Courses/Computer Science/CPSC 203/CPSC 203 Template/Labs Template/Week 2 - Lab 1: Charts and Visual Design Rules

Introduction
Building on the spreadsheet fundamentals covered in the first two tutorials, today's tutorial will introduce charts and visual design. After completing this module, you should be comfortable in demonstrating the following skills:
 * using Chart Wizard to create the default chart on a data set
 * customizing a chart according to good chart design principles

Additional Reading
Lab 6 page 125 of Fluency Computer Skills Workbook

Use Chart Wizard to do a default chart on a data set

 * A chart can be made easily using the Chart Wizard in Excel. There are a number of chart types (line, bar, pie, etc.) to choose from, and each can be customized, using various options. The data for a chart can either be arranged in rows or columns in a worksheet. It should be noted that some types of charts require particular formatting of the data (consult the the Help function in Excel for specific data arrangement pertaining to a particular chart type). Also, data may be included from several worksheets.
 * More information regarding charts in Excel 2007 can be found here:
 * http://office.microsoft.com/en-us/excel/CH100648161033.aspx
 * The types of charts available in Excel 2007 can be found here:
 * http://office.microsoft.com/en-us/excel/HA012337371033.aspx
 * The following is an example of how to use the Chart Wizard in Excel 2007
 * Step 1
 * Open the following spreadsheet in Excel
 * Step 2
 * In the top menu bar, select 'Insert' using your mouse. You should now see a group of icons labelled 'Charts', under the top menu bar.
 * Step 3
 * Select the data to be included in the chart.
 * Step 4
 * Use your mouse to select the 'Column' chart. A drop down menu should appear showing the different types of column charts available. Select the first type of '2-D Column'.
 * Step 5
 * A new column chart should have been added to your current worksheet. You can move the new chart by clicking-and-dragging it to a new location in the worksheet. Also, notice that a new contextual menu has appeared under the main toolbar. This contextual menu allows for customization to be performed to the chart.

Customize a chart in accordance with good chart design principles

 * There are many elements to a chart. Depending on the type of chart, some elements are displayed by default and others can be added as required. Elements that are not required can be removed. There are many options available to change the look of a chart, by adjusting the various elements. Elements may be moved to other areas of the chart, resized, or reformatted (all dependent on the specific element).
 * For example, such elements include: chart area, plot area, data points/series, horizontal/vertical axis, legend, title, and data label.
 * To customize a chart, you must first select it. A blue rectangle will appear to indicate that the chart has been selected.
 * When a chart is selected, a new contextual menu appears under the main toolbar. In addition to the contextual menu, new items are also added to the main menu bar Chart Tools. There are three items included in the Chart Tools: design, layout, and format.
 * An individual element can also be customized by right-clicking on it, and selecting Format at the bottom of the drop down menu.
 * A chart is automatically adjusted, if changes to the included data occur.
 * More information on formatting charts can be found here:
 * http://office.microsoft.com/en-us/excel/CH100648761033.aspx
 * It is important to remember to evaluate the effectiveness of your chart, after you have made the necessary adjustments. How well does your chart visually depict your data, and communicate the message you would like to send? Sometimes a different chart type is required. A chart can be changed to a different type by selecting Change Chart Type as part of the Design contextual menu under Chart Tools.

Visual Design Rules

 * Visual display of information
 * Bad chart examples
 * Good chart examples
 * Information dashboard
 * Few's 13 mistakes in dashboard design
 * More information can be found in:
 * The Elements of Spreadsheet Style by John M. Nevison

Visual Display of Information
Two Critical Principles in the Visual Display of Information are:
 * Statistical Accuracy (the numbers are the "right" numbers, correctly calculated given the data population/sample you are using).
 * Cognitive Effect (the pattern in the data is made clear as possible to the viewer).

Design Issues in the Visual Display of Information (or the World According to Tufte)
 * 1) Maximize Data Ink -- Ink that directly conveys information about data points
 * 2) Minimize Chart Junk -- All additional glyphs, bells, whistles, 3D effects that do not directly convey data information.
 * 3) Use Small Multiples to deal with Complexity -- Create a basis for comparison in large or complex data sets by creating simple diagrams with common axes or common design elements. Example: http://en.wikipedia.org/wiki/Small_multiple
 * 4) Data Density -- Very large data sets or very complex data sets require us to find visual techniques that maintain the content of the data, but allow us to get a "gestalt" view that can not be obtained from reading a massive data table.
 * 5) Multiple Use -- If possible put visual elements to multiple uses. Data points, could also be numbered reflecting data values. Data glyphs could reflect relationships between the data attributes in frame, and other data attributes.
 * 6) Aesthetics -- The same principles that make various art constructs effective apply also to visualization of data. Example -- use of the "Golden Rectangle" for 2 D displays. http://en.wikipedia.org/wiki/Golden_rectangle

Bad Chart Examples
http://j-walkblog.com/index.php?/weblog/posts/bad_charts/

http://lilt.ilstu.edu/gmklass/pos138/datadisplay/badchart.htm

Good Chart Examples
http://lilt.ilstu.edu/gmklass/pos138/datadisplay/sections/goodcharts.htm

http://www.compassgr.com/sites/mark/index.htm

Information Dashboard
 "Visual Display

 of the most important information needed to achieve one or more objectives 

 which fits entirely on a single computer screen 

 so it can be monitored at a glance" 

.... Stephen Few

Few's 13 Mistakes in Dashboard Design

 * 1) Exceeding the Boundaries of a Single Screen
 * 2) Supplying Inadequate Context for the Data
 * 3) Displaying Excessive Detail or Precision
 * 4) Choosing a Deficient Measure
 * 5) Choosing an Inappropriate Display Media
 * 6) Introducing Meaningless Variety
 * 7) Using Poorly Designed Display Media
 * 8) Encoding Quantitative Data Inaccurately
 * 9) Arranging the Data Poorly
 * 10) Highlighting Important Data Ineffectively or Not at All
 * 11) Cluttering the Display with Useless Decoration
 * 12) Misusing or Overusing Color
 * 13) Designing an Unattractive Visual Display

.... If you understand the 6 principles of Visual Display of Information .... you are much less likely to make these 13 mistakes.

Example
The following example shows successfully more refined charts. The succession shows:
 * removal of the grey background
 * highlighted borders
 * change of scale to roughly Golden Ratio of height and width
 * and finally, the creation of a small multiple display

[[Media:SpShtLec3_IrisDataScattergramAndBasicStatsLookup_20080205.xls]]