Comparing Distributions

Question 1

(How & what) Comparing Distributions

Answer 1

Using histograms or stem-and-leaf displays to compare this, consider their: shape, center, and spread.

Question 2

Comparing Boxplots

Answer 2

When comparing groups using this type of display consider: shapes, medians, IQRs, and outliers.

Question 3

Timeplot

Answer 3

This is a way to display data that change over time by connecting successive values with lines to show trends more clearly; adding a smooth curve can show long-term patterns.

Question 4

Re-express the data

Answer 4

Apply a simple function (such as logarithm or square root) to make the skewed distribution more symmetric.

Question 5

Transform the data

Answer 5

Apply a simple function (such as logarithm or square root) to make the skewed distribution more symmetric (also called re-express).

Question 6

Moving Average (when & how)

Answer 6

Used to smooth a timeplot by finding the average values in an interval called a “window”.

Question 7

Exponential Smoothing

Answer 7

This strategy can be used to predict the future by giving more weight to values in the recent past and less weight to values in the distant past.