1. BUS304 – Data Presentation1 Graphs  Visual presentation of data Pie Chart Bar Chart Line Chart Scatter Chart

2. BUS304 – Data Presentation2 A good graph should  Accurately conveys the information  Grabs the reader’s attention (visually enjoyable)  Complements or demonstrates arguments presented in the text  Is simple and uncluttered  Clearly shows trends or differences in the data  Is visually accurate (i.e. one chart value is 15 and another is 30, then 30 should be twice the size of 15)

3. BUS304 – Data Presentation3 Why use graphs?  Graphs  Are quick and direct  Highlight the most important facts  Facilitate understanding of the data  Can convince readers  Can be easily remembered. Most of the time, creating graphs is more of an art. Bothvisually correct data can create different Most of the time, creating graphs is more of an art. Bothvisually correct data can create different

4. BUS304 – Data Presentation4 Not always good to use graphs  The data are very dispersed  The data are very numerous

5. BUS304 – Data Presentation5 Not always good to use graphs  There are too few data  The data show little variations Sometimes, you may need to try different graphs,and may determine not to use graph in the end. Sometimes, you may need to try different graphs,and may determine not to use graph in the end.

6. BUS304 – Data Presentation6  Usually present categorical and numerical variables grouped in class or intervals  Can be either horizontal of vertical Bar chart category names values

7. BUS304 – Data Presentation7 Create a basic bar chart  Open file “data2.xls”  Create a bar chart using the data in sheet 1  Note that in Excel, the vertical bar chart is called “Column”  Think: do you prefer vertical bars or horizontal bars?

8. BUS304 – Data Presentation8 Other Bar Charts  Side by side bars / stacked bars / 100% stacked bars  when more than one piece of info in one category Create these three charts using data from sheet 1.Compare the difference of the key informationeach chart conveys Legend is importantin those charts Legend is importantin those charts

9. BUS304 – Data Presentation9 Pie Chart  A way of summarizing a set of categorical data  Convenient to present the proportion of each category  It is generally more difficult to convey the actual amount  Works especially when there are not too many categories and the proportions are significantly different from categories.

10. BUS304 – Data Presentation10 Exercise  Use the data in sheet 2 to create a Pie chart. Compare it with the bar chart. Discuss the different information it conveys

11. BUS304 – Data Presentation11 Line Chart  Especially useful in statistics and science. To reflect the trend.  Can draw multiple lines in one graph for comparison. Note: when using Excel to generatea line chart, the X-axis is stillregarded as categorical names.It does not have numerical value Note: when using Excel to generatea line chart, the X-axis is stillregarded as categorical names.It does not have numerical value Exercise: Sheet 1

12. BUS304 – Data Presentation12 Scatter Chart  Mostly used in science and statistics to reflect the sample location.  X-axis and y-axis both have numerical values  Shows data correlations (positive, negative, etc.)

13. BUS304 – Data Presentation13 Observe data correlation from scatter chart  Find the data from sheet 3.  Draw scatter chart using  Sq. Feet as x-axis, Price as y-axis  Age as x-axis, Price as y-axis  No. of bedrooms as x-axis, Price as y-axis  No. of bathrooms as x-axis, Price as y-axis  No. of garages as x-axis, Price as y-axis

14. BUS304 – Data Presentation14 Summary  4 Basic types of charts:  Bar chart  Pie chart  Line chart  Scatter chart  Know how to create a chart from Excel  Know how to read the chart (find a value given a certain condition)  Know the characteristics, and be able to pick the best chart to convey info.