x1 <- rnorm(10, mean=100, sd=15)
x1
t.test(x1, mu=95)

1. What is the std error value?
2. What if you have a sample with a large size?
   • How do you get your se?

ster <- sd(x1)/sqrt(length(x1))
difx <- mean(x1)-95
tvalue <- difx/ster

difx
ster
tvalue

x2 <- rnorm(100, mean=100, sd=15)
head(x2)
tail(x2)
t.test(x2, mu=95)

ster <- sd(x2)/sqrt(length(x2))
difx <- mean(x2)-95
tvalue <- difx/ster

difx
ster
tvalue

mtcars
mtcars$mpg
mtcars$am

t.test(mtcars$mpg~mtcars$am)

a = c(65, 78, 88, 55, 48, 95, 66, 57, 79, 81)

t.test(a, mu=60)