MGMT 2340 Section W01 Business Statistics I Instructor: E. Mark Leany contact via Blackboard online.uen.org alternately: [email protected] Describing Data: Displaying and Exploring Data Chapter 4 99
GOALS - Chapter 4 1. Develop and interpret a dot plot . 2. Develop and interpret a stem-and-leaf display . 3. Compute and understand quartiles , decile s , and percentiles . 4. Construct and interpret box plots . 5. Compute and understand the coefficient of skewness . 6. Draw and interpret a scatter diagram . 7.Construct and interpret a contingency table.
(1) The exact identity of each value is lost (2) Difficult to tell how the values within each class are distributed. z One technique that is used to display quantitative information in a condensed form is the stem-and-leaf display. 102 Stem-and-Leaf z Stem-and-leaf display is a statistical technique to present a set of data. Each numerical value is divided into two parts. The leading digit(s) becomes the stem and the trailing digit the leaf. The stems are located along the vertical axis, and the leaf values are stacked against each other along the horizontal axis. z Advantage of the stem-and-leaf display over a frequency distribution - the identity of each observation is not lost. 103
Advertising Spots Example Listed in Table 4–1 is the number of 30-second radio advertising spots purchased by each of the 45 members of the Greater Buffalo Automobile Dealers Association last year. Organize the data into a stem-and-leaf display. Around what values do the number of advertising spots tend to cluster? What is the fewest number of spots purchased by a dealer? The largest number purchased?
- Spring '11
- Standard Deviation