1. 2.2 Measures of Central Tendency Skewing distributions

2. Distributions The way mean and median compare tells you about the distribution Symmetric distributions: mean and median are roughly the same “roughly the same” depends on spread of data – next class Mean = 0.09 Median = 0.12

3. Skewed Distributions Mean and median are not the same The mean is skewed by the outlying data Left-skewed –mean < median Right-skewed –mean > median

4. Examples of Skewed Distributions mean = -1.08 median = -1.98 mean = 1.84 median = 2.40 mean > median Right-skewed mean < median Left-skewed

5. Using Fathom to calculate mode Create a measure called mode Use the following formula: mean(x, rank(x) – uniquerank(x) = max(rank(x) – uniquerank(x))) Why is there no mode function in Fathom/Excel? Good question…