[M]-Mean.md

Mean

Preparation Code

# Functions
library(dplyr)

# Sample Data
library(vcd)
A <- Arthritis

Actual Code

Sample Task 1

Compute mean age.

mean(A$Age)

Sample Task 2

Compute mean age for each gender.

A %>% group_by(Sex) %>% summarise(Mean = mean(Age))

Sample Task 3

Compute mean age, grouping primarily by mode of treatment, and secondarily by gender.

A %>% group_by(Treatment, Sex) %>% summarise(Mean = mean(Age))

Sample Task 4

Excluding the most extreme 10% of age data (5% on the lower tail and 5% on the upper tail), compute mean age.

mean(A$Age, trim = 0.05)

Sample Task 5

Excluding the most extreme 10% of age data (5% on the lower tail and 5% on the upper tail), compute mean age for each gender.

A %>% group_by(Sex) %>% summarise(Mean = mean(Age, trim = 0.05))