Exercises

Author(s)

Prerequisites

1. When is a log transformation valuable?

2. If the arithmetic mean of log₁₀ transformed data were 3, what would be the geometric mean?

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

4. What value of λ in Tukey's ladder decreases skew the most?

5. What value of λ in Tukey's ladder increases skew the most?

6. In the ADHD case study, transform the data in the placebo condition (D0) with λ's of .5, 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?

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