# 16.E: Transformations (Exercises)

## General Questions

### Q1

When is a log transformation valuable?

### Q2

If the arithmetic mean of \(\log_{10}\) transformed data were \(3\), what would be the geometric mean?

### Q3

Using Tukey's ladder of transformation, transform the following data using a \(λ\) of \(0.5: 9, 16, 25\)

### Q4

What value of \(λ\) in Tukey's ladder decreases skew the most?

### Q5

What value of \(λ\) in Tukey's ladder increases skew the most?

## Question from Case Study

### Q6

In the ADHD case study, transform the data in the placebo condition (\(D0\)) with \(λ's\) of \(0.5\), \(0\), \(-0.5\), and \(-1\). How does the skew in each of these compare to the skew in the raw data. Which transformation leads to the least skew?

## Contributor

Online Statistics Education: A Multimedia Course of Study (http://onlinestatbook.com/). Project Leader: David M. Lane, Rice University.