Bupa

install.packages(“hms”) install.packages(“car”) install.packages(“DescTools”) install.packages(“MASS”) library(DescTools) library(MASS) library(hms) library(car)

# Load data
bupa <- read.csv("/Users/nupoor/Documents/MSDA/DA- Algo/Week 2 exercise/bupa.csv")
head(bupa)

  mcv alkphos drinkgroup
1  85      92          1
2  85      64          1
3  86      54          1
4  91      78          1
5  87      70          1
6  98      55          1

str(bupa)

'data.frame':   345 obs. of  3 variables:
 $ mcv       : int  85 85 86 91 87 98 88 88 92 90 ...
 $ alkphos   : int  92 64 54 78 70 55 62 67 54 60 ...
 $ drinkgroup: int  1 1 1 1 1 1 1 1 1 1 ...

# Convert drinkgroup to factor
bupa$drinkgroup = as.factor(bupa$drinkgroup)

# Summary of drinkgroup
table(bupa$drinkgroup)

  1   2   3   4   5 
117  52  88  67  21 

# ANOVA analysis for mcv ~ drinkgroup
aov.bupa = aov(mcv ~ drinkgroup, data = bupa)
summary(aov.bupa)

             Df Sum Sq Mean Sq F value   Pr(>F)    
drinkgroup    4    733  183.29   10.26 7.43e-08 ***
Residuals   340   6073   17.86                     
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

### Levene's Test ### Following error in running Levene's Test hence difficulty in rendering even after using 'car'and 'hms'-
### processing file: Bupa.qmd
### Quitting from lines 46-48 [unnamed-chunk-6] (Bupa.qmd)
### Error in `LeveneTest()`:
### ! could not find function "LeveneTest"
###Execution halted
### LeveneTest(aov.bupa)

# Diagnostic plots
par(mfrow = c(2, 2))
plot(aov.bupa)

par(mfrow = c(1, 1))
plot(aov.bupa, 1)

plot(aov.bupa, 2)

# Linear regression model for mcv ~ drinkgroup
lm.res_bupa = lm(mcv ~ drinkgroup, data = bupa)
anova(lm.res_bupa)

Analysis of Variance Table

Response: mcv
            Df Sum Sq Mean Sq F value    Pr(>F)    
drinkgroup   4  733.2 183.294  10.262 7.429e-08 ***
Residuals  340 6073.1  17.862                      
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

summary(lm.res_bupa)$r.squared

[1] 0.1077214

## ANOVA analysis for alkphos ~ drinkgroup
aov.bupa_alkphos = aov(alkphos ~ drinkgroup, data = bupa)
## LeveneTest(aov.bupa_alkphos)

# Diagnostic plots
par(mfrow = c(2, 2))
plot(aov.bupa_alkphos)

par(mfrow = c(1, 1))
plot(aov.bupa_alkphos, 1)

plot(aov.bupa_alkphos, 2)

# Linear regression model for alkphos ~ drinkgroup
lm.res_bupa_alkphos = lm(alkphos ~ drinkgroup, data = bupa)
anova(lm.res_bupa_alkphos)

Analysis of Variance Table

Response: alkphos
            Df Sum Sq Mean Sq F value  Pr(>F)   
drinkgroup   4   4946 1236.41  3.7921 0.00495 **
Residuals  340 110858  326.05                   
---
Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

summary(lm.res_bupa_alkphos)$r.squared

[1] 0.04270721

# Post-hoc tests
#ScheffeTest(aov.bupa)
#ScheffeTest(aov.bupa_alkphos)