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Displaying qualitative data - There are some important principles to consider so as to avoid misleading displays of qualitative data. The area principle must be followed. It states that the AREA of the visual should match the value it represents. You don't want to mislead the eye of the reader. When using Pie Charts it can not contain overlaps of data among the categories. Also, don't overstate results and dvaluate variables independently.

Qualitative and quantitative are displayed differently. Qualitative data is best represented by charts such as bar charts, segmented bar charts, and pie charts. Bar charts can be vertical or horizontal. There is space between the bars which represent data placed in "piles". Relative bar charts tend to be more dramatic in display. A segmented bar chart has percents of the data stacked in each bar of the chart. A pie chart displays parts of a whole. It is not the better display for comparison as a bar chart would be a better choice. Quantitative data is best represented using stem and leaf or histograms. A histogram has no space between the data displays.

Displaying Quantitative Data A histogram gives a picture of the data placed in bins. It will show a center and a spread. If a value falls on the line between bins, it will be put in the higher bin (for example; 5 - 7 bin and 7 - 9 bin a 7 will be put in the 7 - 9 bin). Before you generate a histogram try to imagine what it will look like and see if it resembles what you expected. There are no gaps between the bins (bar graphs have gaps) in this way bins with no data will be clear gaps on the histogram. You can make a histogram relative (%) and it won't change the appearance, it just changes the Y-axis values. There is a second type of histogram; the stem and leaf. Here individual datum are displayed. The stem is the first datum of each value, the leaf is the subsequent data.