I am indebted to former and current students for many of the ideas for this web site.
Suppose you face a dilemma about where to begin with your tables and charts. You have been asked to look for significant data. What are significant data? Look for questions where the answers will make the point in your report. Let's say you have written the following question on your survey: "Do you experience regularly scheduled meetings (weekly, monthly, and so forth)?" This question would make a good table of data. You could place columns for the "Yes," "No," and "No opinion" responses and the numbers of managers, assistant managers, and office employees who answered in each case. The numbers could be placed in rows. Your horizontal labels will become the types of respondents, such as managers. Now, you have the beginnings of a table. You took one important question and made it into a table.
One of my students sharply saw what could become a table. He asked a question about number of semesters students attended at a particular institution. He then set up columns for 1-2, 3-4, and 5-6 and so forth for the number of semesters. He created a banner head for Semesters. Then, in the section for Stub Head he placed the paraphrased question. He tallied the number of responses across for each semester. This report writer had the beginnings of an excellent table.
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:
Advantages and DisadvantagesThis 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.
Comparison and Contrast
Decisions and Alternatives
ChronologyChronology 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?
Decisions and Alternatives
Comparison and Contrasts
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.
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.
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.
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:
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:
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.
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..
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.
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:
To: Dr. G. Jay Christensen From: Gustave Gomez firstname.lastname@example.org Date: Current Subject: EVALUATION OF TABLES AND CHARTSVisuals Receive Attention
This memo is written to critique and analyze two tables and two charts. Table 1 in Attachment A presents a qualitative explanation of seven various types of automotive fuel cells. Table 2 in Attachment B contains a breakdown of the top ten box office earners. All elements of the daily weather of North America are illustrated in Attachment C. Attachment D is a bar chart demonstrating the costs associated with ownership of a Mercedes-Benz E65 AMG. Each of these illustrations attempts to conquer the difficult task of clearly presenting an explanation through a chart or table.Illustrations Show Comparison
Qualitative Table 1 (Attachment A)presents various data being compared. This table sufficiently compares data by comparing and explaining five facets of seven various options. Advantages are provided alongside disadvantages in a non-biased manner. The table clearly and understandably compares the data found within the research. The creator of the table successfully transfers understanding of the topic onto the reader. Table 2 (Attachment B)also provides data comparisons on an array of important information. The data shown in the table cover every bit of information a reader would expect to see in such a table. The illustration fairly and adequately compares various objective details of the films. Figure 1 (Attachment C) also properly shows ample data comparison for the reader. The chart contains multiple legends and explanations necessary for this type of chart. Without the graphic assistance the average reader would not be able to comprehend the chart and, therefore, miss the purpose. Figure 2 (Attachment D)includes data comparison as well as the other three but with less data to compare. Illustrations A, B, and C completed a higher task of data comparison because of the excessive amount of information given in each. Note: The writer could have helped the reader by putting information about the intended purpose of each table and chart. What did the writer or the preparer intend?Figures Boast Causality
All four figures allow a reader to easily learn about the presented evidence. Table 1 (Attachment A)provides clear column headings to complement the data given within the table. This method further improves the chance a reader will have of understanding the point of the table. This explanation allows the reader to learn about the evidence uncovered during the research and testing of the subjects. The setup of Table 2 (Attachment B)creates a similar effect. Attachment C allows the reader to understand the daily weather. This allowance is made possible by the previously mentioned legend. The legend enhances the reader's understanding of the illustration. The reading of Figure 1 (Attachment C) is quite simple. This simplicity of the chart allows the reader an opportunity to easily learn the presented evidence. Dr. G. Jay Christensen Page 2 Current DateMultiple Variables Require Appearance
A seemingly infinite number of variables exist in Table 1 (Attachment A). The headings for each column allow a wide array of data responses as entered data. The use of multiple variables in this chart guarantees a complete explanation of the subject. Attachment B also addresses a number of important variables. Each of the included variables builds on the next. This system of variables helps the reader understand the flow and significance of the variables on one another. Many variables are also included in Figure 1 (Attachment C). The data in this type of chart vary from one area to another. Each presented variable is necessary to construct a complete chart. Each of the variables is accompanied by an explanation to inform the reader of the reason for the variable's presence. The simplicity of Attachment D is obtained as a direct result of the low number of variables. An excessive number of variables in this chart would only cause confusion and defeat the purpose. Only a few variables are necessary to understand the few items that need to be examined in this bar chart. Note: As I read over the previous paragraph, I am left with questions. Why is there so much that the visual preparer had to include as variables? Did you notice the sentences became a little long with so many prepositions?Understanding Demands Integration
