• Principle 1: Show data comparisons.
• Principle 2: Show causality (learning about the evidence).
• Principle 3: Show more than one or two variables (capturing multivariate complexity).
  
  Discussion: Whenever you hear a Tufte seminar you will be immediately introduced to the Minard line chart (surface chart) of Napoleon's Retreat from Moscow during the European War of 1812. When you look at the masterful description, you will note six variables. Minard has calculated the number of troops lost during certain miles of the retreat. Minard provided all the temperatures at certain locations through Russia and Poland that affected the troops. To paraphrase Tufte, Minard captured a multivariate analysis.
  
  Principle 4: Completely integrate word, number, and image.
  
  You are interested in an intellectual architecture. You should supplement page after page of text with appropriate graphics.
  
  Principle 5: Always show documentation, including footnotes.
  
  Discussion: People have to trust your data. People want to know where you found the information. The problem of missing data can create less trust. Your documentation adds to your quality control.
  
  Principle 6: Get better content (quality, relevance, integrity of your content).
  
  Discussion: You cannot risk poor content when you present data. If your numbers are not sufficient, get better numbers. You don't want Chartjunk. It is interesting that nowhere on Minard's surface chart does Napoleon's name appear. The chart was meant to honor the fallen Frenchmen who fought for Napoleon.
  
  Principle 7: Try to show information adjacent in space (rather than stacked in time).
  
  Discussion: If you ever looked at Galileo's (Earth moved around the Sun) original drawings of sunspots, you would see immediately what Tufte meant by "adjacent in space." If we took a special effect mechanism and ran through each sighting of sunspots, we notice immediately that spacing of the sunspots catches our eyes. It was if we had a time-lapse photography of all of Galileo's sunspot observations. Contrast that image with the computer screen with too many applications as icons stacked in time. The eye becomes weary.
  
  Principle 8: Use small multiples (easy on your viewers).
  
  Discussion: Bar charts, for example, act as information architecture. With small multiples on these charts we can demonstrate mastery of detail. As you know, I always ask you to label the axes, both horizontal and vertical. You may need a legend. By labeling every appropriate multiple, you do not run the risk of someone accusing you of evidence selection. You need to understand the credibility of the information.

Selection of Charts Requires Sharp Analysis

You have to make a selection first about whether you will use a pie, bar, line, surface, or flowchart. Once that decision has been made and you have determined the chart's purpose, you are ready to choose a question from your survey or interview guide. You should not choose too much data for the chart presentation.

A student was recently faced with an interview guide. What questions were most important to present what the apartment complex should do to increase tenancy? The student had to examine his problem question as well as his purpose. Eventually, the student decided that the use of media recommended by the tenants and the manager might be the most important information to present. The student could use a horizontal bar chart (bar chart) to present the data with the vertical axis showing the different media and the horizontal axis showing the number of respondents for each kind of media. Here's how the student arrived at all these decisions:

• Determine the chart's purpose.
• Determine the categories (by you) the interviewees talked about.
• Arrive at a set list of categories.
• Determine how to create the value and category axis for a program, such as Excel.
• Plot the appropriate numbers with an appropriate chart from Excel, for example.
• Conceive title for chart. Make sure you write a talking caption.
• Pick out the most important bar or slice for writing your title.
• Conceive a conclusion for the title.

Choosing Charts Causes Concern

In the latest Style Guide for Business and Technical Communication from Franklin- Covey, a well-known scheduling book and time management company providing seminar services, the issue of which chart for which occasion occurred. You may also recognize Covey as the author of several books on Effective Habits for individuals and families. The book is devoted to all kind of business communication situations, but the chart section of the reference was particularly strong. We can classify certain charts as to their uses. First, the pie charts are considered:

Advantages and Disadvantages
Comparison and Contrast
Decisions and Alternatives
Costs
Trends

This list suggests you should consider a pie chart when you are expressing the previous items. For example, 100 percent of some costs might necessitate a pie chart. You could also use a line chart, depending on your preference and what you wanted to show.

You could compare or contrast certain slices of the pie and percentages. Think of an example, such as percentage cost to run each department of a retail store. You comparison and contrast works well in that case.

