1. Assessing Normality When is the data Normal enough?

2. Use the 68-95-99.7 Rule 1) Plot the data and check for the shape to be……. 2) Determine if ____ % of the data is within 1 standard deviation 3) Determine if 95% of the data is within ___ standard deviations 4) Determine if ____ % of the data is within ____ standard deviations

3. Normal Probability Plot  X-axis is the data scale  Y-axis is the z-score scale  All data is converted to its z-score and plotted as (data, z-score)  Data should appear linear if it is Normal

4. Shape from Normal Probability Plot  Symmetric = Linear  Skewed Right = few large values, so large x-values will fall to the right of the line  Skewed left = few small values, so small values will fall to the left of the line

5. Refrigerator Space The following is a sample of 36 side-by-side refrigerators and their capacity (in cubic feet). Are the data close to Normal? 12.913.714.114.214.5 14.614.715.115.2 15.3 15.5 15.6 15.816.0 16.2 16.316.416.5 16.6 16.817.0 17.217.4 17.9 18.4 ENTER IN YOUR CALC IN L1

6. My Calculator Example On the Emulator