distance

A clinical dataset of $100$ individuals. For each individual, we have the measurements of blood pressure, blood glucose level, HDL level, red blood cell count. The range of the four variables among $100$ individuals are given by

Blood pressure: $100$ to $140mmHg($mean $=120,sd=8)$

Glucose: $80$ to mean $=100,$ sd $=8$

$-$HDL: $35$ to $65m\frac{g}{d}L($ mean $=50,$ sd $=5)$

RBC count: $3,500,000$ to $6,000,000$ cells $\frac{?}{mcL}($mean $=$

$4,500,000,5d=700,000)$

We use the Euclidean distance to measure how similar the measurements of these four individuals are

dist$($toy$,$ method$=$"euclidean", diag$=$TRUE$)$

## subjectA subjectB subjectC

## subjectA $0$

## subjectB $1000000$ o

$\frac{?}{?}\frac{\text{\#}}{\text{\#}}$ subjectC $500000,500000,0$

$\frac{?}{?}\frac{\text{\#}}{\text{\#}}$ subjectD $510000,490000,10000$

Subject $C$ and Subject B

oint

abover from the distance matrix is reliable to make conclusion about the differences bet reen subjects.

True

False

$1$ point

Which R$-$function we could use to standardize our data?

$$ mean$()$

summary$()$

standard$()$

scale$()$

The below code is used to standardize our data for $(i$ in $1$: $100)\{$ toy$[,$ i toy $]$mean$[$i$])/$sd$[$i$]\}$

After we standardized our dataset, what is the variance of the distribution of HDL level?