Box and Whisker Plots and Distribution

What is a box and whiskers plot?

• a graphical representation of data using x and y axes.

• a 3D graphical representation of a data set.

• a graphical representation showing the distribution of data by showing the spread of data points, including the median, quartiles, and potential outliers,

What is the minimum value in a data set called in a box plot?

• Lower Extreme

• Lower Quartile

• Median

• Lower Limit

How do I find the Interquartile Range (IQR) on a box plot?

• Add the min. and max.

• Add Q1 and Q3

• Subtract Q1 and Q3

• Subtract the min. and max.

What is the third quartile (Q3) in a box plot?

• The third quartile (Q3) in a box plot is the value that separates the lowest 25% of the data from the highest 75%.

• The third quartile (Q3) in a box plot is the average of the entire dataset.

• The third quartile (Q3) in a box plot is the value that separates the highest 50% of the data from the lowest 50%.

• The third quartile (Q3) in a box plot is the value that separates the highest 25% of the data from the lowest 75%. It is the median of the upper half of the dataset.

Calculate the IQR for the weights (in pounds) of the offensive line on this professional US football team.

307 311 311 313 317 318 318 326 338 353

• The IQR is the difference between the maximum and minimum weights, which is 50 pounds.

• The IQR is the average weight of all offensive linemen, which is 300 pounds.

• The IQR in this example refers to the range of the middle 50% (from Q1 to Q3) of offensive linemen weights, which is 15 pounds.

• The IQR is the sum of the weights of all offensive linemen, which is 1500 pounds.

What is the formula to calculate the lower fence?

• Lower fence = Q1 + 1.5 x IQR

• Lower fence = Q1 - 1.5 x IQR

• Lower fence = Q3 + 1.5 x IQR

• Lower fence = Q3 - 1.5 x IQR

What does point C on the box plot represent?

• First Quartile

• Median

• Third Quartile

• Mean

Which has a higher median?

• Florida

• Texas

9. Employees were asked how many miles they traveled to work each day. The data is shown below in the box plot. Which of the statements best supports the data?

• A. Median = 30, IQR = 20
• B. Median = 35, IQR = 20
• C. Median = 40, IQR = 45
• D. Median = 35, IQR = 45

What is an outlier? What might be the cause of outliers?