Franklin D. Roosevelt: Life Before the Presidency. Franklin D. Roosevelt: Life Before the Presidency. Franklin Delano Roosevelt was born to James and Sara Roosevelt in 1882. James was a land-owner and businessmen of considerable, but not awesome, wealth from New York.
How to Measure Variability in Statistics. Statisticians use summary measures to describe the amount of variability or spread in a set of data. The most common measures of variability are the range, the interquartile range (IQR), variance, and standard deviation.
Because measures of variability are a form of descriptive statistics, they can only be used to describe the data in our study. They cannot be used to draw conclusions or make inferences that go beyond our data set. Lesson Summary. Variability refers to how spread out a group of data is.