Statistics
Numerical Measures of Center
February 5, 2009
Reading Quiz
1. The two basic questions about a distribution that tables and graphs help us answer are:
2. Describe the shape of the distributions represented in the histograms on the top line of
the back of this page.
Outline
1. Questions on the homework.
2. Options in CrunchIt.
3. Measuring center: the mean (x̄)
4. Measuring center: the median (M )
5. What do the mean and the median tell us?
6. The relative location of mean and median in symmetric and skewed distributions.
7. The median is resistant to outliers while the mean is not.
Statistics
Numerical Measures of Center
Duration of Old Faithful Eruptions
MMs per bag
February 5, 2009
Visitor scores in 2003 games