The flow of the variables in Attachment A results in beautiful integration. The data from one area relate directly to the data in the next. The structure of Table 2 (Attachment B) immediately forms an understanding of the topic in the reader's head. Each column of data relates to the next column to the right. This pattern stays consistent within the entire table. Attachment C is flawlessly drawn. The reader can credit understanding of this chart to the creator's integration of words, images, and explanations. Various colors are used to assist in conveying the information to the reader. Figure 2 Attachment D)contains text to explain the expressed data entries. Integration of of the data is not too difficult in this case because of the minimal variables. Note: The writer has made a sincere attempt to use words that convey meaning. You can tell the person has studied the visuals. The Tufte criterion is applied, and the use of color is also mentioned. That brings up a point. Make sure your table or chart appears in its original color. Color is important in trying to convey meaning. Also, take the time to explain the charts rather than let them speak for themselves.Documentation Provides Support
Table 1 (Attachment A)is supported with extensive text and research. A large amount of research was performed over the span of a few decades before the data were entered into this table. The data in Attachment B is taken from another source. This source is cited at the bottom of the table. To form a table such as this one, the original source must already have a system in place to gather the extensive amount of data. Data were retrieved from thousands of significant sources to present the data in this table. The validity of the data given in Figure 1 (Attachment C)depends on the technology used to gather it. The more advanced the weather tracking device, the more accurate the data. The exact sources for the construction of the data in Attachment D are given. Mathematical calculations are used to obtain the data in this type of chart. Some variables within the calculations are estimated or assumed. As a result, the information provided is only as accurate as the assumptions used to obtain it. Dr. G. Jay Christensen Page 3 Current DateChartjunk Decreases Value
One column appearing in Table 1 (Attachment A) provides a unique, but trivial facts. These facts disrupt the flow of the chart more than they contribute. The vague relevance of the added facts may cause a reader to lose focus of the table's main points. The breakdown of data in Table 2 (Attachment B) ensures the reader will only read quality, relevant information. Unnecessary information are not given to obstruct the view of the table's reader. Impor- tant and relevant data are all that are provided in this table. Though only a small portion of the data may be relevant to reader of Figure 1 (Attachment C), it must all be provided to cover the majority of the possible readers. Again, the quality of the data depends on the quality of the research tools used to gather the data. Figure 2 (Attachment D) uses assumptions to figure the data entered. The integrity and quality of the data depend on the accuracy of these assumptions. The creator of this chart could easily sway the numbers one way or the other by manipulating the original assumptions. Note: As I originally commented on the paper, "Much better analysis." The writer is starting to go on a tangent, however, with the discussions about assumptions and accuracy. One has to be careful in this kind of the table "not to ramble." Say what you have to say, and stop.Information Stacking Breeds Confusion
Tables 1 and 2 (Attachments A and B)insert data into distinct boxes, all of which are the same size. The uniformity of the tables increases the ease of reading them. Figure 1 (Attachment C)mixes much of the data together. This mixing of the data creates difficulty in the reader's understanding. To interpret the data given within this chart, a reader would need much more time to separate the data and anlyze what exactly is going on. The data provided in Figure 2(Attachment D) is shown adjacent in space. This setup permits easier comprehension by the reader.Number Size Plays Important Part
Qualitative Table 1 (Attachment A)does not provide any information in numerical form. Table 2 (Attachment B), on the other side, was forced to deal with large numbers. To break the numbers down for ease of comparison, the table expresses large aounts in smaller figures. This breakdown is communicated to the reader at the top of the column. "Millions" is stated in parentheses. This labeling is a common method used to solve the problem of large multiples. The numbers contained within Figure 1 (Attachment C)are broken into a scale. The scale had to be wide enough to cover the entire temperature spectrum, and in intervals small enough to render the chart useful. The numerical multiples used in Figure 2 (Attachment D)work sufficiently well for the purpose of illus- tration. Precise detail is not necessary for this graph to be successful in its intentions. Dr. G. Jay Christensen Page 4 Current DateTables and Charts Need Examining
Many details of a chart or table must be examined before one can accept the contents as valid. Specific layouts may intentionally or non-intentionally confuse a reader. The maker of a table may use certain setups to purposefully lead the reader to interpret the chart in a specific way. Written the wrong way, an illustration may sway a reader in the wrong direction for the creator. All of these details must be considered before one should believe the contents of any table or chart. Attachments: A. Table 1, ". . . ." B. Table 2, ". . . . " C. Figure 1, ". . . ." D. Figure 2, ". . . . ." Own Criteria Questions for Tables Own Criteria Questions for Charts Note: Did you spot the writer needed a way to end the memo? The writer chose to comment on the importance of visuals and their place of interpretation. The writer drew from class lectures and readings how important tables and charts have become. You must have some kind of summary paragraph.
Last updated Thursday, August 31, 2006.
(c)G. Jay Christensen, All Rights Reserved
Please check the home page for additional help, including the memo analytical report, principles of memos, talking captions, and presentations.