There is no standard that defines which chart you should choose to visualize your data. However, there are some guidelines that can help you. Here are some of them:
- As mentioned with each of the preceding charts that we have seen, it is important to understand what type of data you have. If you have continuous variables, then a histogram would be a good choice. Similarly, if you want to show ranking, an ordered bar chart would be a good choice.
- Choose the chart that effectively conveys the right and relevant meaning of the data without actually distorting the facts.
- Simplicity is best. It is considered better to draw a simple chart that is comprehensible than to draw sophisticated ones that require several reports and texts in order to understand them.
- Choose a diagram that does not overload the audience with information. Our purpose should be to illustrate abstract information in a clear way.
Having said that, let's see if we can generalize some categories of charts based on various purposes.
The following table shows the different types of charts based on the purposes:
|
Purpose |
Charts |
|
Show correlation |
Scatter plot Correlogram Pairwise plot Jittering with strip plot Counts plot Marginal histogram Scatter plot with a line of best fit Bubble plot with circling |
|
Show deviation |
Area chart Diverging bars Diverging texts Diverging dot plot Diverging lollipop plot with markers |
|
Show distribution |
Histogram for continuous variable Histogram for categorical variable Density plot Categorical plots Density curves with histogram Population pyramid Violin plot Joy plot Distributed dot plot Box plot |
|
Show composition |
Waffle chart Pie chart Treemap Bar chart |
|
Show change |
Time series plot Time series with peaks and troughs annotated Autocorrelation plot Cross-correlation plot Multiple time series Plotting with different scales using the secondary y axis Stacked area chart Seasonal plot Calendar heat map Area chart unstacked |
|
Show groups |
Dendrogram Cluster plot Andrews curve Parallel coordinates |
|
Show ranking |
Ordered bar chart Lollipop chart Dot plot Slope plot Dumbbell plot |
Note that going through each and every type of plot mentioned in the table is beyond the scope of this book. However, we have tried to cover most of them in this chapter. A few of them will be used in the upcoming chapters; we will use these graphs in more contextual ways and with advanced settings.