For line chart selection you have a number of alternatives. The uses include:

Chronology
Costs
Trends
Decisions and Alternatives
Comparison and Contrasts

Chronology particularly interested me in this list. You see all the time the chronology of certain stock transactions in the newspaper. You see the history of the stock as well as the ups and downs of the market prices. Can you think of a line chart that would show decisions and alternatives?

Pie Charts Can Tell a Good Tale

One semester a student did a fascinating report on store tastings for a particular chain store. I did not know anything about store tastings. Apparently, store tastings occur when the employees are asked to sample different beverages or other merchandise before the product is made available to the public. According to the student, a store tasting "provides a time set aside for employees to either sample new products entering the store, or items that have not been sampled before to help increase familiarity about the products." Therefore, the student was interested in presenting data about whether employees engaged in a free for all by taking a free lunch instead of tasting the products. Out of that desire to present grew a pie chart.

As we remember a pie chart, you need to have 100 percent of something. You usually deal with percentages in a pie chart. You try to avoid more than six segments or slices in the pie for readability. The student presented data about attitudes toward the store tastings. The student calculated the percentages of responses for three major categories: (1)Store Tastings Are a Free for All; (2)Store Tastings Are Sometimes a Free for All; and (3)Store Tastings Are Not a Free for All. The student discovered that the largest percentages occurred in the first two categories. Even though the student only had 13 respondents or employees, the percentages made the point quickly. That is what you must do with your chart selected. Make your point quickly.

Explanation Tie-In Requires Analysis

In the newly revised analytical report memo you are asked to provide an explanation tie-in for the table and figure. You are technically writing part of the Considerations section of the memo. You are doing more than saying the table and chart contain data. Your explanation in paragraph memo form with captions means you tell the significance of the numbers. You talk about percentages and averages. Your work will probably encompass close to a page of single-spaced keyboarding. You don't have to report every single number. However, you do not let the table or chart speak for themselves.

Actual Paragraphs Show Handling of Tie-In

I suspect it would be helpful to see some actual paragraphs from a report and how the student handled part of the Considerations. In the report you are seeing the student surveying elementary school youngsters about their languages used and homework help obtained. You see one of the paragraphs called the explanation tie-in:

Attachment B, Table 1, describes people helping the sample students with their homework. The results show that 12 students (46 percent), the largest number, do not obtain assistance with their homework by any member of their home. They do homework by themselves. Five students (15 percent) are assisted by a third relative (aunt, uncle, or cousin). Three students (12 percent) obtain help from their siblings (brothers, sisters, or both).

In the second illustration we see explanation tie-in for charts, especially a pie chart. The student is trying to find out how to improve training in an investment banking firm. We will call the firm HEI. In the pie chart the student report writer had given the statistics of Strongly familiar (one slice), 23 percent, and Somewhat familiar (another slice or segment), 31 percent. From this pie chart the student wrote the following as part of the Considerations:

Figure 1 (Attachment B) presents a graphic display of the answers given to the HEI operations question. Out of the 13 people surveyed, only seven respondents (54 percent) were able to state they had some familiarity with HEI. The survey further revealed that some employees are not even aware that other key agencies in the settlement process exist.

Think about: Did you spot that 54 percent was arrived at by adding 23 and 31 percents respectively? It is always wise to combine numbers where appropriate in pie and horizontal bar charts. If we looked at the rest of the pie chart, we would see Just get-by, 23 percent, and Don't know, 23 percent. Did you notice the writer did not have to repeat the question to present the data? The report writer simply stated the "HEI operations question" and let the reader refer to the Attachments for more information about the exact wording of the question.

Exercise: Draw the chart you have just read about.

Tables and Charts Create Their Own Problems

In the analytical report we place, for the most part, the tables and charts in the Attachments. Each table has its own table number and table title written this way:

TABLE 1
STORE TASTING PREPARATION SURVEY FOR EMPLOYEES

For charts you should use the Figure number and the Figure title. The figure title must be a talking caption. The figure number and figure title must be centered over the visual. Let's take an example:

FIGURE 1
CUSTOMERS WANT CIGARETTE VENDING MACHINE REMOVED

What you do in a figure is find some piece of data that stands out. That might be a pie chart, a line chart, or a bar chart. You make that piece of data your title. You avoid saying some of the following phrases:

SURVEY IDENTIFIES PROBLEMS
DATA SHOWS AN INCREASE
CHART SHOWS AN INVESTMENT OPPORTUNITY

These previous, vague titles do not let the reader know what is going on. You need to have your caption "talk" to the reader.

