An archive the questions from Mark's Summer 2018 Stat 185.

CDC BMIs

mark

The data for our BMI problem on our in class work sheet was obtained by the following code:

cdc_data = read.csv('https://www.marksmath.org/data/cdc.csv')
men = subset(cdc_data, gender=='m')
len = length(men$weight)

set.seed(1)
n = 25
samp = sample(1:len,n)
weights = men[samp,]$weight
heights = men[samp,]$height
bmis = 703*weights/heights^2
xbar = mean(bmis)
se = sd(bmis)/sqrt(n)
c(xbar,se)

# Out:
# [1] 28.094044  1.027298

After executing that code, run a t-test using the following code:

t.test(bmis, mu=25, alternative = "greater")

What relationship do you see between the output of this command and your computations on the worksheet?