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Words 924

Pages 4

Team A: Roderick Hayes II, Melissa Krol, Ann Leal, Wanda Otey, and Corinn Sanders

QNT/273

May 9, 2011

Terry Dunning

Misleading Graphs Paper and Presentation

Graphs are used to give a visual image of data so readers can analyze and translate it quicker and easier than looking at a mass of numbers. However, incorrectly drawn or disproportionately drawn graphs can lead a reader to incorrect translation of data (Bluman, 2009). This document will describe the problems associated with the graph shown below, explain how they affect readers, and what needs to be done to correct the graph (University of Phoenix, 2010).

[pic]

(Misleading Graphs, 2011)

Problems

This bar chart represents sales from the year 1995 -1998, this is an assumption because there is no indication that the figures on the horizontal axis represent years. Charts can be quite useful in explaining many capacities of numbers. In looking at this chart, the boxes seem large because of the 3-D effect, which in this chart makes the 1995 bar seem taller than any of the other bars. The label “number of singles sold” on the vertical axis is unclear. The vertical axis also has no percentages or other numeric values indicating how much was sold and the horizontal axis is vague as it does not indicate what the numbers listed represent (Misleading Graphs, 2011).

Effect on Users The chart is not properly set up for users to accurately read the number of sales for each year because there are no figures on the y axis (vertical line) and the title needs to be clear as to what is being sold. This can cause a significant problem for anyone needing to know that information, by looking at this illustration a reader may get the impression that sales in 1995 were significantly higher than any other year because no sales figures are presented. The reader may also not know what is being sold because the title “number of singles sold” can represent anything from cheese slices to CDs. Another concern with the attached diagram is the 3-D effect it appears to have. With the 3-D graph the bars appear broader, larger, or higher than others, which in the above graph gives the impression that sales in 1995 were larger or higher than in 1997. If the graph were presented in another format the bars would actually appear equal. The x axis (horizontal line) should state what the figures shown represent, which in this graph is years otherwise the reader will make assumptions about what the information listed represents (Misleading Graphs, 2011). Illustrations such as the one presented here are used in decision making. For instance, an investor may use the chart above to decide if they want to invest with the company that prepared the graph. Because the graph has so many problems this investor may choose to give their hard-earned money to this company in hopes of future gains. This is why it is important to remember that when arranging a 3-D chart or any illustration, to look at how the chart will be perceived by the reader. Sometimes a simple chart is an understandable chart.

Corrections With this graph there are several items that need to be addressed to make this graph understandable. This graph needs an X and Y axis to measure the data involved. The Y axis needs to have amounts that will help show how many singles were sold. The X axis represents the years involved and it needs to clearly label that the numbers shown represent years. With the 3-D graph it is a little harder to understand the amounts because of the 3-D design. A bar graph, a pie chart, or even a linear graph would be a better view for the user. Also the source of the data needs to be referenced for the numbers of the singles sold. Below is a representation of the above graph in a standard bar format that does not mislead or misrepresent information (Misleading Graphs, 2011). Looking at the graph below one can clearly tell how many singles were sold for each year.

[pic]

(Misleading Graphs, 2011)

Conclusion

Graphs and diagrams are useful tools when someone needs to display data in a manner that is compressed and easy to understand. Although this fact is true, one must ensure the clarity and understanding of the diagram remains intact. It is easy to mislead or misinform a spectator if this does not happen. The designer and the reader of the diagrams must pay close attention to the diagram they are viewing or designing. They must be sure to verify the labels on all sides as well as within the diagram. They must first check for clarity of understanding between the key of the diagram and the diagram itself. They must make sure the diagram makes sense overall. Finally, they must ensure that the statistical data being used is represented properly in the diagram being used. These are just some of the things one must deal with when analyzing or designing a diagram or graph.

References

Bluman, A. G. (2009). Elementary Statistics: A Step by Step Approach (7th ed.). New York, NY: McGraw-Hill.

Misleading Graphs. (2011). Retrieved May 2, 2011, from BBC: http://www.bbc.co.uk/schools/gcsebitesize/maths/data/representingdata2rev5.shtml

University of Phoenix. (2010). Course Syllabus School of Business QNT/273 Version 3 Introduction to Business Statistics. Retrieved from University of Phoenix: University of Phoenix, QNT/273, Introduction to Business Statistics

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