Look Out for Quantitative and Qualitative Data

Tables require columnar presentation of data. Often, selecting specific questions or a whole range of interview of questionnaire questions will give you the data for a table. You may even build a quantitative data table from the interviews. You simply conceive the categories and place in the data in some workable fashion with the columns and rows. For example, columns for advantages and disadvantages of some particular plan may be a helpful way to present the qualitative data, categories you conceived from open-ended questions..

Qualitative Data Present Choices

Perhaps an actual example of a student facing a dilemma with presenting data will further explain the use of qualitative data. The student's report originally dealt with cash flow and advertising's impact. He interviewed two major department heads, including the customer service representative who gave him superb data about suggested solutions to the cash flow problem. The student did not have quantitative data; he had two interviews. Then, a light bulb dawned in the student's mind. Why couldn't he set up vertical columns headed "Department," "Problem," and "Suggested Solution"?

The student made choices. He knew management would appreciate a capsule form of the data shown in a qualitative data table. The customer representative provided particularly good data for presenting in the table. The student could place "n=2" after the title in the table. In quantitative tables, such as numbers and percentages, you may want to provide each question on the left side of the table. You may shorten or paraphrase the question to accommodate the space. Then, your columns can be numbers, percentages, and total. Never forget to include a total column.

Don't forget that every table and figure should have "n=25 or number of respondents" placed in parentheses immediately after the table title. You need to clarify how many people responded. The reader should not be left to guess how many percentages or have to calculate the appropriate statistics.

Chart Assignment Aids Growth (Makeup)

In class we looked at five different problems and the charts that would satisfy each situation. You are asked to first say whether the chart should be component, item, time series, frequency distribution, or correlation. Use these exact words in explaining the chart. Then, rough out the chart by labeling Y and X axis and a title for each chart. Remember to use different kinds of plot lines for correlation (if appropriate) than for a horizontal bar chart. The exercises now follow:

• Sales are forecast to increase over the next 10 years.
• The largest number of employees earns between $30,000 and $35,000.
• In September, the turnover rates for the six divisions were about the same.
• The sales manager spends only 15 percent of the time in the field.
• Size of merit increases is not related to tenure.
• Region C ranks last in productivity.

Tables and Charts Assignment Needs Clarification

Certain students over the semester have asked about the tables and charts assignment with the Tufte criteria. I have chosen selected paragraphs from previous students' memos to talk about clarification:

Quantitative Table Needs Investigation

The table shows heads for the rows and columns. The figures given are in percentages and in dollars in the first item in each column. Percentages are given for the first column and dollar signs for the next two columns. The title clearly states the main point. The graphic shows chronological order from 4.25% to 8.25%. It compares different interest rates, monthly payments and total costs. A source is shown at the bottom of the graphic. The research was performed by Times Research.

The table shows exact figures, and serves its purpose. However, the table needs a line between interest rate and monthly payment.

Think about: You are doing content thinking, not analysis thinking. We don't care what the table shows. We are interested in Tufte's principles.

What evidence is shown through footnotes and text that suggest you can trust the data?

In this case I looked at three variables, interest rate, monthly payment, and total cost. How clearly were those variables presented? Can you find the information you need to discover? How?

Principle 4 talks about integration of number, image, and word. As you look at the table, how effectively were those three elements integrated into the visual? How do you know? Give some specifics.

Think about: What kind of data comparisons are shown? Are the figures arranged in such a way that a clear presentation is given?

Think about: How could better content be achieved in the table or the graph?

Principle 8 talks about ease of reading. How clear were the numbers or the figures in understanding the visual? Did you find the table or the chart appealing to the eye? How do you know? Give some specific examples.

We Drown in Numbers

Charles Osgood, now narrator of Sunday Morning on CBS featured a special Osgood File about how we are drowning in numbers. We have license permit numbers and PIN numbers. Osgood asks us if we are tired of numbers. We have social security numbers and tax numbers. Numbers define and locate us. You have an access code. You have area codes and telephone numbers to remember. You have so many numbers to remember.

Is the day coming when we will talk in our language only in digits? Will the keypad replace the keyboard? What will the conversation of the future sound like? The computer has achieved the triumph of numbers. These questions are worth pondering.