Chapter 11 Displaying Distributions with Graphs

Turning Quantitative Data Into Information u Shape of the data u Center of the data u Spread of the data (Variability)

Weight Data STAT 051 Class Survey -- Spring, 1997 – University of Vermont

Weight Data: Frequency Table * Left endpoint is included in the group, right endpoint is not.

Weight Data: Histogram Weight * Left endpoint is included in the group, right endpoint is not.

Shape of the Data u Symmetric –bell shaped –other symmetric shapes u Asymmetric –skewed to the right –skewed to the left u Unimodal, bimodal, multimodal

Symmetric Distributions Bell-Shaped

Symmetric Distributions Mound-Shaped

Symmetric Distributions Uniform

Asymmetric Distributions Skewed to the Left

Asymmetric Distributions Skewed to the Right

Outliers u Extreme values, far from the rest of the data. u May occur naturally u May occur due to error in recording u May occur due to error in measuring u Observational unit may be fundamentally different

Number of Books Read for Pleasure