Comparing z-scores
To illustrate the utility of z-scores, let's now look at some housing data, in which the two columns - Bedrooms and Square Feet - are measured very differently.
The z-scores for the "Bedroom" column have already been calculated for you. In this exercise, you will calculate z-scores for the "Square Feet" column using the STANDARDIZE()
function. After that, you will use SUM()
and AVERAGE()
to compare how the distributions are now on the same scale.
As a reminder, the z-score measures how far a value is from the mean using standard deviations.
This exercise is part of the course
Introduction to Statistics in Google Sheets
Exercise instructions
- In cell
I2
, usingSTANDARDIZE()
, pass in the Square Feet ofB2
, then the mean at$E$3
and finally theSTDEVP()
in$F$3
. Drag this formula all the way down to get the entire vector. Remember those$
signs! - In cells
L2
andL3
, useSUM()
to add up the standardized values in columnsH
andI
, respectively. - In cells
M2
andM3
, calculate the mean of the standardized values in columnsH
andI
. Compare the results of the scaled columns.
Hands-on interactive exercise
Turn theory into action with one of our interactive exercises
