by(grup) %>% 
  summarise(shapiro_p=
              shapiro.test(sure)$p.value)

## # A tibble: 2 × 2
##   grup    shapiro_p
##   <chr>       <dbl>
## 1 Deney       0.834
## 2 Kontrol     0.105

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  0.1414 0.7077
##       98

sonuc<-t.test(sure~grup, data = fare_verisi, var.equal = TRUE)
print(sonuc)

## 
##  Two Sample t-test
## 
## data:  sure by grup
## t = -4.0979, df = 98, p-value = 8.599e-05
## alternative hypothesis: true difference in means between group Deney and group Kontrol is not equal to 0
## 95 percent confidence interval:
##  -9.842763 -3.420037
## sample estimates:
##   mean in group Deney mean in group Kontrol 
##               45.2530               51.8844

cohensD(sure~grup, data = fare_verisi)

## [1] 0.819577

ggplot(fare_verisi,aes(x=grup, y=sure, fill = grup))+
  geom_boxplot(width=0.5, color= "black", alpha=0.7)+
  theme_minimal()+
  scale_fill_manual(values = c("#2E8B57","#CD5C5C"))+
  labs(title = "İlaç (Deney) ve Plasebo(Kontrol) Gruplarının Labirent Tamamlama Sureleri",
       subtitle = "Deney grubunun daha hızlı olduğu (surenin düşük olduğu)görülmektedir.",
       x="Grup", y="Sure (Saniye)")

TESTİ SONUCUNDA İLAÇ VERİLEN DENEY GRUBUNUNLABİRENT TAMAMLAMA SÜRELERİNİN KONTROL GRUBUNA GÖRE ANLAMLI DERECEDE DAHA DÜŞÜK OLDUĞU SAPTANMIŞTIR.