library(readxl)
## Warning: package 'readxl' was built under R version 4.1.3
Burgerdata <- read_excel("C:/Users/Lab pc/Downloads/Burgerdata.xlsx")
View(Burgerdata)
attach(Burgerdata)
names(Burgerdata)
## [1] "Weightgain" "Companies"
boxplot(Weightgain ~ Companies)
# Ho - mean weight gain is same for all the companies
aov(Weightgain ~ Companies)
## Call:
## aov(formula = Weightgain ~ Companies)
##
## Terms:
## Companies Residuals
## Sum of Squares 24.2575 90.2280
## Deg. of Freedom 3 16
##
## Residual standard error: 2.374711
## Estimated effects may be unbalanced
Anova1 <- aov(Weightgain ~ Companies)
summary(Anova1)
## Df Sum Sq Mean Sq F value Pr(>F)
## Companies 3 24.26 8.086 1.434 0.27
## Residuals 16 90.23 5.639
attributes(Anova1)
## $names
## [1] "coefficients" "residuals" "effects" "rank"
## [5] "fitted.values" "assign" "qr" "df.residual"
## [9] "contrasts" "xlevels" "call" "terms"
## [13] "model"
##
## $class
## [1] "aov" "lm"
Anova1$coefficients
## (Intercept) CompaniesKFC CompaniesMacDonalds CompaniesWendies
## 5.96 1.74 2.96 2.32
summary(Anova1)
## Df Sum Sq Mean Sq F value Pr(>F)
## Companies 3 24.26 8.086 1.434 0.27
## Residuals 16 90.23 5.639
TukeyHSD(Anova1)
## Tukey multiple comparisons of means
## 95% family-wise confidence level
##
## Fit: aov(formula = Weightgain ~ Companies)
##
## $Companies
## diff lwr upr p adj
## KFC-Burger King 1.74 -2.556962 6.036962 0.6602070
## MacDonalds-Burger King 2.96 -1.336962 7.256962 0.2394801
## Wendies-Burger King 2.32 -1.976962 6.616962 0.4357091
## MacDonalds-KFC 1.22 -3.076962 5.516962 0.8477602
## Wendies-KFC 0.58 -3.716962 4.876962 0.9797373
## Wendies-MacDonalds -0.64 -4.936962 3.656962 0.9731569
plot(TukeyHSD(Anova1))
plot(TukeyHSD(Anova1), las=1)
kruskal.test(Weightgain ~ Companies)
##
## Kruskal-Wallis rank sum test
##
## data: Weightgain by Companies
## Kruskal-Wallis chi-squared = 2.9365, df = 3, p-value = 0.4015