# OMIS 2010 Chapter Notes - Chapter 1-4: Univariate, Skewness, Unimodality

## Document Summary

Make a table that lists each person, his number or letter: count the number of times that each combination occurs, see if there is a relationship convert frequencies in each row/column to relative frequencies (divide each row by the total) *totals may not equal 1 because of rounding a graph depicting the relationship b/w 2 nominal variables will look like: if the variables are unrelated, the patterns in each section will be the same, if some relationship exists some will differ from others. The linear correlation looks at the degree in which changes in one variable are/ tend to be proportional to changes in another: a perfect positive (or direct) linear correlation occurs if y increases at a constant rate as x increases, a perfect negative (or inverse) linear correlation is one in which y decreases at a constant rate as x increases.